对传统乳制品开菲尔发酵剂通过菌种分离和纯化得到67株乳酸菌,经过传统形态学分类区分成6种形态类型。在此基础上进行16S r DNA限制性片段长度多态性聚合酶链反应(polymerase chain reaction-restriction fragment length polymorphism,...对传统乳制品开菲尔发酵剂通过菌种分离和纯化得到67株乳酸菌,经过传统形态学分类区分成6种形态类型。在此基础上进行16S r DNA限制性片段长度多态性聚合酶链反应(polymerase chain reaction-restriction fragment length polymorphism,PCR-RFLP)分析法鉴定为4种分子类型,分别为:乳明串株菌(L.lactis)、坚强肠球菌(E.durans)、意大利肠球菌(E.italicus)、嗜热链球菌(S.thermophilus)。其中坚强肠球菌菌数超过50%,占所分离菌株的62.7%,为优势菌。展开更多
Recent advances in the field of microbial and medical ecology emphasize the critical role played by oral bacteria in the delicate dynamic equilibrium of human health and disease, creating the need to define the bacter...Recent advances in the field of microbial and medical ecology emphasize the critical role played by oral bacteria in the delicate dynamic equilibrium of human health and disease, creating the need to define the bacterial communities associated with healthy and non-healthy conditions and to capture shifts in community structure germane to diagnosis. Employing PCR-RFLP of the 16S rDNA gene from metagenomes and plate-wash (cultured) bacteria of oral wash from 10 volunteers, this study evaluated the stability of oral bacteria in healthy subjects and documented community shifts in smokers. Sequence analysis of selected 16S gene amplicons cloned with the Gene Hunter PCR-Trap vector and pCR 4-TOPO cloning kits was conducted to determine the bacteria identity and diversity indices of the two groups. Ribopatterns generated by the restriction enzymes HaeIII and Sau3AI were significantly (p AluI using the GelCompare II software cluster analysis. A stable core of bacteria DNA fingerprint was detected in all healthy subjects, and remained unchanged over the study period of 3 months. Signature bands (1500 bp with HaeIII) in smokers and in non-smokers (800 bp and 700 bp with Sau3A1) were evidently suggesting the presence of potential biomarkers of healthy and non-healthy states. There was no significant difference in the DNA fingerprints of cultured and metagenomic extracts. The genera Xanthomonas, Streptococcus and phylum Candidatus occurred in large numbers in both groups, however, a major shift in composition with the dominance of gram-negative bacteria in smokers compared to healthy subjects was quite remarkable. Taxonomic diversity in smokers was quite high, including members of the genera Rothia, Synechococcus, Neisseria, Thiomargarita and Pyrobaculum. These data highlight the presence of a stable core microbiome amidst a wide diversity, identify a distinct smokers’ cluster and open the way for the search for potential biomarkers for specific diseases.展开更多
根据不同种属细菌的16 S rDNA序列两端的保守性区域设计通用引物,提取菌株的基因组DNA,对菌株的16 S rDNA进行了PCR扩增,对扩增到的目标片段进行了测序,将测序结果与NCBI上已知菌种的16 S rDNA序列进行了BLAST对比,并构建了系统进化树...根据不同种属细菌的16 S rDNA序列两端的保守性区域设计通用引物,提取菌株的基因组DNA,对菌株的16 S rDNA进行了PCR扩增,对扩增到的目标片段进行了测序,将测序结果与NCBI上已知菌种的16 S rDNA序列进行了BLAST对比,并构建了系统进化树。结合传统的形态观察及生理生化特性鉴定,16 S rDNA序列分析结果证实芽孢杆菌Pab02为枯草芽孢杆菌,PAS38为蜡样芽孢杆菌。展开更多
四川省某藏鸡场藏鸡发生以鼻腔与窦发炎、颜面肿胀、流鼻涕和打喷嚏为主要特征的疾病,通过对送检病鸡病原的分离纯化、生化鉴定、16 S rDNA基因的克隆和序列分析诊断为副鸡嗜血杆菌感染,将该株副鸡嗜血杆菌的16 S rDNA序列与GenBank中1...四川省某藏鸡场藏鸡发生以鼻腔与窦发炎、颜面肿胀、流鼻涕和打喷嚏为主要特征的疾病,通过对送检病鸡病原的分离纯化、生化鉴定、16 S rDNA基因的克隆和序列分析诊断为副鸡嗜血杆菌感染,将该株副鸡嗜血杆菌的16 S rDNA序列与GenBank中15株巴氏杆菌科菌株进行同源性分析发现,与6株副鸡嗜血杆菌同源性较高,为94.2%～97.2%,与其它菌株16 S rDNA基因的同源性较低。另外,药敏试验表明,本菌株对菌必治、阿莫西林、庆大霉素、头孢氨噻肟和阿奇霉素等药物敏感。展开更多
以取自四川省不同地区的牦牛粪便、肠道内容物为材料,用MRS琼脂双层培养基进行厌氧培养,分离到50株乳酸菌,经生化鉴定为嗜热链球菌(2株)、乳酸乳球菌(1株)、保加利亚乳杆菌(5株)、嗜粪乳杆菌(10株)、嗜酸乳杆菌(8株)、乳酸乳杆菌(9株)...以取自四川省不同地区的牦牛粪便、肠道内容物为材料,用MRS琼脂双层培养基进行厌氧培养,分离到50株乳酸菌,经生化鉴定为嗜热链球菌(2株)、乳酸乳球菌(1株)、保加利亚乳杆菌(5株)、嗜粪乳杆菌(10株)、嗜酸乳杆菌(8株)、乳酸乳杆菌(9株)、肠乳杆菌(10株)、弯曲乳杆菌(5株)。采用乳酸菌16 S rDNA通用引物,对分离的8种菌的16 S rDNA一段可变区序列进行扩增,均得到大小约470 bp的产物;扩增产物经纯化、测序后与GenBank中标准菌株的核甘酸序列比较,同源性均大于97．5％,同源性分析与生化试验的结果是一致的。证实,牦牛肠道和粪便的乳酸菌较为丰富,且乳杆菌的数量较多,这可能与牦牛复杂的生长环境有关。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
A sulfate reducing bacteria was isolated from mining sewage of Daqing Oilfield by Hungate anaerobic technology. Physiological-biochemical analysis showed that the strain could utilize polyacrylamide as sole carbon and...A sulfate reducing bacteria was isolated from mining sewage of Daqing Oilfield by Hungate anaerobic technology. Physiological-biochemical analysis showed that the strain could utilize polyacrylamide as sole carbon and nitrogen source. The sequence analysis of 16S rDNA illustrated that the similarity of F8 and Desulfovibrio desulfuricans (AF192153) was 99%, and the similarity sequence of dissimilatory sulfite reductase gene (DSR) cloned from the strain and Desulfovibrio desulfuricans (AF273034) was 98%. Their phylogenitic analysis was basically anastomosed, and thus temporarily named as Desulfovibrio desulfuricans F8. The DSR cloned from F8 strain was 2740 bp in length consisting of three ORF, DSRA, DSRB and DSRD as a single operon (DSRABD) regulated by the same operator. DSRA contained typical conservative box of sulfate—sulfite reducing enzyme (SiteⅠand SiteⅡ), which could bind siroheme and [Fe4S4]. DSRB retained a [Fe4S4] binding site, with an uncomplimentary structure for siroheme binding. There was no conservative box in DSRD. Sequence analysis of DSR will provide a theoretical basis for quantitative detection, metabolic pathway modification through gene engineering, and sulfate reducing bacteria (SRB) suppression.展开更多
BACKGROUND This study aimed to identify characteristic gut genera in obese and normal-weight children(8-12 years old)using 16S rDNA sequencing.The research aimed to provide insights for mechanistic studies and prevent...BACKGROUND This study aimed to identify characteristic gut genera in obese and normal-weight children(8-12 years old)using 16S rDNA sequencing.The research aimed to provide insights for mechanistic studies and prevention strategies for childhood obesity.Thirty normal-weight and thirty age-and sex-matched obese children were included.Questionnaires and body measurements were collected,and fecal samples underwent 16S rDNA sequencing.Significant differences in body mass index(BMI)and body-fat percentage were observed between the groups.Analysis of gut microbiota diversity revealed lowerα-diversity in obese children.Differences in gut microbiota composition were found between the two groups.Prevotella and Firmicutes were more abundant in the obese group,while Bacteroides and Sanguibacteroides were more prevalent in the control group.AIM To identify the characteristic gut genera in obese and normal-weight children(8-12-year-old)using 16S rDNA sequencing,and provide a basis for subsequent mechanistic studies and prevention strategies for childhood obesity.METHODS Thirty each normal-weight,1:1 matched for age and sex,and obese children,with an obese status from 2020 to 2022,were included in the control and obese groups,respectively.Basic information was collected through questionnaires and body measurements were obtained from both obese and normal-weight children.Fecal samples were collected from both groups and subjected to 16S rDNA sequencing using an Illumina MiSeq sequencing platform for gut microbiota diversity analysis.RESULTS Significant differences in BMI and body-fat percentage were observed between the two groups.The Ace and Chao1 indices were significantly lower in the obese group than those in the control group,whereas differences were not significant in the Shannon and Simpson indices.Kruskal-Wallis tests indicated significant differences in unweighted and weighted UniFrac distances between the gut microbiota of normal-weight and obese children(P<0.01),suggesting substantial disparities in both the species and quantity of gut microbiota between the two groups.Prevotella,Firmicutes,Bacteroides,and Sanguibacteroides were more abundant in the obese and control groups,respectively.Heatmap results demonstrated significant differences in the gut microbiota composition between obese and normal-weight children.CONCLUSION Obese children exhibited lowerα-diversity in their gut microbiota than did the normal-weight children.Significant differences were observed in the composition of gut microbiota between obese and normal-weight children.展开更多
文摘对传统乳制品开菲尔发酵剂通过菌种分离和纯化得到67株乳酸菌,经过传统形态学分类区分成6种形态类型。在此基础上进行16S r DNA限制性片段长度多态性聚合酶链反应(polymerase chain reaction-restriction fragment length polymorphism,PCR-RFLP)分析法鉴定为4种分子类型,分别为:乳明串株菌(L.lactis)、坚强肠球菌(E.durans)、意大利肠球菌(E.italicus)、嗜热链球菌(S.thermophilus)。其中坚强肠球菌菌数超过50%,占所分离菌株的62.7%,为优势菌。
文摘Recent advances in the field of microbial and medical ecology emphasize the critical role played by oral bacteria in the delicate dynamic equilibrium of human health and disease, creating the need to define the bacterial communities associated with healthy and non-healthy conditions and to capture shifts in community structure germane to diagnosis. Employing PCR-RFLP of the 16S rDNA gene from metagenomes and plate-wash (cultured) bacteria of oral wash from 10 volunteers, this study evaluated the stability of oral bacteria in healthy subjects and documented community shifts in smokers. Sequence analysis of selected 16S gene amplicons cloned with the Gene Hunter PCR-Trap vector and pCR 4-TOPO cloning kits was conducted to determine the bacteria identity and diversity indices of the two groups. Ribopatterns generated by the restriction enzymes HaeIII and Sau3AI were significantly (p AluI using the GelCompare II software cluster analysis. A stable core of bacteria DNA fingerprint was detected in all healthy subjects, and remained unchanged over the study period of 3 months. Signature bands (1500 bp with HaeIII) in smokers and in non-smokers (800 bp and 700 bp with Sau3A1) were evidently suggesting the presence of potential biomarkers of healthy and non-healthy states. There was no significant difference in the DNA fingerprints of cultured and metagenomic extracts. The genera Xanthomonas, Streptococcus and phylum Candidatus occurred in large numbers in both groups, however, a major shift in composition with the dominance of gram-negative bacteria in smokers compared to healthy subjects was quite remarkable. Taxonomic diversity in smokers was quite high, including members of the genera Rothia, Synechococcus, Neisseria, Thiomargarita and Pyrobaculum. These data highlight the presence of a stable core microbiome amidst a wide diversity, identify a distinct smokers’ cluster and open the way for the search for potential biomarkers for specific diseases.
文摘根据不同种属细菌的16 S rDNA序列两端的保守性区域设计通用引物,提取菌株的基因组DNA,对菌株的16 S rDNA进行了PCR扩增,对扩增到的目标片段进行了测序,将测序结果与NCBI上已知菌种的16 S rDNA序列进行了BLAST对比,并构建了系统进化树。结合传统的形态观察及生理生化特性鉴定,16 S rDNA序列分析结果证实芽孢杆菌Pab02为枯草芽孢杆菌,PAS38为蜡样芽孢杆菌。
文摘四川省某藏鸡场藏鸡发生以鼻腔与窦发炎、颜面肿胀、流鼻涕和打喷嚏为主要特征的疾病,通过对送检病鸡病原的分离纯化、生化鉴定、16 S rDNA基因的克隆和序列分析诊断为副鸡嗜血杆菌感染,将该株副鸡嗜血杆菌的16 S rDNA序列与GenBank中15株巴氏杆菌科菌株进行同源性分析发现,与6株副鸡嗜血杆菌同源性较高,为94.2%～97.2%,与其它菌株16 S rDNA基因的同源性较低。另外,药敏试验表明,本菌株对菌必治、阿莫西林、庆大霉素、头孢氨噻肟和阿奇霉素等药物敏感。
文摘以取自四川省不同地区的牦牛粪便、肠道内容物为材料,用MRS琼脂双层培养基进行厌氧培养,分离到50株乳酸菌,经生化鉴定为嗜热链球菌(2株)、乳酸乳球菌(1株)、保加利亚乳杆菌(5株)、嗜粪乳杆菌(10株)、嗜酸乳杆菌(8株)、乳酸乳杆菌(9株)、肠乳杆菌(10株)、弯曲乳杆菌(5株)。采用乳酸菌16 S rDNA通用引物,对分离的8种菌的16 S rDNA一段可变区序列进行扩增,均得到大小约470 bp的产物;扩增产物经纯化、测序后与GenBank中标准菌株的核甘酸序列比较,同源性均大于97．5％,同源性分析与生化试验的结果是一致的。证实,牦牛肠道和粪便的乳酸菌较为丰富,且乳杆菌的数量较多,这可能与牦牛复杂的生长环境有关。
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Sponsored by the National Basic Research and Development (973) Program of China(Grant No.2004CB418505)
文摘A sulfate reducing bacteria was isolated from mining sewage of Daqing Oilfield by Hungate anaerobic technology. Physiological-biochemical analysis showed that the strain could utilize polyacrylamide as sole carbon and nitrogen source. The sequence analysis of 16S rDNA illustrated that the similarity of F8 and Desulfovibrio desulfuricans (AF192153) was 99%, and the similarity sequence of dissimilatory sulfite reductase gene (DSR) cloned from the strain and Desulfovibrio desulfuricans (AF273034) was 98%. Their phylogenitic analysis was basically anastomosed, and thus temporarily named as Desulfovibrio desulfuricans F8. The DSR cloned from F8 strain was 2740 bp in length consisting of three ORF, DSRA, DSRB and DSRD as a single operon (DSRABD) regulated by the same operator. DSRA contained typical conservative box of sulfate—sulfite reducing enzyme (SiteⅠand SiteⅡ), which could bind siroheme and [Fe4S4]. DSRB retained a [Fe4S4] binding site, with an uncomplimentary structure for siroheme binding. There was no conservative box in DSRD. Sequence analysis of DSR will provide a theoretical basis for quantitative detection, metabolic pathway modification through gene engineering, and sulfate reducing bacteria (SRB) suppression.
文摘BACKGROUND This study aimed to identify characteristic gut genera in obese and normal-weight children(8-12 years old)using 16S rDNA sequencing.The research aimed to provide insights for mechanistic studies and prevention strategies for childhood obesity.Thirty normal-weight and thirty age-and sex-matched obese children were included.Questionnaires and body measurements were collected,and fecal samples underwent 16S rDNA sequencing.Significant differences in body mass index(BMI)and body-fat percentage were observed between the groups.Analysis of gut microbiota diversity revealed lowerα-diversity in obese children.Differences in gut microbiota composition were found between the two groups.Prevotella and Firmicutes were more abundant in the obese group,while Bacteroides and Sanguibacteroides were more prevalent in the control group.AIM To identify the characteristic gut genera in obese and normal-weight children(8-12-year-old)using 16S rDNA sequencing,and provide a basis for subsequent mechanistic studies and prevention strategies for childhood obesity.METHODS Thirty each normal-weight,1:1 matched for age and sex,and obese children,with an obese status from 2020 to 2022,were included in the control and obese groups,respectively.Basic information was collected through questionnaires and body measurements were obtained from both obese and normal-weight children.Fecal samples were collected from both groups and subjected to 16S rDNA sequencing using an Illumina MiSeq sequencing platform for gut microbiota diversity analysis.RESULTS Significant differences in BMI and body-fat percentage were observed between the two groups.The Ace and Chao1 indices were significantly lower in the obese group than those in the control group,whereas differences were not significant in the Shannon and Simpson indices.Kruskal-Wallis tests indicated significant differences in unweighted and weighted UniFrac distances between the gut microbiota of normal-weight and obese children(P<0.01),suggesting substantial disparities in both the species and quantity of gut microbiota between the two groups.Prevotella,Firmicutes,Bacteroides,and Sanguibacteroides were more abundant in the obese and control groups,respectively.Heatmap results demonstrated significant differences in the gut microbiota composition between obese and normal-weight children.CONCLUSION Obese children exhibited lowerα-diversity in their gut microbiota than did the normal-weight children.Significant differences were observed in the composition of gut microbiota between obese and normal-weight children.
