Antimicrobial proteins and peptides had been found from a wide variety of organisms in the last few years These molecules have attracted much research interest because of their biochemical diversity, broad specificity...Antimicrobial proteins and peptides had been found from a wide variety of organisms in the last few years These molecules have attracted much research interest because of their biochemical diversity, broad specificity on anti-viral, anti-bacterial, anti-fungi, anti-protozoan parasites, anti-tumoural, and wound-healing effects. Antimicrobial proteins and peptides play key roles in innate immunity. They interact directly with bacteria and kill them. The brown-spotted grouper, Epinephelusfario, is an important marine fish cultured in southem China. Recently, bacteria and virus have caused high mortality in E. fario cultures, but its endogenous antimicrobial peptides and proteins have not been explored. An antimicrobial component was found from the skin homogenate of E. fario. After the skin homogenate was digested with trypsin, its antimicrobial activity was lost, which showed that the antimicrobial component is a protein. The antimicrobial protein （Efap） was purified from the skin homogenate of E. fario by successive ion-exchange and gel filtration chromatography. Efap was demonstrated to be single protein band by SDS-PAGE, with the apparent molecular weight of 41 kD. Efap exhibited antimicrobial activity both for the Gram-positive bacteria, Staphylococcus aureus, Micrococcus luteus and Bacillus subtilis, and for the Gram-negative bacteria, Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio fluvialis, Pasteurella multocida, Aeromonas hydrophila, Eschrrichiu coli, and Pseudomonas aeruginosa. Except A. hydrophila, P. aeruginosa, and E. coli （MIC〉20 mol/L）, most of the tested Gram-negative bacteria were sensitive to Efap （MIC〈20 mol/L）. Interestingly, Efap showed potent antimicrobial activity against Gram-positive bacteria S. aureus （MIC 5-10 mol/L） but comparatively weak antimicrobial activity against M. luteus and B. subtilis. The broad antimicrobial activities of Efap suggest that it contributes to the innate host defence of E. fario.展开更多
A new method was used to preparing genomic DNA from Microbacterium sp.quickly and efficiently.DNA quantity and purity was measured by UV absorbance.Integrity of the genomic DNA was tested by agarose gel eletrophoresis...A new method was used to preparing genomic DNA from Microbacterium sp.quickly and efficiently.DNA quantity and purity was measured by UV absorbance.Integrity of the genomic DNA was tested by agarose gel eletrophoresis.The DNA prepared by this method was sufficiently pure for PCR.This method saves time and cost,practices easily as well.展开更多
In quorum sensing （QS） process, bacteria regulate gene expression by utilizing small signaling molecules called autoinducers in response to a variety of environmental cues. Autoinducer 2 （AI-2）, a QS signaling mol...In quorum sensing （QS） process, bacteria regulate gene expression by utilizing small signaling molecules called autoinducers in response to a variety of environmental cues. Autoinducer 2 （AI-2）, a QS signaling molecule proposed to be involved in interspecies communication, is produced by many species of gram-negative and gram-positive bacteria. In Escherichia coil and Salmonella typhimurium, the extracellular AI-2 is imported into the cell by a transporter encoded by the lsr operon. Upstream of the lsr operon, there is a divergently transcribed gene encoding LsrR, which was reported previously to repress the transcription of the lsr operon and itself. Here, we have demonstrated for the first time that LsrR represses the transcription of the lsr operon and itself by directly binding to their promoters using gel shift and DNase I footprinting assays. The β-galactosidase reporter assays further suggest that two motifs in both the lsrR and lsrA promoter regions are crucial for the LsrR binding. Furthermore, in agreement with the conclusion that phosphorylated AI-2 can relieve the repression of LsrR in previous studies, our data show that phospho- AI-2 renders LsrR unable to bind to its own promoter in vitro.展开更多
The culturable bacterial population and phospholipid fatty acid （PLFA） profile of casing soil were investigated at different mushroom （Agaricus bisporus） cropping stages. The change in soil bacterial PLFAs was alw...The culturable bacterial population and phospholipid fatty acid （PLFA） profile of casing soil were investigated at different mushroom （Agaricus bisporus） cropping stages. The change in soil bacterial PLFAs was always accompanied by a change in the soil eulturable bacterial population in the first flush. Comparatively higher culturable bacterial population and bacterial PLFAs were found in the casing soil at the primordia formation stage of the first flush. There was a significant increase in the ratio of fungal to bacterial PLFAs during mushroom growth. Multivariate analysis of PLFA data demonstrated that the mushroom cropping stage could considerably affect the microbial community structure of the casing soil. The bacterial population increased significantly from casing soil application to the primordia formation stage of the first flush. Casing soil application resulted in an increase in the ratio of gram-negative bacterial PLFAs to gram-positive bacterial PLFAs, suggesting that some gram-negative bacteria might play an important role in mushroom sporophore initiation.展开更多
The efficiency of advanced membranes towards removal of general and specific microbes from wastewater was investigated. The treatment included a subsequent system of activated sludge, ultrafiltration （hollow fibre me...The efficiency of advanced membranes towards removal of general and specific microbes from wastewater was investigated. The treatment included a subsequent system of activated sludge, ultrafiltration （hollow fibre membranes with 100 kDa cut-off, and spiral wound membranes with 20 kDa cut-off）, and RO （reverse osmosis）. The removal evaluation of screened microbes present in treated wastewater showed that hollow fibre membrane rejected only 1 log （90% rejection） of the TPC （total microbial count）, TC （total coliforms）, and FC （faecal coliforms）. A higher effectiveness was observed with spiral wound, removing 2-3 logs （99%-99.9%） of TPC and complete rejection of TC and FC. The RO system was successful in total rejection of all received bacteria. The removal evaluation of inoculated specific types of bacteria showed that the hollow membranes removed 2 logs （99%） of inoculated E. coli （10^7-10^8 cfu/mL inoculum）, 2-3 logs （99%-99.9%） of Enterococus spp. （10^7-10^10 cfu/mL inoculum）, 1-2 logs （90%-99%） of Salmonella （10^8-10^10 cfu/mL inoculum） and 1-2 logs （90%-99%） of Shigella （10^5-10^6 cfu/mL inoculum）. The spiral wound was significantly efficient in rejecting further 3 logs of E. coil, 5 logs of Enterococus spp., 4 logs of Salmonella, and a complete rejection of all received bacteria was accomplished by RO membrane. The results indicate that Gram positive bacteria were removed much more efficiently compared to the Gram negative ones, the rationale behind such behaviour is based on cell walls elasticity.展开更多
Marine sponge Tedania anhelans distributes throughout the intertidal zone of Fujian, southeastern China, and is a potential source of natural bioactive products. The sponge harbors a large number of bacterial groups t...Marine sponge Tedania anhelans distributes throughout the intertidal zone of Fujian, southeastern China, and is a potential source of natural bioactive products. The sponge harbors a large number of bacterial groups that have been identified using various techniques, including fluorescent in situ hybridization （FISH）. Fractionation of dissociated sponge allowed isolation of 25 bacterial species. Based on 16S rRNA gene sequencing, phylogenetic analysis attributed most of these eubacteria to cL-Proteobacteria, y-Proteobacteria, Cytophaga/Flavobacterium/Bacteroidetes （CFB group）, and the family Bacillaceae of Gram-positive bacteria. In sequence similarity, five putatively novel species were identified with less than 98% similarity to other strains in the NCBI database. Tests for antimicrobial activities were performed against Gram-positive bacteria, Gram-negative bacteria, fungi, antitumor indicators Escherichia coli 343/591 （with DNA repair deficiency）, regular E. coli 343/636 （with different DNA repair capacity）, and 10 bacterial isolates exhibited inhibitory bioactivities. Among these strains, three isolates were detected involving function gene NRPS-A domains, which were most closely related to the amino acid sequences of linear gramicidin synthetase and pyoverdine synthetase. These results contribute to our knowledge of the microbes associated with marine sponges and further reveal novel bacterial resources for the screening of bioactive marine natural products.展开更多
Our solar system＇s cyclic order explains the sudden appearance of the Advanced Sumerians and Pharaohs around the time of the Atlantean and Mayan destruction. Certainly past advanced civilizations do point to the cycl...Our solar system＇s cyclic order explains the sudden appearance of the Advanced Sumerians and Pharaohs around the time of the Atlantean and Mayan destruction. Certainly past advanced civilizations do point to the cyclic rise and fall of human cultures extending much farther back into ＂prehistory＂ than currently accepted. Ancients believed the universe was concentric heavens, there is evidence of the ancient knowledge of the sun＇s processional cycle of almost 26,000 years, leading to the coup of north and south poles. Edmund Halley wrote about the photon belt that periodically encases the Pleiades constellation＇s eight suns. Halley proposed planet Earth was composed of five concentric earths. In 1950s Doctors Watson and Crick discovered a third separated strand in the double helix. Now energies from the Photon Belt are recalibrating dormant DNA strands, where originally humanity was endowed with 12 DNA strands. Every culture developed their legend of the perfect Human who emerges at the end of human evolution, these prophecies also met with the Abrahamic religions concerning the end＇s signs and the return of paradise on Earth. Christ and the Quran spoke of a light consciousness that succeeds in the earth and the succession of angel like humans before the end.展开更多
Plants of Baccharis （Asteraceae） genus are commonly known in Argentina as ＂carqueja＂. The antimicrobial activity and minimal inhibitory concentration of B. articulata, B. trimera and B. crispa aqueous and ethanoli...Plants of Baccharis （Asteraceae） genus are commonly known in Argentina as ＂carqueja＂. The antimicrobial activity and minimal inhibitory concentration of B. articulata, B. trimera and B. crispa aqueous and ethanolic extracts were evaluated by using the micro-well dilution method. Previously, the components of extracts were analyzed by spectroscopial means. Gram-positive bacteria were more sensitive to Baccharis species extracts than Gram-negative bacteria. Out of 3 plant species, B. trimera showed significant antibacterial activity and aqueous and ethanolic extracts were active against Staphylococcus aureus （MIC = 2,500 μg/mL and 1,250 μg/mL, respectively） and Listeria monocytogenes （MIC = 625 μg/mL and 625 μg/mL, respectively）. All ethanolic extracts inhibited the growth of the selected Gram-positive （MIC values ranged between 625 μg/mL and 1,250 μg/mL）. Therefore, all Gram-negative bacteria were resistant to the ethanolic and aqueous extracts tested. One flavone, genkawanin, was identified from the three ethanolic extracts as the responsible of antibacterial activity. Two terpenes, hawtriwaic acid and bacrispine, were identified from ethanolic extract of B. crispa and B. trimera as the responsibles of antibacterial activity. These preliminary studies corroborated the antimicrobial activity of the selected plants used in folklore medicine. Therefore, they could be potential sources of new antimicrobial agents used in treatment of infectious diseases.展开更多
基金Key Research Program for International Cooperation(2005DFA30610)Program for New Century Excellent Talents in University(NCET-05-0755)+2 种基金National Natural Science Foundation(30700128)Natural Science Foundation of Hainan Province(80623)Research Foundation of Education Department of Hainan Province(Hj200731)
文摘Antimicrobial proteins and peptides had been found from a wide variety of organisms in the last few years These molecules have attracted much research interest because of their biochemical diversity, broad specificity on anti-viral, anti-bacterial, anti-fungi, anti-protozoan parasites, anti-tumoural, and wound-healing effects. Antimicrobial proteins and peptides play key roles in innate immunity. They interact directly with bacteria and kill them. The brown-spotted grouper, Epinephelusfario, is an important marine fish cultured in southem China. Recently, bacteria and virus have caused high mortality in E. fario cultures, but its endogenous antimicrobial peptides and proteins have not been explored. An antimicrobial component was found from the skin homogenate of E. fario. After the skin homogenate was digested with trypsin, its antimicrobial activity was lost, which showed that the antimicrobial component is a protein. The antimicrobial protein （Efap） was purified from the skin homogenate of E. fario by successive ion-exchange and gel filtration chromatography. Efap was demonstrated to be single protein band by SDS-PAGE, with the apparent molecular weight of 41 kD. Efap exhibited antimicrobial activity both for the Gram-positive bacteria, Staphylococcus aureus, Micrococcus luteus and Bacillus subtilis, and for the Gram-negative bacteria, Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio fluvialis, Pasteurella multocida, Aeromonas hydrophila, Eschrrichiu coli, and Pseudomonas aeruginosa. Except A. hydrophila, P. aeruginosa, and E. coli （MIC〉20 mol/L）, most of the tested Gram-negative bacteria were sensitive to Efap （MIC〈20 mol/L）. Interestingly, Efap showed potent antimicrobial activity against Gram-positive bacteria S. aureus （MIC 5-10 mol/L） but comparatively weak antimicrobial activity against M. luteus and B. subtilis. The broad antimicrobial activities of Efap suggest that it contributes to the innate host defence of E. fario.
文摘A new method was used to preparing genomic DNA from Microbacterium sp.quickly and efficiently.DNA quantity and purity was measured by UV absorbance.Integrity of the genomic DNA was tested by agarose gel eletrophoresis.The DNA prepared by this method was sufficiently pure for PCR.This method saves time and cost,practices easily as well.
基金We thank our colleagues J Zang and X Liu for their technical assistance in protein purification. This work was supported by the One Hundred Talent Project of the Chinese Academy of Sciences and the National Natural Science Foundation of China （50738006）.
文摘In quorum sensing （QS） process, bacteria regulate gene expression by utilizing small signaling molecules called autoinducers in response to a variety of environmental cues. Autoinducer 2 （AI-2）, a QS signaling molecule proposed to be involved in interspecies communication, is produced by many species of gram-negative and gram-positive bacteria. In Escherichia coil and Salmonella typhimurium, the extracellular AI-2 is imported into the cell by a transporter encoded by the lsr operon. Upstream of the lsr operon, there is a divergently transcribed gene encoding LsrR, which was reported previously to repress the transcription of the lsr operon and itself. Here, we have demonstrated for the first time that LsrR represses the transcription of the lsr operon and itself by directly binding to their promoters using gel shift and DNase I footprinting assays. The β-galactosidase reporter assays further suggest that two motifs in both the lsrR and lsrA promoter regions are crucial for the LsrR binding. Furthermore, in agreement with the conclusion that phosphorylated AI-2 can relieve the repression of LsrR in previous studies, our data show that phospho- AI-2 renders LsrR unable to bind to its own promoter in vitro.
基金Project supported by the National Natural Science Foundation of China (No.30671207)the Key Program of Science and Technology Plan of Zhejiang Province, China (No.2003C32042)the Scientific Research Foundation for the Returned Overseas Chinese Scholars, Ministry of Education, China
文摘The culturable bacterial population and phospholipid fatty acid （PLFA） profile of casing soil were investigated at different mushroom （Agaricus bisporus） cropping stages. The change in soil bacterial PLFAs was always accompanied by a change in the soil eulturable bacterial population in the first flush. Comparatively higher culturable bacterial population and bacterial PLFAs were found in the casing soil at the primordia formation stage of the first flush. There was a significant increase in the ratio of fungal to bacterial PLFAs during mushroom growth. Multivariate analysis of PLFA data demonstrated that the mushroom cropping stage could considerably affect the microbial community structure of the casing soil. The bacterial population increased significantly from casing soil application to the primordia formation stage of the first flush. Casing soil application resulted in an increase in the ratio of gram-negative bacterial PLFAs to gram-positive bacterial PLFAs, suggesting that some gram-negative bacteria might play an important role in mushroom sporophore initiation.
文摘The efficiency of advanced membranes towards removal of general and specific microbes from wastewater was investigated. The treatment included a subsequent system of activated sludge, ultrafiltration （hollow fibre membranes with 100 kDa cut-off, and spiral wound membranes with 20 kDa cut-off）, and RO （reverse osmosis）. The removal evaluation of screened microbes present in treated wastewater showed that hollow fibre membrane rejected only 1 log （90% rejection） of the TPC （total microbial count）, TC （total coliforms）, and FC （faecal coliforms）. A higher effectiveness was observed with spiral wound, removing 2-3 logs （99%-99.9%） of TPC and complete rejection of TC and FC. The RO system was successful in total rejection of all received bacteria. The removal evaluation of inoculated specific types of bacteria showed that the hollow membranes removed 2 logs （99%） of inoculated E. coli （10^7-10^8 cfu/mL inoculum）, 2-3 logs （99%-99.9%） of Enterococus spp. （10^7-10^10 cfu/mL inoculum）, 1-2 logs （90%-99%） of Salmonella （10^8-10^10 cfu/mL inoculum） and 1-2 logs （90%-99%） of Shigella （10^5-10^6 cfu/mL inoculum）. The spiral wound was significantly efficient in rejecting further 3 logs of E. coil, 5 logs of Enterococus spp., 4 logs of Salmonella, and a complete rejection of all received bacteria was accomplished by RO membrane. The results indicate that Gram positive bacteria were removed much more efficiently compared to the Gram negative ones, the rationale behind such behaviour is based on cell walls elasticity.
基金Supported by the Natural Science Foundation of Fujian Province,China(No.2011J01245)the Fundamental Research Funds for the Central Universities(No.2010121034)
文摘Marine sponge Tedania anhelans distributes throughout the intertidal zone of Fujian, southeastern China, and is a potential source of natural bioactive products. The sponge harbors a large number of bacterial groups that have been identified using various techniques, including fluorescent in situ hybridization （FISH）. Fractionation of dissociated sponge allowed isolation of 25 bacterial species. Based on 16S rRNA gene sequencing, phylogenetic analysis attributed most of these eubacteria to cL-Proteobacteria, y-Proteobacteria, Cytophaga/Flavobacterium/Bacteroidetes （CFB group）, and the family Bacillaceae of Gram-positive bacteria. In sequence similarity, five putatively novel species were identified with less than 98% similarity to other strains in the NCBI database. Tests for antimicrobial activities were performed against Gram-positive bacteria, Gram-negative bacteria, fungi, antitumor indicators Escherichia coli 343/591 （with DNA repair deficiency）, regular E. coli 343/636 （with different DNA repair capacity）, and 10 bacterial isolates exhibited inhibitory bioactivities. Among these strains, three isolates were detected involving function gene NRPS-A domains, which were most closely related to the amino acid sequences of linear gramicidin synthetase and pyoverdine synthetase. These results contribute to our knowledge of the microbes associated with marine sponges and further reveal novel bacterial resources for the screening of bioactive marine natural products.
文摘Our solar system＇s cyclic order explains the sudden appearance of the Advanced Sumerians and Pharaohs around the time of the Atlantean and Mayan destruction. Certainly past advanced civilizations do point to the cyclic rise and fall of human cultures extending much farther back into ＂prehistory＂ than currently accepted. Ancients believed the universe was concentric heavens, there is evidence of the ancient knowledge of the sun＇s processional cycle of almost 26,000 years, leading to the coup of north and south poles. Edmund Halley wrote about the photon belt that periodically encases the Pleiades constellation＇s eight suns. Halley proposed planet Earth was composed of five concentric earths. In 1950s Doctors Watson and Crick discovered a third separated strand in the double helix. Now energies from the Photon Belt are recalibrating dormant DNA strands, where originally humanity was endowed with 12 DNA strands. Every culture developed their legend of the perfect Human who emerges at the end of human evolution, these prophecies also met with the Abrahamic religions concerning the end＇s signs and the return of paradise on Earth. Christ and the Quran spoke of a light consciousness that succeeds in the earth and the succession of angel like humans before the end.
文摘Plants of Baccharis （Asteraceae） genus are commonly known in Argentina as ＂carqueja＂. The antimicrobial activity and minimal inhibitory concentration of B. articulata, B. trimera and B. crispa aqueous and ethanolic extracts were evaluated by using the micro-well dilution method. Previously, the components of extracts were analyzed by spectroscopial means. Gram-positive bacteria were more sensitive to Baccharis species extracts than Gram-negative bacteria. Out of 3 plant species, B. trimera showed significant antibacterial activity and aqueous and ethanolic extracts were active against Staphylococcus aureus （MIC = 2,500 μg/mL and 1,250 μg/mL, respectively） and Listeria monocytogenes （MIC = 625 μg/mL and 625 μg/mL, respectively）. All ethanolic extracts inhibited the growth of the selected Gram-positive （MIC values ranged between 625 μg/mL and 1,250 μg/mL）. Therefore, all Gram-negative bacteria were resistant to the ethanolic and aqueous extracts tested. One flavone, genkawanin, was identified from the three ethanolic extracts as the responsible of antibacterial activity. Two terpenes, hawtriwaic acid and bacrispine, were identified from ethanolic extract of B. crispa and B. trimera as the responsibles of antibacterial activity. These preliminary studies corroborated the antimicrobial activity of the selected plants used in folklore medicine. Therefore, they could be potential sources of new antimicrobial agents used in treatment of infectious diseases.
