利用16S-23S rRNA ITS AFLP指纹图谱技术监控四川传统米酒发酵过程中原核微生物的演替,并结合米酒发酵过程中理化因子的动态变化对其演替过程进行了分析。研究结果表明,米酒发酵过程中,随着酒曲的接入,米酒醅中原核微生物伴随米酒理化...利用16S-23S rRNA ITS AFLP指纹图谱技术监控四川传统米酒发酵过程中原核微生物的演替,并结合米酒发酵过程中理化因子的动态变化对其演替过程进行了分析。研究结果表明,米酒发酵过程中,随着酒曲的接入,米酒醅中原核微生物伴随米酒理化因子的动态变化而发生群落演替。在适应期和发酵期,米酒醅中的原核微生物群落分别聚成群I和群II,二者相关系数为0.49。群II中,在相关系数0.638水平上又分为IIA和IIB两个分支。分支IIA又进一步分为IIA1和IIA2两簇,相关系数为0.73。簇IIA2中主要发生的是发酵旺盛期微生物的演替;簇IIA1中I,IA1-1和IIA1-2亚簇分别表示发酵前期、发酵后期米酒醅中的原核微生物群落演替,二者聚集于相关系数0.80。其中I,IA1-2中,发酵52 h和55 h的米酒醅中原核微生物群落几乎相似,二者群落相关系数为1.0。展开更多
目的利用16 s-23 s rRNA间隔区(ITS)的多态性,对中国布鲁氏菌种间或种内生物型进行鉴别,评价ITS作为基因标识物的意义,寻找适合布鲁氏菌分型研究的基因标识物。方法应用聚合酶链反应-单链构象多态性(PCR-SSCP)分析技术,对中国120株布鲁...目的利用16 s-23 s rRNA间隔区(ITS)的多态性,对中国布鲁氏菌种间或种内生物型进行鉴别,评价ITS作为基因标识物的意义,寻找适合布鲁氏菌分型研究的基因标识物。方法应用聚合酶链反应-单链构象多态性(PCR-SSCP)分析技术,对中国120株布鲁氏菌的ITS进行分析和筛选,测序结果与Genbank中的布鲁氏菌ITS序列进行比较分析。结果对16 s-23 s rRNA间隔区的SSCP结果分析,得到4种不同的带型(ⅠI、I、Ⅲ、Ⅳ),测序序列有3个位点的差异,达到99.87%的一致性。结论中国布鲁氏菌的ITS序列高度保守,具有一定探讨其作为布鲁氏菌属种内分型的基因标识的价值。展开更多
Objective To establish the specific 16S-23S rRNA gene spacer regions in different bacteria using polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), DNA cloning and sequences analysis. M...Objective To establish the specific 16S-23S rRNA gene spacer regions in different bacteria using polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), DNA cloning and sequences analysis. Methods A pair of primers were selected from highly conserved sequences adjacent to the 16S-23S rRNA spacer region. Bacterial DNA from sixty-one strains of standard bacteria and corresponding clinical isolates representative of 20 genera and 26 species was amplified by PCR, and further analyzed by RFLP, DNA cloning and sequences analysis. Furthermore, all specimens were examined by bacterial culturing and PCR-RFLP analysis. The evaluation of these assays in practical clinic practice was also discussed.Results Restriction enzyme analysis revealed one, two or three bands or more observed among the 26 different standard strains. The sensitivity of PCR reached 2.5 colony-forming unit (CFU), and there was no cross reaction with human genomic DNA, fungus or virus. Fourteen species could be distinguished immediately by PCR, while another 10 species were further identified by Hinf Ⅰ or Alu Ⅰ digestion. The only difference between K.pneumoniae and E.durans was located at the site of the 779th nucleotide according to the sequence analysis and only XmaⅢ digestion could distinguish one from another. Of 42 specimens from septicemic neonates, 15 were identified as positive by blood culture at a rate of 35.7%. However, 27 specimens identified as positive by PCR, with a rate of 64.2%, a method significantly more effective than blood culture (P<0.01). Of 6 cerebrospinal fluid (CSF) specimens, one tested positive for S.epidermidis was also positive by PCR, two culture negative were positive by PCR and diagnosed as S.epidermidis according to the DNA pattern. One positive for C.neoformans was negative by PCR. The other two specimens were negative by both PCR and culture.Conclusions The method of detecting bacterial 16S-23S rRNA spacer regions using PCR-RFLP techniques was specific, sensitive, rapid and accurate in providing a new technique for detecting pathogens in clinical bacterial infections.展开更多
文摘目的利用16 s-23 s rRNA间隔区(ITS)的多态性,对中国布鲁氏菌种间或种内生物型进行鉴别,评价ITS作为基因标识物的意义,寻找适合布鲁氏菌分型研究的基因标识物。方法应用聚合酶链反应-单链构象多态性(PCR-SSCP)分析技术,对中国120株布鲁氏菌的ITS进行分析和筛选,测序结果与Genbank中的布鲁氏菌ITS序列进行比较分析。结果对16 s-23 s rRNA间隔区的SSCP结果分析,得到4种不同的带型(ⅠI、I、Ⅲ、Ⅳ),测序序列有3个位点的差异,达到99.87%的一致性。结论中国布鲁氏菌的ITS序列高度保守,具有一定探讨其作为布鲁氏菌属种内分型的基因标识的价值。
基金ThisprojectwassupportedbytheZhejiangProvincalNaturalScienceFoundation (No 39842 6 )
文摘Objective To establish the specific 16S-23S rRNA gene spacer regions in different bacteria using polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), DNA cloning and sequences analysis. Methods A pair of primers were selected from highly conserved sequences adjacent to the 16S-23S rRNA spacer region. Bacterial DNA from sixty-one strains of standard bacteria and corresponding clinical isolates representative of 20 genera and 26 species was amplified by PCR, and further analyzed by RFLP, DNA cloning and sequences analysis. Furthermore, all specimens were examined by bacterial culturing and PCR-RFLP analysis. The evaluation of these assays in practical clinic practice was also discussed.Results Restriction enzyme analysis revealed one, two or three bands or more observed among the 26 different standard strains. The sensitivity of PCR reached 2.5 colony-forming unit (CFU), and there was no cross reaction with human genomic DNA, fungus or virus. Fourteen species could be distinguished immediately by PCR, while another 10 species were further identified by Hinf Ⅰ or Alu Ⅰ digestion. The only difference between K.pneumoniae and E.durans was located at the site of the 779th nucleotide according to the sequence analysis and only XmaⅢ digestion could distinguish one from another. Of 42 specimens from septicemic neonates, 15 were identified as positive by blood culture at a rate of 35.7%. However, 27 specimens identified as positive by PCR, with a rate of 64.2%, a method significantly more effective than blood culture (P<0.01). Of 6 cerebrospinal fluid (CSF) specimens, one tested positive for S.epidermidis was also positive by PCR, two culture negative were positive by PCR and diagnosed as S.epidermidis according to the DNA pattern. One positive for C.neoformans was negative by PCR. The other two specimens were negative by both PCR and culture.Conclusions The method of detecting bacterial 16S-23S rRNA spacer regions using PCR-RFLP techniques was specific, sensitive, rapid and accurate in providing a new technique for detecting pathogens in clinical bacterial infections.
