PCR-based DNA fingerprinting, REP-PCR(repetitive element PCR), RAPD(randomly amplified polymorphic DNA) and16 S r DNA sequence analyses were used to characterize 23 Acidithiobacillus ferrooxidans strains isolated from...PCR-based DNA fingerprinting, REP-PCR(repetitive element PCR), RAPD(randomly amplified polymorphic DNA) and16 S r DNA sequence analyses were used to characterize 23 Acidithiobacillus ferrooxidans strains isolated from different environments.(GTG)5 and BOXA1 R primer were selected for REP-PCR. Twenty arbitrary primers were used for RAPD to acquire DNA profiles from A. ferrooxidans. Both RAPD and REP-PCR produce complex banding patterns and show good discriminatory ability in differentiating closely related strains of A. ferrooxidans. The strains are clustered into 4 or 5 major groups and reveal genomic diversity using(GTG)5-PCR, BOX-PCR and RAPD analysis. Phylogenetic tree based on 16 S r DNA sequences of 23 strains and related strains shows that they are clustered into two distinct groups. Twelve strains are highly related to a new Acidithiobacillus named Acidithiobacillus ferrivorans. The results indicate that PCR-based methods are effective in revealing genetic diversity among A. ferrooxidans.展开更多
In order to reduce deleterious effect on environment,human health and facilities caused by original sulfides, more attention should be paid to biodesulfurization studying for fossil fuels. In this work, eight isolates...In order to reduce deleterious effect on environment,human health and facilities caused by original sulfides, more attention should be paid to biodesulfurization studying for fossil fuels. In this work, eight isolates were characterized by several DNA-based methods such as BOX element polymerase chain reaction( BOX-PCR), enterobacterial repetitive intergenic consensus( ERIC)-PCR and random amplification of polymorphic DNA( RAPD)-PCR. The desulfurization performance was determined by micro-coulometric method,Gibb's assay and barium sulfate test. It was found out that ERIC-PCR displays a much higher inter-strain heterogeneity compared with using BOX. The length of the primer didnot play the most important role in bacterial classification. The combination of the analysis of repetitive-sequence-based polymerase chain reaction ngerprinting and 16 S r DNA was able to provide more effective way in the separation and identification of bacteria.According to the analysis of 16 S r DNA,the more efficient desulfurization strain should belong to Klebsiella variicola.展开更多
Objective:To determine patterns of antimicrobial resistance,analyze the prevalence of oxacillinase and molecular typing of strains of Acinetobacter baumannii(A.baumannii).Methods:A total of 121 strains of A.baumannii ...Objective:To determine patterns of antimicrobial resistance,analyze the prevalence of oxacillinase and molecular typing of strains of Acinetobacter baumannii(A.baumannii).Methods:A total of 121 strains of A.baumannii were obtained from patients admitted to Imam Hossein and Imam Khomeini Hospitals,Tehran,Iran,from January 2016 to November 2018.Antimicrobial susceptibility testing was performed by Kirby-Bauer disc diffusion method according to the Clinical and Laboratory Standards Institute recommendations.The presence of oxacillinase genes was assessed by polymerase chain reaction(PCR).To determine clonal relatedness,all isolates were subjected to repetitive sequence-based PCR(REP-PCR).Results:The isolates were obtained from 56(46.3%)males and 65(53.7%)females with the mean age of 39.5 years.Colistin with 100.0%sensitivity rate had the highest effect,while ceftriaxone with 16.5%sensitivity rate had the least effect on A.baumannii isolates.In addition,96(79.3%)and 99(81.8%)isolates were resistant to imipenem and meropenem,respectively.A total of 109 isolates(90.0%)exhibited multiple drug resistance with 10 different resistotypes.In total,75(75.7%)of carbapenem resistant isolates were positive for blaOXA-23-like,and 14(14.1%)for blaOXA-24-like gene.The five main clones A,B,C,D,and E were detected in 25(25.2%),36(36.4%),10(10.1%),8(8.0%),and 6(6.1%)of isolates,respectively.Conclusions:Carbapenem-resistant A.baumannii strains are high in the current study.To control the spread of carbapenem-resistant A.baumannii strains,regular monitoring programs are needed.展开更多
为了解不同地区甘薯茎腐病菌Dickeya dadantii种群遗传多样性水平及致病力差异,采用重复序列PCR基因指纹(repetitive element palindromic PCR,REP-PCR)技术和薯片接种方法,对采自广东省、广西壮族自治区和重庆市的6个市区县的59株菌株...为了解不同地区甘薯茎腐病菌Dickeya dadantii种群遗传多样性水平及致病力差异,采用重复序列PCR基因指纹(repetitive element palindromic PCR,REP-PCR)技术和薯片接种方法,对采自广东省、广西壮族自治区和重庆市的6个市区县的59株菌株进行分析。结果表明,5对引物对59株菌株扩增出41个清晰的条带,其中36个为多态性条带,每对引物的扩增条带数在4～10之间,平均为7.2。在物种水平上,有效等位基因数、Nei’s基因多样性指数和Shannon信息指数分别为1.4768、0.2801和0.4186,其中湛江种群多样性最高,南宁种群多样性最低;当遗传相似系数为0.79时,59株菌株可被划分为5个类群,类群划分与菌株来源地间有一定的相关性。此外,不同地区病菌种群间存在明显的致病力差异,其中合浦种群与湛江种群致病力最强,万州种群致病力较弱。表明甘薯茎腐病菌种群具有丰富的遗传多样性,不同地区的病菌种群存在明显的遗传多样性与致病力差异。展开更多
【目的】研究不同地理来源嗜酸硫杆菌的系统发育及其遗传差异,以及基因指纹图谱技术聚类与嗜酸硫杆菌地理来源的相关性。【方法】采用16S-23S r RNA间隔区(ITS)序列建立系统发育树,并结合ERIC和BOXAIR两种引物进行rep-PCR,以及rus基因扩...【目的】研究不同地理来源嗜酸硫杆菌的系统发育及其遗传差异,以及基因指纹图谱技术聚类与嗜酸硫杆菌地理来源的相关性。【方法】采用16S-23S r RNA间隔区(ITS)序列建立系统发育树,并结合ERIC和BOXAIR两种引物进行rep-PCR,以及rus基因扩增,对不同地理来源嗜酸硫杆菌进行分析。【结果】分离自不同样点的23株嗜酸硫杆菌遗传差异显著,依据ITS序列系统发育树被划分为5个大类群,与rep-PCR指纹图谱的分类结果较为接近,其中Acidithiobacillus ferrooxidans在ITS系统发育和BOXAIR-PCR指纹聚类分析中被划分为2个类群,但在ERIC-PCR中归为1个类群,rus基因分组中,在系统发育和聚类分析中处于同一类群的菌株拥有不同类型的rus基因,说明嗜酸硫杆菌的亚铁氧化途径与系统发育类群无明显相关性;ITS基因拥有区分近缘种或亚种的能力,且BOXAIR-PCR的分辨能力较强,非常适于嗜酸硫杆菌的遗传差异分析。展开更多
基金Project(2010CB630901)supported by the National Basic Research Program of China
文摘PCR-based DNA fingerprinting, REP-PCR(repetitive element PCR), RAPD(randomly amplified polymorphic DNA) and16 S r DNA sequence analyses were used to characterize 23 Acidithiobacillus ferrooxidans strains isolated from different environments.(GTG)5 and BOXA1 R primer were selected for REP-PCR. Twenty arbitrary primers were used for RAPD to acquire DNA profiles from A. ferrooxidans. Both RAPD and REP-PCR produce complex banding patterns and show good discriminatory ability in differentiating closely related strains of A. ferrooxidans. The strains are clustered into 4 or 5 major groups and reveal genomic diversity using(GTG)5-PCR, BOX-PCR and RAPD analysis. Phylogenetic tree based on 16 S r DNA sequences of 23 strains and related strains shows that they are clustered into two distinct groups. Twelve strains are highly related to a new Acidithiobacillus named Acidithiobacillus ferrivorans. The results indicate that PCR-based methods are effective in revealing genetic diversity among A. ferrooxidans.
基金National Natural Science Foundations of China(Nos.41302079,21176145)Project of Shandong Province Higher Educational Science and Technology Program,China(No.J13LD54)
文摘In order to reduce deleterious effect on environment,human health and facilities caused by original sulfides, more attention should be paid to biodesulfurization studying for fossil fuels. In this work, eight isolates were characterized by several DNA-based methods such as BOX element polymerase chain reaction( BOX-PCR), enterobacterial repetitive intergenic consensus( ERIC)-PCR and random amplification of polymorphic DNA( RAPD)-PCR. The desulfurization performance was determined by micro-coulometric method,Gibb's assay and barium sulfate test. It was found out that ERIC-PCR displays a much higher inter-strain heterogeneity compared with using BOX. The length of the primer didnot play the most important role in bacterial classification. The combination of the analysis of repetitive-sequence-based polymerase chain reaction ngerprinting and 16 S r DNA was able to provide more effective way in the separation and identification of bacteria.According to the analysis of 16 S r DNA,the more efficient desulfurization strain should belong to Klebsiella variicola.
文摘Objective:To determine patterns of antimicrobial resistance,analyze the prevalence of oxacillinase and molecular typing of strains of Acinetobacter baumannii(A.baumannii).Methods:A total of 121 strains of A.baumannii were obtained from patients admitted to Imam Hossein and Imam Khomeini Hospitals,Tehran,Iran,from January 2016 to November 2018.Antimicrobial susceptibility testing was performed by Kirby-Bauer disc diffusion method according to the Clinical and Laboratory Standards Institute recommendations.The presence of oxacillinase genes was assessed by polymerase chain reaction(PCR).To determine clonal relatedness,all isolates were subjected to repetitive sequence-based PCR(REP-PCR).Results:The isolates were obtained from 56(46.3%)males and 65(53.7%)females with the mean age of 39.5 years.Colistin with 100.0%sensitivity rate had the highest effect,while ceftriaxone with 16.5%sensitivity rate had the least effect on A.baumannii isolates.In addition,96(79.3%)and 99(81.8%)isolates were resistant to imipenem and meropenem,respectively.A total of 109 isolates(90.0%)exhibited multiple drug resistance with 10 different resistotypes.In total,75(75.7%)of carbapenem resistant isolates were positive for blaOXA-23-like,and 14(14.1%)for blaOXA-24-like gene.The five main clones A,B,C,D,and E were detected in 25(25.2%),36(36.4%),10(10.1%),8(8.0%),and 6(6.1%)of isolates,respectively.Conclusions:Carbapenem-resistant A.baumannii strains are high in the current study.To control the spread of carbapenem-resistant A.baumannii strains,regular monitoring programs are needed.
文摘为了解不同地区甘薯茎腐病菌Dickeya dadantii种群遗传多样性水平及致病力差异,采用重复序列PCR基因指纹(repetitive element palindromic PCR,REP-PCR)技术和薯片接种方法,对采自广东省、广西壮族自治区和重庆市的6个市区县的59株菌株进行分析。结果表明,5对引物对59株菌株扩增出41个清晰的条带,其中36个为多态性条带,每对引物的扩增条带数在4～10之间,平均为7.2。在物种水平上,有效等位基因数、Nei’s基因多样性指数和Shannon信息指数分别为1.4768、0.2801和0.4186,其中湛江种群多样性最高,南宁种群多样性最低;当遗传相似系数为0.79时,59株菌株可被划分为5个类群,类群划分与菌株来源地间有一定的相关性。此外,不同地区病菌种群间存在明显的致病力差异,其中合浦种群与湛江种群致病力最强,万州种群致病力较弱。表明甘薯茎腐病菌种群具有丰富的遗传多样性,不同地区的病菌种群存在明显的遗传多样性与致病力差异。
文摘【目的】研究不同地理来源嗜酸硫杆菌的系统发育及其遗传差异,以及基因指纹图谱技术聚类与嗜酸硫杆菌地理来源的相关性。【方法】采用16S-23S r RNA间隔区(ITS)序列建立系统发育树,并结合ERIC和BOXAIR两种引物进行rep-PCR,以及rus基因扩增,对不同地理来源嗜酸硫杆菌进行分析。【结果】分离自不同样点的23株嗜酸硫杆菌遗传差异显著,依据ITS序列系统发育树被划分为5个大类群,与rep-PCR指纹图谱的分类结果较为接近,其中Acidithiobacillus ferrooxidans在ITS系统发育和BOXAIR-PCR指纹聚类分析中被划分为2个类群,但在ERIC-PCR中归为1个类群,rus基因分组中,在系统发育和聚类分析中处于同一类群的菌株拥有不同类型的rus基因,说明嗜酸硫杆菌的亚铁氧化途径与系统发育类群无明显相关性;ITS基因拥有区分近缘种或亚种的能力,且BOXAIR-PCR的分辨能力较强,非常适于嗜酸硫杆菌的遗传差异分析。
