Caenogastropoda is a highly diverse group,containing~60%of all existing gastropods.Species in this subclass predominantly inhabit marine environments and have a high ecological and economic value.Owing to the increase...Caenogastropoda is a highly diverse group,containing~60%of all existing gastropods.Species in this subclass predominantly inhabit marine environments and have a high ecological and economic value.Owing to the increase in relevant phylogenetic studies,our understanding of between species relatedness in Caenogastropoda has improved.However,the biodiversity,taxonomic status,and phylogenetic relationships of this group remain unclear.In the present study,we performed next-generation sequencing of four complete mitochondrial genomes from three families(Buccinidae,Columbellidae,and Cypraeidae)and the four mitogenomes were classical circular structures,with a length of 16177 bp in Volutharpa ampullacea,16244 bp in Mitrella albuginosa,16926bp in Mauritia arabica asiatica and 15422 bp in Erronea errones.Base composition analysis indicated that whole sequences were biased toward A and T.Then compared them with 171 complete mitochondrial genomes of Caenogastropoda.The phylogenetic relationship of Caenogastropoda derived from Maximum Likelihood(ML)and Bayesian Inference(BI)trees constructed based on CDS sequences was consistent with the results of traditional morphological analysis,with all three families showing close relationships.This study supported Caenogastropoda at the molecular level as a separate clade of Mollusca.According to our divergence time estimations,Caenogastropoda was formed during the middle Triassic period(~247.2–237 Ma).Our novel mitochondrial genomes provide evidence for the speciation of Caenogastropoda in addition to elucidating the mitochondrial genomic evolution of this subclass.展开更多
To identify and analyze the Orf virus in Shanxi Province, China, an Orf virus strain was successfully isolated from crust materials of boer goat with clinical sore mouth symptom from a goat farm of Shanxi Province by ...To identify and analyze the Orf virus in Shanxi Province, China, an Orf virus strain was successfully isolated from crust materials of boer goat with clinical sore mouth symptom from a goat farm of Shanxi Province by passaging in lamb testis (LT). The Orf virus was identified by enzyme linked immunosorbent assay (ELISA) test, recurrent infection test, transmission electron microscopy, and PCR. The nucleotide and amino acid sequences of two genes of the Orf virus were analyzed. The results showed that under the electron microscopy the virus had a presence of typical parapoxvirus virions and there were many eosinophilic intracytoplasmic inclusions observed by hematoxylin-eosin (H&E) stain. In ELISA test, optical density (OD) readings of the sample showed a positive result, and the rabbits infected with the virus showed a typically Orf virus-infected appearance. All these findings proved that the sample was an Orf virus. The phylogenetic studies of Orf B2L and Orf F1L genes showed that the virus clustered in different branches and were closer to the Orf virus Nantou (DQ904351) and the OV-SA00 isolates (AY386264). Furthermore, the above results may provide some insight into the genotype of the etiological agent responsible for the Orf outbreak in Shanxi Province, and could also provide a comparative view of the B2L and F1L genes of parapoxvirus.展开更多
Bacterium strain EVA17 was isolated from an oil-contaminated soil, and identified as Sphingomonas sp. based on analysis of 16S rDNA sequence,cellular fatty acid composition and physiological-chemical tests. The salicy...Bacterium strain EVA17 was isolated from an oil-contaminated soil, and identified as Sphingomonas sp. based on analysis of 16S rDNA sequence,cellular fatty acid composition and physiological-chemical tests. The salicylate hydroxylase and catechol 2,3-dioxygenase(C23O) were detected in cell-free lysates, suggesting a pathway for phenanthrene catabolism via salicylate and catechol. Alignment showed that both of the C23O and GST genes of the strain EVA17 had high similarity with homologues of strains from genus Sphingomonas. The phylogenetic analysis based on 16S rDNA and C23O gene sequence indicated that EVA17 should be classified into genus Sphingomonas, although the two phylogenetic trees were slightly different from each other. The results of co-amplification and sequence determination indicated that GST gene should be located upstream of the C23O gene.展开更多
Mitogen activated protein kinases (MAPK) cascades based on protein phosphorylation play an important role in plant growth and development. In this study, we have identified 15 putative members of the wheat MAPK gene...Mitogen activated protein kinases (MAPK) cascades based on protein phosphorylation play an important role in plant growth and development. In this study, we have identified 15 putative members of the wheat MAPK gene (TaMPK) family through an in silico search of wheat expressed sequence tags (EST) databases based on the presence of amino acid sequence of Arabidopsis and rice MAPKs. Phylogenetic analyses of MAPKs from wheat, rice and Arabidopsis genomes have classified them into seven subgroups (A, B, C, D, E, F, and G). Using the available EST information as a source of expression data, the MAPK family genes from Triticum aestivum were detected in diverse tissues. Further expression analysis of the MAPKs in NCBI EST database revealed that their transcripts were most abundant in callus (20%), followed by leaf (12%) and inflorescence (12%). Most MAPK family genes showed some tissue specificity.展开更多
H9N2 avian influenza virus(AIV) infection is a major problem in poultry industry worldwide. In this study, molecular characterizations and phylogenetic relationships of hemagglutinin(HA) gene sequences of H9N2 AIV...H9N2 avian influenza virus(AIV) infection is a major problem in poultry industry worldwide. In this study, molecular characterizations and phylogenetic relationships of hemagglutinin(HA) gene sequences of H9N2 AIV of 5 Chinese isolates in 2014 recently available in Gen Bank, 3 widely used vaccine strains, and 52 novel isolates in China from 2013 to 2015 were analyzed. The homology analysis showed that the nucleotide sequences of HA gene of these recent Chinese H9N2 AIV isolates shared homologies from 94.1 to 99.9%. Phylogenetic analysis showed that all isolates belonged to AIV lineage h9.4.2.5. Fifty-six out of the 57 recent Chinese H9N2 AIV isolates had the motifs PSRSSR↓GLF at the cleavage sites within the HA protein, while one isolate PWH01 harbored LSRSSR↓GLF. Remarkably, all of the recent Chinese H9N2 AIV strains had the Q216 L substitution in the receptor binding site, which indicated that they had potential to infect humans. Most of recent Chinese H9N2 AIV isolates lost the potential N-linked glycosylation site at residues 200–202 compared with vaccine strains. This present study demonstrated that AIV lineage h9.4.2.5 was more predominant in China than other lineages as it harbored all the H9N2 AIV isolated between 2013 and 2015. Also we showed the importance of continuous surveillance of emerging H9N2 AIV in China and update of vaccine formulation accordingly in order to prevent and control H9N2 AIV.展开更多
This study presents the complete mitochondrial genome of the hybrid Epinephelus moara♀× Epinephelus lanceolatus♂. The genome is 16886 bp in length, and contains 13 protein-coding genes, 2 r RNA genes, 22 t RNA ...This study presents the complete mitochondrial genome of the hybrid Epinephelus moara♀× Epinephelus lanceolatus♂. The genome is 16886 bp in length, and contains 13 protein-coding genes, 2 r RNA genes, 22 t RNA genes, a light-strand replication origin and a control region. Additionally, phylogenetic analysis based on the nucleotide sequences of 13 conserved protein-coding genes using the maximum likelihood method indicated that the mitochondrial genome is maternally inherited. This study presents genomic data for studying phylogenetic relationships and breeding of hybrid Epinephelinae.展开更多
Microbial reduction of As(V)(i.e.,arsenate)plays an important role in arsenic(As)mobilization in aqueous environment.In this study,we investigated As(V)reduction characteristics of the bacteria enriched from the arsen...Microbial reduction of As(V)(i.e.,arsenate)plays an important role in arsenic(As)mobilization in aqueous environment.In this study,we investigated As(V)reduction characteristics of the bacteria enriched from the arsenic-contaminated soil at an abandoned smelter site.It was found that As(V)was completely reduced to As(III)(i.e.,arsenite)in 21 h.After 3-d incubation,a yellow solid was precipitated and the concentration of As(III)decreased sharply.After 150 h incubation,ca.65%of soluble arsenic was removed fro...展开更多
The genetic variation and phylogenetic relationships of Citrus tristeza virus (CTV) isolates collected from Chinese wild type citrus were analyzed by comparing the sequences of nine genomic regions (p23, p20, p13, ...The genetic variation and phylogenetic relationships of Citrus tristeza virus (CTV) isolates collected from Chinese wild type citrus were analyzed by comparing the sequences of nine genomic regions (p23, p20, p13, p18, p25, p27, POL, HEL and k17) with the CTV isolates of cultivated citrus from different countries. The results showed that the divergence pattern of genomic RNA of the CTV isolates from wild type citrus was similar to that of other isolates from cultivated citrus, the 3′ proximal region was relatively conserved, and the 5′ proximal region had greater variability. The nine genomic regions of CTV isolates analyzed were found to have been under purifying selection in the evolution process. Phylogenetic analysis showed that the eleven Chinese wild CTV isolates were located at different clades and did not relfect their geographical origins, suggesting genetic diversity among the Chinese wild CTV populations. These results will aid in the understanding of molecular evolution of the Chinese CTV populations.展开更多
Metabolites derived from marine symbiotic microorganisms have great potential as lead compounds for the discovery of novel marine drugs. Euphausia superba Dana, which lives in the Antarctic Ocean, is regarded as a new...Metabolites derived from marine symbiotic microorganisms have great potential as lead compounds for the discovery of novel marine drugs. Euphausia superba Dana, which lives in the Antarctic Ocean, is regarded as a new source of marine microbial natural products. However, no studies have examined the biodiversity of the symbiotic intestinal microbiome of E. superba. To address this issue, the species diversity and abundance of the gut microbiome of E. superba Dana from the Rose Sea of the Antarctic Ocean were analyzed by culture-independent high-throughput sequencing and pure culture methods. A comparison with gene databases revealed that the microbiome contained 61 known microbial species and a plethora of uncultivable microorganisms. Additionally, 7% of the species in the microbiome were currently unknown. The microbes belonged to 56 genera, eight of which, including Arthrobacter, Bacillus, Candidatus, Lactococcus, Lysinibacillus, Leuconostoc, Solibacillus, and Vibrio, were dominant, as were Vibrionaceae spp. Moreover, 81 microbial strains were isolated by the pure culture method, and they belonged to 36 genera, including Mobilicoccus, Rhodococcus, Arthrobacter, and Microbacterium. The results obtained by two different methods demonstrate the richness of the microbial biodiversity of the gut microbiome of E. superba, and it also suggests that they have good potential for the discovery of novel marine microbial species.展开更多
[ Objective] This study aimed to isolate and identify Vibrio ichthyoenteri strains from diseased Hapalogenys nitens. [ Method] In January 2013, dis- eased H. nitens juveniles from a maricultural farm in Luoyuanwan Bay...[ Objective] This study aimed to isolate and identify Vibrio ichthyoenteri strains from diseased Hapalogenys nitens. [ Method] In January 2013, dis- eased H. nitens juveniles from a maricultural farm in Luoyuanwan Bay of Fuzhou City were selected to investigate the incidence, clinical symptoms and pathogenic characteristics. Liver, spleen, kidney and gill of five diseased H. nitens juveniles were collected for bacterial isolation and pure culture to conduct morphological, physiological and biochemical assays, 16S rRNA gene sequencing and phylogenetic analysis. The susceptibility of five strains to 30 kinds of antimicrobial drugs was detected. [ Result] The death of H. nitens juveniles was caused by bacterial infections. The isolated strains fzlyw201301071 and fzlyw201301072 belonged to the same genus as Vibrio ichthyoenteri. Drug susceptibihty test suggested that there were no significant differences in drug sensitivity and resistance among different strains. [ Conclusion] This study provided theoretical basis for the prevention and control of diseases in aquaculture animals.展开更多
Hydro-Pericardium Hepatitis (HPH) is an emerging infectious disease of commercial poultry, caused by different serotypes of Fowl Adeno Virus. The vertical transmission of the virus into the progeny may results in deva...Hydro-Pericardium Hepatitis (HPH) is an emerging infectious disease of commercial poultry, caused by different serotypes of Fowl Adeno Virus. The vertical transmission of the virus into the progeny may results in devastating damage, causing huge economic losses to its farmers. In present study, molecular typing is performed on basis of partially conserved hexon gene sequences, using a unique set of primers having common reverse oligo for simultaneous detection of FAdV1, FAdV-4 and FAdV-11. A total of 14 fowl adeno virus strains were isolated from 100 suspected adeno virus liver samples, collected from different districts in Pakistan, between 2018 and 2019. FASTA’s sequence alignment and phylogenetic analysis revealed that out of the 14, one isolate which belonged to group A showed 27% similarity with FAdV-1, while three isolates showed 99%, 95% & 45% similarity to FAdV-4 (Group C). Whereas, ten isolates showed more than 99% similarity to FAdV-11 (Group D). The serotypes FAdV1, FAdV-4 and FAdV-11 are prevailing in the breeder and broilers. These results hold great importance in rapid, reliable and simultaneous detection of the three FAdV serotypes. Therefore, fowl adeno virus vaccine production for commercial poultry shall be according to the prevalent field serotypes.展开更多
Canine coronavirus(CCoV),a member of the genus Alphocoronavirus,is an enveloped,single-stranded positive-sense RNA virus that responsible for gastroenteritis in dogs.In this study,two CCoV isolates were successfully p...Canine coronavirus(CCoV),a member of the genus Alphocoronavirus,is an enveloped,single-stranded positive-sense RNA virus that responsible for gastroenteritis in dogs.In this study,two CCoV isolates were successfully propagated from 53 CCoV-positive clinical specimens by serial passaging in A-72 cells.These two strains,CCoV JS1706 and CCoV JS1712,caused cytopathic effects in A-72 cells.The sizes of virus plaque formed by them differed in early passages.Electron microscopy revealed a large quantity of typical coronavirus particles with 80-120 nm in diameter in cell culture media and cytoplasm of infected cells,in which they appeared as inclusion bodies.RT-PCR analysis of 5 gene indicated that these two isolates were belonged to CCoV lla subtype.Homology of RdRp,S,M and N proteins between the two strains were 100,99.6,99.2 and 100.0%,respectively,whereas they were 99.4-100%,83.1-95.2%,88.5-99.2% and 91.9-99.7%identity compared to CCoV II reference strains.Phylogenetic analysis of RdRp,S,M and N protein showed that they were closely related to CCoV II strains.These two subtype lla isolates will be useful for evaluating the pathogenesis and evolution of CCoV and for developing diagnostic reagents and vaccines.展开更多
The diversity of sulfate-reducing bacteria (SRB) from deep layers of deep-sea sediments [ more than 2 m bsf (below seafloor) ] of two sites (WO1 -3 and WPO1 -4) in a tropical West Pacific warm pool region was ch...The diversity of sulfate-reducing bacteria (SRB) from deep layers of deep-sea sediments [ more than 2 m bsf (below seafloor) ] of two sites (WO1 -3 and WPO1 -4) in a tropical West Pacific warm pool region was characterized by using molecular phylogenetic analysis. The results of culture-independent samples demonstrated that the dominant clones from both sites were related to Grampositive spore forming genus, Desulfotomaculum, which accounted for 36.8% of all the sequencing clones from Site WP01 - 3 and 62.8% from Site WP01 -4. However, the other SRB group which was generally reported to be predominant in the deep-sea sediments of other regions, δ- subclass of the proteobacteria was found to be in very low percentages. Therefore, it could be speculated that there existed a unique chemical environment in the deep-sea sediment of this warm pool region. When comparing the Desulfotomaculum sp. related sequences from both sites, it was revealed that though the Desulfotomaculum-like sequences from Site WP01 -3 were more diverse than those from Site WP01 -4, all these sequences from both sites showed high similarity and formed a new phylogenetically homogeneous cluster in the Desulfotomaculum genus which had never been reported before. Successful enrichment of SRB was only achieved from samples of Site WP01 -4 and the sequence analysis of culture-dependent samples further confirmed the dominance of Desulfotomaculum genus. But Desulfotomaculum-related sequences from culture-dependent and culture-independent samples belonged to two different clusters respectively. This difference showed the choice of cultivation to the microorganisms.展开更多
A study of the genetic structure of an ancient human excavated from the Yikeshu site of Yuanshangdu ancient city in Inner Mongolia and the relationships between the ancient population and the extant populations was ca...A study of the genetic structure of an ancient human excavated from the Yikeshu site of Yuanshangdu ancient city in Inner Mongolia and the relationships between the ancient population and the extant populations was carried out. Sequences of the control region and coding region of mtDNA from the ancient human were analyzed by using direct sequencing and restriction-fragment length polymorphism (RFLP) methods, Phylogenetic analysis and multidimensional scaling analysis were also performed on the mtDNA data of the ancient population and 12 extant populations. These results show that the ancient individuals of Yikeshu site can be assigned to D, G, B and Z haplogroups that are prevalent in Duars and Mongolians from Inner Mongolia. The ancient population is also closer to Duar and Mongolian populations in genetic distance than other compared populations. This study reveals that the ancient population from Yikeshu site in the Yuan Dynasty shares a common ancestor with Mongolic-speaking Daur and Mongolian tribes.展开更多
Porcine epidemic diarrhea(PED)is caused by porcine epidemic diarrhea virus(PEDV),and is characterized by vomiting,diarrhea and dehydration of suckling pigs from 80% to 100% morbidity and 50% to 90% mortality,and resul...Porcine epidemic diarrhea(PED)is caused by porcine epidemic diarrhea virus(PEDV),and is characterized by vomiting,diarrhea and dehydration of suckling pigs from 80% to 100% morbidity and 50% to 90% mortality,and resulted in tremendous economic losses to swine industry.The PEDV mainly infects small intestine of pigs,resulting in vacuolar degeneration and necrosis of mucosal epithelium.The IPEC-J2 is a pig intestine epithelial cell line,which is similar to the intestinal environment of piglets,can be used to isolate and identify the PEDV field isolates.In this study,it appeared the PEDV typical postmortem changes and histopathological lesion of degeneration and destruction of small intestine in infected piglets,and IHC identified that the PEDV distributed in the mucosa and submucosa of small intestine mostly.Furthermore,the PEDV HLJ strain was successfully isolated and characterized in the IPEC-J2 cells,and indicated that the IPEC-J2 cell line was sensitive to isolate and adapt the PEDV field strain,and could be utilized to multiply the PEDV rapidly.The S gene analysis indicated that the PEDV HLJ strain was the prevailed virus,belonged to Group 1 with attenuated virulent DR13,SC1402 and J-S2/2015 strains isolated in South Korea and China from 2014 to 2015.This study had important theoretical and practical significances on analyzing genetic variation of the PEDV,understanding the pathogenic characteristics of the virus and developing new vaccines for the PED.展开更多
Encephalomyocarditis virus(EMCV)is a positive single-stranded small RNA virus without envelope,which can infect a variety of mammals.Swines are the most susceptible animals,which can cause acute myocarditis and respir...Encephalomyocarditis virus(EMCV)is a positive single-stranded small RNA virus without envelope,which can infect a variety of mammals.Swines are the most susceptible animals,which can cause acute myocarditis and respiratory failure in piglets and reproductive failure in pregnant sows.Diseases caused by EMCV have a wide range of effects on the global swine industry.In this study,a strain of EMCV was isolated from a swine aborted fetus in northeast China.It was identified by reverse transcriptase polymerase chain reaction(RT-PCR),electron microscopic observation and indirect immunofluorescence assay.The subsequent results showed that the virus titer of HLJ strain grew to 8.3 lgTCID50 on baby hamster kidney 21(BHK-21)cells.And HLJ strain caused the specific cytopathic effect(CPE)on BHK-21 cells and severe pathological changes in mice.Complete genome sequencing and multiple sequence alignment showed that the homology between HLJ strain and other isolates worldwide was 71.5%-99.7%.Phylogenetic analysis showed that EMCV isolates fell into five clusters:lineageⅠ,Ⅱ,Ⅲ,ⅣandⅤ,based on the nucleotide sequences of the entire open reading frame(ORF)and VP1 gene.HLJ isolate was grouped into lineage I.The analyses of amino acid mutation sites of VP1 protein showed that the amino acids at positions 20 and 54 in VP1 junction were unique to HLJ strain.The isolation of HLJ strain enriched the epidemiological database of EMCV.展开更多
Feline calicivirus(FCV)is an important feline pathogen mainly causing upper respiratory tract disease,conjunctivitis,and stomatitis,and it is classifed into genotype I and genotype II.To investigate the prevalence and...Feline calicivirus(FCV)is an important feline pathogen mainly causing upper respiratory tract disease,conjunctivitis,and stomatitis,and it is classifed into genotype I and genotype II.To investigate the prevalence and molecular characteristics of FCV,this study collected 337 cat swab samples from animal hospitals in diferent regions of China from 2019 to 2021.The positive detection rate of FCV was 29.9%(101/337)by RT-PCR.Statistical analysis showed that FCV prevalence was signifcantly associated with living environment(p=0.0004),age(p=0.031)and clinical symptoms(p=0.00),but not with sex(p=0.092)and breed(p=0.171).The 26 strains of FCV were isolated using F81 cells.Phylogenetic analysis showed that 10 isolates belonged to genotype I,and 16 isolates belonged to genotype II.These 26 isolates were highly genetically diverse,of which HB7 isolate had three same virulence-related amino acid loci with VSD strains.Potential loci distinguishing diferent genotypes were identifed from 26 isolates,suggesting the genetic relationship between diferent genotypes.In addition,selection pressure analysis based on capsid protein of 26 isolates revealed that the protein is under diversifying selection.This study reveals the genetic diversity of FCV and provides a reference for the screening of vaccine candidate strains and the development of vaccines with better cross-protection efects.展开更多
[Objectives]This study was conducted to determine the pathogen species and dominant species of sugarcane pokkah boeng in the sugarcane areas of Yunnan in the low-latitude plateau,so as to provide a basis for the patho...[Objectives]This study was conducted to determine the pathogen species and dominant species of sugarcane pokkah boeng in the sugarcane areas of Yunnan in the low-latitude plateau,so as to provide a basis for the pathogenic mechanism,disease resistance breeding and scientific prevention and control of pokkah boeng.[Methods]With 14 pokkah boeng samples collected from different sugarcane areas in Yunnan as materials,pokkah boeng-specific detection primers FvF4/Fv-R4 and Fp-F3/Fp-R3 were designed based on ribosomal DNA non-transcribed spacer(rDNA-ITS)sequences,respectively,and used to perform PCR on Fusarium verticillioides and F.proliferatum.[Results]In 12 of the 14 pokkah boeng samples,two species of pokkah boeng pathogens were detected,and there was a phenomenon of composite infection.Seven composite infection samples were selected for sequence alignment and phylogenetic analysis.The sequences of F.verticillioides(Gen Bank accession number:MZ126549-MZ126555)and F.proliferatum(Gen Bank accession number:MZ102259-MZ102265)from seven composite infection samples shared 98.6%-100%and 100%with F.verticillioides strain 20(Gen Bank accession number:KU508286)and F.proliferatum Dehong strain(GenBank accession number:KJ629482)published in Gen Bank,respectively.The phylogenetic tree showed that the pathogens of sugarcane pokkah boeng in Yunnan were mainly divided into the F.verticillioides group and F.proliferatum group.In the F.verticillioides group,except for ROC 25(Lancang,Yunnan)and Funong10-1405(Maitreya,Yunnan)which were on an independent branch,the remaining five composite infection samples were grouped with F.verticillioides strains from different geographical origins,and were closely related to F.oxysporum Guangxi strain.All strains of F.proliferatum from different geographic origins were clustered into another group.[Conclusions]This study provides a scientific basis for disease resistance breeding and disease prevention and control of sugarcane pokkah boeng.展开更多
[Objective] The paper was to provide a basis for scientific prevention and control of pigeon Newcastle disease(ND).[Method] The HN gene of eight pigeon NDV strains isolated from different pigeon farms in Guangxi wer...[Objective] The paper was to provide a basis for scientific prevention and control of pigeon Newcastle disease(ND).[Method] The HN gene of eight pigeon NDV strains isolated from different pigeon farms in Guangxi were amplified by RT-PCR,sequenced and analyzed.The molecular evolution characteristics of HN gene of pigeon NDV isolates in Guangxi was discussed.[Result] The nucleotide sequence length of HN gene of the eight NDV isolates was 1 716 bp,encoding 571 amino acids.They belonged to virulent group C,and the gene length characteristic of HN gene accorded with virulent strain.Analysis of nucleotide homologies indicated that the eight NDV isolates shared higher homology with genotype VIb,ranging from 90.4% to 99.5%.Phylogenetic tree analysis demonstrated that the genetic relationship between the eight NDV strains in Gangxi and the NDV isolates from Guangxi,Guangdong,Jilin,Liaoning,Yunnan and Heilongjiang during 2011 and 2013 was close.They were located in the same cladogram branch.[Conclusion] We assume that the eight pigeon NDV isolates in Guangxi all belong to the gene class II genotype VI b NDV.展开更多
Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole perce...Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G+C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter.展开更多
基金Research and Development Program of Shandong Province,China(Major Science and Technology Innovation Project)under contract No.2021CXGC011306MNR Key Laboratory of Eco-Environmental Science and Technology,China under contract No.MEEST-2021-05+2 种基金Natural Science Foundation of Shandong Province under contract No.ZR2020MD002Doctoral Science Research Foundation of Yantai University under contract Nos SM15B01,SM19B70 and SM19B28Double-Hundred Action of Yantai City under contract No.2320004-SM20RC02。
文摘Caenogastropoda is a highly diverse group,containing~60%of all existing gastropods.Species in this subclass predominantly inhabit marine environments and have a high ecological and economic value.Owing to the increase in relevant phylogenetic studies,our understanding of between species relatedness in Caenogastropoda has improved.However,the biodiversity,taxonomic status,and phylogenetic relationships of this group remain unclear.In the present study,we performed next-generation sequencing of four complete mitochondrial genomes from three families(Buccinidae,Columbellidae,and Cypraeidae)and the four mitogenomes were classical circular structures,with a length of 16177 bp in Volutharpa ampullacea,16244 bp in Mitrella albuginosa,16926bp in Mauritia arabica asiatica and 15422 bp in Erronea errones.Base composition analysis indicated that whole sequences were biased toward A and T.Then compared them with 171 complete mitochondrial genomes of Caenogastropoda.The phylogenetic relationship of Caenogastropoda derived from Maximum Likelihood(ML)and Bayesian Inference(BI)trees constructed based on CDS sequences was consistent with the results of traditional morphological analysis,with all three families showing close relationships.This study supported Caenogastropoda at the molecular level as a separate clade of Mollusca.According to our divergence time estimations,Caenogastropoda was formed during the middle Triassic period(~247.2–237 Ma).Our novel mitochondrial genomes provide evidence for the speciation of Caenogastropoda in addition to elucidating the mitochondrial genomic evolution of this subclass.
基金supported by the National Key Technologies R&D Program during the 11th Five-Year Plan period of China (2007BAD56B06)
文摘To identify and analyze the Orf virus in Shanxi Province, China, an Orf virus strain was successfully isolated from crust materials of boer goat with clinical sore mouth symptom from a goat farm of Shanxi Province by passaging in lamb testis (LT). The Orf virus was identified by enzyme linked immunosorbent assay (ELISA) test, recurrent infection test, transmission electron microscopy, and PCR. The nucleotide and amino acid sequences of two genes of the Orf virus were analyzed. The results showed that under the electron microscopy the virus had a presence of typical parapoxvirus virions and there were many eosinophilic intracytoplasmic inclusions observed by hematoxylin-eosin (H&E) stain. In ELISA test, optical density (OD) readings of the sample showed a positive result, and the rabbits infected with the virus showed a typically Orf virus-infected appearance. All these findings proved that the sample was an Orf virus. The phylogenetic studies of Orf B2L and Orf F1L genes showed that the virus clustered in different branches and were closer to the Orf virus Nantou (DQ904351) and the OV-SA00 isolates (AY386264). Furthermore, the above results may provide some insight into the genotype of the etiological agent responsible for the Orf outbreak in Shanxi Province, and could also provide a comparative view of the B2L and F1L genes of parapoxvirus.
文摘Bacterium strain EVA17 was isolated from an oil-contaminated soil, and identified as Sphingomonas sp. based on analysis of 16S rDNA sequence,cellular fatty acid composition and physiological-chemical tests. The salicylate hydroxylase and catechol 2,3-dioxygenase(C23O) were detected in cell-free lysates, suggesting a pathway for phenanthrene catabolism via salicylate and catechol. Alignment showed that both of the C23O and GST genes of the strain EVA17 had high similarity with homologues of strains from genus Sphingomonas. The phylogenetic analysis based on 16S rDNA and C23O gene sequence indicated that EVA17 should be classified into genus Sphingomonas, although the two phylogenetic trees were slightly different from each other. The results of co-amplification and sequence determination indicated that GST gene should be located upstream of the C23O gene.
基金supported by the Genetically Modified Organisms Breeding Major Projects, China (2008ZX08002-002, 2008ZX08002-003, 2008ZX08002-004)the Beijing Technical Nova Project, China (2007B056, 2008B035)+2 种基金the Excellence Scholar Fostered Program of Beijing Government,China (20081D0200500050)the Beijing Natural Science Foundation of China (5102016)Young Foundation Project of Beijing Academy of Agriculture and Forestry Scientific Research, China
文摘Mitogen activated protein kinases (MAPK) cascades based on protein phosphorylation play an important role in plant growth and development. In this study, we have identified 15 putative members of the wheat MAPK gene (TaMPK) family through an in silico search of wheat expressed sequence tags (EST) databases based on the presence of amino acid sequence of Arabidopsis and rice MAPKs. Phylogenetic analyses of MAPKs from wheat, rice and Arabidopsis genomes have classified them into seven subgroups (A, B, C, D, E, F, and G). Using the available EST information as a source of expression data, the MAPK family genes from Triticum aestivum were detected in diverse tissues. Further expression analysis of the MAPKs in NCBI EST database revealed that their transcripts were most abundant in callus (20%), followed by leaf (12%) and inflorescence (12%). Most MAPK family genes showed some tissue specificity.
基金supported by the National Modern Agricultural Industry Technology System Project of China(CARS-41)the Science and Technology Plan Project of Guangdong Province,China(2012B020306002 and 2012B091100078)
文摘H9N2 avian influenza virus(AIV) infection is a major problem in poultry industry worldwide. In this study, molecular characterizations and phylogenetic relationships of hemagglutinin(HA) gene sequences of H9N2 AIV of 5 Chinese isolates in 2014 recently available in Gen Bank, 3 widely used vaccine strains, and 52 novel isolates in China from 2013 to 2015 were analyzed. The homology analysis showed that the nucleotide sequences of HA gene of these recent Chinese H9N2 AIV isolates shared homologies from 94.1 to 99.9%. Phylogenetic analysis showed that all isolates belonged to AIV lineage h9.4.2.5. Fifty-six out of the 57 recent Chinese H9N2 AIV isolates had the motifs PSRSSR↓GLF at the cleavage sites within the HA protein, while one isolate PWH01 harbored LSRSSR↓GLF. Remarkably, all of the recent Chinese H9N2 AIV strains had the Q216 L substitution in the receptor binding site, which indicated that they had potential to infect humans. Most of recent Chinese H9N2 AIV isolates lost the potential N-linked glycosylation site at residues 200–202 compared with vaccine strains. This present study demonstrated that AIV lineage h9.4.2.5 was more predominant in China than other lineages as it harbored all the H9N2 AIV isolated between 2013 and 2015. Also we showed the importance of continuous surveillance of emerging H9N2 AIV in China and update of vaccine formulation accordingly in order to prevent and control H9N2 AIV.
基金supported by grants from Dahuanong Aquatic Company, Guangdong, and Taishan Scholar Project, Shandong, China
文摘This study presents the complete mitochondrial genome of the hybrid Epinephelus moara♀× Epinephelus lanceolatus♂. The genome is 16886 bp in length, and contains 13 protein-coding genes, 2 r RNA genes, 22 t RNA genes, a light-strand replication origin and a control region. Additionally, phylogenetic analysis based on the nucleotide sequences of 13 conserved protein-coding genes using the maximum likelihood method indicated that the mitochondrial genome is maternally inherited. This study presents genomic data for studying phylogenetic relationships and breeding of hybrid Epinephelinae.
基金supported by the National Natural Sci-ence Foundation of China(No.40673079,40773076).
文摘Microbial reduction of As(V)(i.e.,arsenate)plays an important role in arsenic(As)mobilization in aqueous environment.In this study,we investigated As(V)reduction characteristics of the bacteria enriched from the arsenic-contaminated soil at an abandoned smelter site.It was found that As(V)was completely reduced to As(III)(i.e.,arsenite)in 21 h.After 3-d incubation,a yellow solid was precipitated and the concentration of As(III)decreased sharply.After 150 h incubation,ca.65%of soluble arsenic was removed fro...
基金supported by the National Natural Science Foundation of China (30900977)the Program for Changjiang Scholars and Innovative Research Team in Universities, China (PCSIRT, IRT0976)+1 种基金the Key Project 210111 of Ministry of Education of Chinathe Young Scientist Cultivation Program of Jiangxi, China (2010DQ02300)
文摘The genetic variation and phylogenetic relationships of Citrus tristeza virus (CTV) isolates collected from Chinese wild type citrus were analyzed by comparing the sequences of nine genomic regions (p23, p20, p13, p18, p25, p27, POL, HEL and k17) with the CTV isolates of cultivated citrus from different countries. The results showed that the divergence pattern of genomic RNA of the CTV isolates from wild type citrus was similar to that of other isolates from cultivated citrus, the 3′ proximal region was relatively conserved, and the 5′ proximal region had greater variability. The nine genomic regions of CTV isolates analyzed were found to have been under purifying selection in the evolution process. Phylogenetic analysis showed that the eleven Chinese wild CTV isolates were located at different clades and did not relfect their geographical origins, suggesting genetic diversity among the Chinese wild CTV populations. These results will aid in the understanding of molecular evolution of the Chinese CTV populations.
基金funds from national non-profit institutes (East China Sea Fisheries Research Institute) (Grant no.2014M02)the Opening Fund Project (Grant no.KP201406) of the State Oceanic Administration Key Laboratory for Polar Science at the Polar Research Institute of China+1 种基金the Chinese Polar Environment Comprehensive Investigation & Assessment Program (Grant no.CHINARE2016-01-05)the National High-tech R&D Program of China (Program 863, Grant no.2012AA092105)
文摘Metabolites derived from marine symbiotic microorganisms have great potential as lead compounds for the discovery of novel marine drugs. Euphausia superba Dana, which lives in the Antarctic Ocean, is regarded as a new source of marine microbial natural products. However, no studies have examined the biodiversity of the symbiotic intestinal microbiome of E. superba. To address this issue, the species diversity and abundance of the gut microbiome of E. superba Dana from the Rose Sea of the Antarctic Ocean were analyzed by culture-independent high-throughput sequencing and pure culture methods. A comparison with gene databases revealed that the microbiome contained 61 known microbial species and a plethora of uncultivable microorganisms. Additionally, 7% of the species in the microbiome were currently unknown. The microbes belonged to 56 genera, eight of which, including Arthrobacter, Bacillus, Candidatus, Lactococcus, Lysinibacillus, Leuconostoc, Solibacillus, and Vibrio, were dominant, as were Vibrionaceae spp. Moreover, 81 microbial strains were isolated by the pure culture method, and they belonged to 36 genera, including Mobilicoccus, Rhodococcus, Arthrobacter, and Microbacterium. The results obtained by two different methods demonstrate the richness of the microbial biodiversity of the gut microbiome of E. superba, and it also suggests that they have good potential for the discovery of novel marine microbial species.
基金Supported by Program of Aquatic Animal Disease Monitoring in Fujian Province(2012)Program of Fishery Pest Control in Fuzhou City(2012)
文摘[ Objective] This study aimed to isolate and identify Vibrio ichthyoenteri strains from diseased Hapalogenys nitens. [ Method] In January 2013, dis- eased H. nitens juveniles from a maricultural farm in Luoyuanwan Bay of Fuzhou City were selected to investigate the incidence, clinical symptoms and pathogenic characteristics. Liver, spleen, kidney and gill of five diseased H. nitens juveniles were collected for bacterial isolation and pure culture to conduct morphological, physiological and biochemical assays, 16S rRNA gene sequencing and phylogenetic analysis. The susceptibility of five strains to 30 kinds of antimicrobial drugs was detected. [ Result] The death of H. nitens juveniles was caused by bacterial infections. The isolated strains fzlyw201301071 and fzlyw201301072 belonged to the same genus as Vibrio ichthyoenteri. Drug susceptibihty test suggested that there were no significant differences in drug sensitivity and resistance among different strains. [ Conclusion] This study provided theoretical basis for the prevention and control of diseases in aquaculture animals.
文摘Hydro-Pericardium Hepatitis (HPH) is an emerging infectious disease of commercial poultry, caused by different serotypes of Fowl Adeno Virus. The vertical transmission of the virus into the progeny may results in devastating damage, causing huge economic losses to its farmers. In present study, molecular typing is performed on basis of partially conserved hexon gene sequences, using a unique set of primers having common reverse oligo for simultaneous detection of FAdV1, FAdV-4 and FAdV-11. A total of 14 fowl adeno virus strains were isolated from 100 suspected adeno virus liver samples, collected from different districts in Pakistan, between 2018 and 2019. FASTA’s sequence alignment and phylogenetic analysis revealed that out of the 14, one isolate which belonged to group A showed 27% similarity with FAdV-1, while three isolates showed 99%, 95% & 45% similarity to FAdV-4 (Group C). Whereas, ten isolates showed more than 99% similarity to FAdV-11 (Group D). The serotypes FAdV1, FAdV-4 and FAdV-11 are prevailing in the breeder and broilers. These results hold great importance in rapid, reliable and simultaneous detection of the three FAdV serotypes. Therefore, fowl adeno virus vaccine production for commercial poultry shall be according to the prevalent field serotypes.
基金This work was supported by the Open Project Program of Jiangsu Key Laboratory of Zoonosis(No.1604,No.1804)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Canine coronavirus(CCoV),a member of the genus Alphocoronavirus,is an enveloped,single-stranded positive-sense RNA virus that responsible for gastroenteritis in dogs.In this study,two CCoV isolates were successfully propagated from 53 CCoV-positive clinical specimens by serial passaging in A-72 cells.These two strains,CCoV JS1706 and CCoV JS1712,caused cytopathic effects in A-72 cells.The sizes of virus plaque formed by them differed in early passages.Electron microscopy revealed a large quantity of typical coronavirus particles with 80-120 nm in diameter in cell culture media and cytoplasm of infected cells,in which they appeared as inclusion bodies.RT-PCR analysis of 5 gene indicated that these two isolates were belonged to CCoV lla subtype.Homology of RdRp,S,M and N proteins between the two strains were 100,99.6,99.2 and 100.0%,respectively,whereas they were 99.4-100%,83.1-95.2%,88.5-99.2% and 91.9-99.7%identity compared to CCoV II reference strains.Phylogenetic analysis of RdRp,S,M and N protein showed that they were closely related to CCoV II strains.These two subtype lla isolates will be useful for evaluating the pathogenesis and evolution of CCoV and for developing diagnostic reagents and vaccines.
文摘The diversity of sulfate-reducing bacteria (SRB) from deep layers of deep-sea sediments [ more than 2 m bsf (below seafloor) ] of two sites (WO1 -3 and WPO1 -4) in a tropical West Pacific warm pool region was characterized by using molecular phylogenetic analysis. The results of culture-independent samples demonstrated that the dominant clones from both sites were related to Grampositive spore forming genus, Desulfotomaculum, which accounted for 36.8% of all the sequencing clones from Site WP01 - 3 and 62.8% from Site WP01 -4. However, the other SRB group which was generally reported to be predominant in the deep-sea sediments of other regions, δ- subclass of the proteobacteria was found to be in very low percentages. Therefore, it could be speculated that there existed a unique chemical environment in the deep-sea sediment of this warm pool region. When comparing the Desulfotomaculum sp. related sequences from both sites, it was revealed that though the Desulfotomaculum-like sequences from Site WP01 -3 were more diverse than those from Site WP01 -4, all these sequences from both sites showed high similarity and formed a new phylogenetically homogeneous cluster in the Desulfotomaculum genus which had never been reported before. Successful enrichment of SRB was only achieved from samples of Site WP01 -4 and the sequence analysis of culture-dependent samples further confirmed the dominance of Desulfotomaculum genus. But Desulfotomaculum-related sequences from culture-dependent and culture-independent samples belonged to two different clusters respectively. This difference showed the choice of cultivation to the microorganisms.
文摘A study of the genetic structure of an ancient human excavated from the Yikeshu site of Yuanshangdu ancient city in Inner Mongolia and the relationships between the ancient population and the extant populations was carried out. Sequences of the control region and coding region of mtDNA from the ancient human were analyzed by using direct sequencing and restriction-fragment length polymorphism (RFLP) methods, Phylogenetic analysis and multidimensional scaling analysis were also performed on the mtDNA data of the ancient population and 12 extant populations. These results show that the ancient individuals of Yikeshu site can be assigned to D, G, B and Z haplogroups that are prevalent in Duars and Mongolians from Inner Mongolia. The ancient population is also closer to Duar and Mongolian populations in genetic distance than other compared populations. This study reveals that the ancient population from Yikeshu site in the Yuan Dynasty shares a common ancestor with Mongolic-speaking Daur and Mongolian tribes.
基金Supported by the National Natural Science Foundation of China(31201911 31372438)
文摘Porcine epidemic diarrhea(PED)is caused by porcine epidemic diarrhea virus(PEDV),and is characterized by vomiting,diarrhea and dehydration of suckling pigs from 80% to 100% morbidity and 50% to 90% mortality,and resulted in tremendous economic losses to swine industry.The PEDV mainly infects small intestine of pigs,resulting in vacuolar degeneration and necrosis of mucosal epithelium.The IPEC-J2 is a pig intestine epithelial cell line,which is similar to the intestinal environment of piglets,can be used to isolate and identify the PEDV field isolates.In this study,it appeared the PEDV typical postmortem changes and histopathological lesion of degeneration and destruction of small intestine in infected piglets,and IHC identified that the PEDV distributed in the mucosa and submucosa of small intestine mostly.Furthermore,the PEDV HLJ strain was successfully isolated and characterized in the IPEC-J2 cells,and indicated that the IPEC-J2 cell line was sensitive to isolate and adapt the PEDV field strain,and could be utilized to multiply the PEDV rapidly.The S gene analysis indicated that the PEDV HLJ strain was the prevailed virus,belonged to Group 1 with attenuated virulent DR13,SC1402 and J-S2/2015 strains isolated in South Korea and China from 2014 to 2015.This study had important theoretical and practical significances on analyzing genetic variation of the PEDV,understanding the pathogenic characteristics of the virus and developing new vaccines for the PED.
基金Supported by the National Natural Science Foundation of China(31372438)。
文摘Encephalomyocarditis virus(EMCV)is a positive single-stranded small RNA virus without envelope,which can infect a variety of mammals.Swines are the most susceptible animals,which can cause acute myocarditis and respiratory failure in piglets and reproductive failure in pregnant sows.Diseases caused by EMCV have a wide range of effects on the global swine industry.In this study,a strain of EMCV was isolated from a swine aborted fetus in northeast China.It was identified by reverse transcriptase polymerase chain reaction(RT-PCR),electron microscopic observation and indirect immunofluorescence assay.The subsequent results showed that the virus titer of HLJ strain grew to 8.3 lgTCID50 on baby hamster kidney 21(BHK-21)cells.And HLJ strain caused the specific cytopathic effect(CPE)on BHK-21 cells and severe pathological changes in mice.Complete genome sequencing and multiple sequence alignment showed that the homology between HLJ strain and other isolates worldwide was 71.5%-99.7%.Phylogenetic analysis showed that EMCV isolates fell into five clusters:lineageⅠ,Ⅱ,Ⅲ,ⅣandⅤ,based on the nucleotide sequences of the entire open reading frame(ORF)and VP1 gene.HLJ isolate was grouped into lineage I.The analyses of amino acid mutation sites of VP1 protein showed that the amino acids at positions 20 and 54 in VP1 junction were unique to HLJ strain.The isolation of HLJ strain enriched the epidemiological database of EMCV.
基金supported by the National Natural Science Foundation of China(NSFC):(Grant No.32002268)the China Postdoctoral Science Foundation(Grant No.2019M662677)the Wuhan 3551 Optics Valley Talent Program and the Wuhan Talent Program.
文摘Feline calicivirus(FCV)is an important feline pathogen mainly causing upper respiratory tract disease,conjunctivitis,and stomatitis,and it is classifed into genotype I and genotype II.To investigate the prevalence and molecular characteristics of FCV,this study collected 337 cat swab samples from animal hospitals in diferent regions of China from 2019 to 2021.The positive detection rate of FCV was 29.9%(101/337)by RT-PCR.Statistical analysis showed that FCV prevalence was signifcantly associated with living environment(p=0.0004),age(p=0.031)and clinical symptoms(p=0.00),but not with sex(p=0.092)and breed(p=0.171).The 26 strains of FCV were isolated using F81 cells.Phylogenetic analysis showed that 10 isolates belonged to genotype I,and 16 isolates belonged to genotype II.These 26 isolates were highly genetically diverse,of which HB7 isolate had three same virulence-related amino acid loci with VSD strains.Potential loci distinguishing diferent genotypes were identifed from 26 isolates,suggesting the genetic relationship between diferent genotypes.In addition,selection pressure analysis based on capsid protein of 26 isolates revealed that the protein is under diversifying selection.This study reveals the genetic diversity of FCV and provides a reference for the screening of vaccine candidate strains and the development of vaccines with better cross-protection efects.
基金Supported by China Agriculture Research System of MOF and MARA(CARS-170303)“Yunling Industry and Technology Leading Talent”Training Program"Prevention and Control of Sugarcane Pests"(2018LJRC56)Special Fund for the Construction of Modern Agricultural Industry Technology System in Yunnan Province(YNGZTX-4-92)。
文摘[Objectives]This study was conducted to determine the pathogen species and dominant species of sugarcane pokkah boeng in the sugarcane areas of Yunnan in the low-latitude plateau,so as to provide a basis for the pathogenic mechanism,disease resistance breeding and scientific prevention and control of pokkah boeng.[Methods]With 14 pokkah boeng samples collected from different sugarcane areas in Yunnan as materials,pokkah boeng-specific detection primers FvF4/Fv-R4 and Fp-F3/Fp-R3 were designed based on ribosomal DNA non-transcribed spacer(rDNA-ITS)sequences,respectively,and used to perform PCR on Fusarium verticillioides and F.proliferatum.[Results]In 12 of the 14 pokkah boeng samples,two species of pokkah boeng pathogens were detected,and there was a phenomenon of composite infection.Seven composite infection samples were selected for sequence alignment and phylogenetic analysis.The sequences of F.verticillioides(Gen Bank accession number:MZ126549-MZ126555)and F.proliferatum(Gen Bank accession number:MZ102259-MZ102265)from seven composite infection samples shared 98.6%-100%and 100%with F.verticillioides strain 20(Gen Bank accession number:KU508286)and F.proliferatum Dehong strain(GenBank accession number:KJ629482)published in Gen Bank,respectively.The phylogenetic tree showed that the pathogens of sugarcane pokkah boeng in Yunnan were mainly divided into the F.verticillioides group and F.proliferatum group.In the F.verticillioides group,except for ROC 25(Lancang,Yunnan)and Funong10-1405(Maitreya,Yunnan)which were on an independent branch,the remaining five composite infection samples were grouped with F.verticillioides strains from different geographical origins,and were closely related to F.oxysporum Guangxi strain.All strains of F.proliferatum from different geographic origins were clustered into another group.[Conclusions]This study provides a scientific basis for disease resistance breeding and disease prevention and control of sugarcane pokkah boeng.
基金Supported by Science and Technology Major Projects of Guangxi Province(GKAA17204057)Systematic Research Project of Guangxi Key Laboratory of Veterinary Biotechnology(14-045-31-A-5)Fundamental Research Fund of Guangxi Veterinary Research Institute(GKZX 2016-2)
文摘[Objective] The paper was to provide a basis for scientific prevention and control of pigeon Newcastle disease(ND).[Method] The HN gene of eight pigeon NDV strains isolated from different pigeon farms in Guangxi were amplified by RT-PCR,sequenced and analyzed.The molecular evolution characteristics of HN gene of pigeon NDV isolates in Guangxi was discussed.[Result] The nucleotide sequence length of HN gene of the eight NDV isolates was 1 716 bp,encoding 571 amino acids.They belonged to virulent group C,and the gene length characteristic of HN gene accorded with virulent strain.Analysis of nucleotide homologies indicated that the eight NDV isolates shared higher homology with genotype VIb,ranging from 90.4% to 99.5%.Phylogenetic tree analysis demonstrated that the genetic relationship between the eight NDV strains in Gangxi and the NDV isolates from Guangxi,Guangdong,Jilin,Liaoning,Yunnan and Heilongjiang during 2011 and 2013 was close.They were located in the same cladogram branch.[Conclusion] We assume that the eight pigeon NDV isolates in Guangxi all belong to the gene class II genotype VI b NDV.
文摘Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G+C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter.