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1.
丁香假单胞菌猕猴桃致病变种生物型3(Pseudomonas syringae pv. actinidiae biovar 3,Psa3)是猕猴桃溃疡病菌的世界流行群体,但仅在中国存在复杂的遗传多样性。开发适于Psa3群体分型的MLVA(multilocus variable-number tandem-repeat analysis)技术是探索中国Psa3起源与流行学特性的基础。本研究对7个Psa3菌株进行了全基因组测序,结合已公布的86个全基因组数据,进行比较分析发现,中国Psa3至少存在7个亚群;在各亚群间存在多态性的24个串联重复序列中,其中10个可以通过琼脂糖凝胶电泳区分开且变异指数合适,据此建立了适于Psa3的MLVA技术。采用该技术对分别来自贵州和陕西的62和9个Psa3菌株进行群体分型,分型结果与全基因组分析高度一致,证明该MLVA体系分型准确。MLVA分型结果表明:贵州主产区修文县Psa3有3个MLVA群体,其中亚群4的组内分化明显,代表最早发生的群体;而亚群 1和3的结构单一,且多在新果园发现,是新传入群体。总之,本研究建立了一套可用于Psa3群体分型的MLVA技术,将有助于解析中国各猕猴桃产区Psa3群体结构,以及探索中国Psa3的起源、传播和流行学特征。 相似文献
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The aims of this study were to investigate the prevalence, antibiotic resistance, presence of class 1 and 2 integrons, Extended Spectrum β-Lactamases (ESBL) genes, phylogenetic group and epidemiological relationships of EPEC, ETEC and EHEC pathotypes isolated from patients with diarrhea and farm animals in south east region of Iran. A total of 671 diarrheagenic E. coli (DEC) were collected from stool samples of 395 patients with diarrhea and 276 farm cattles and goats. Presence of EPEC, ETEC and EHEC were identified using multiplex-PCR employing primers targeted the shiga toxin (stx), intimin (eae), bundle forming pili (bfp), and enterotoxins (lt and st) genes. The highest proportion of the patients (64%) were children under age 1–15 year (p ≤ 0.05). Among the isolates, atypical EPEC was detected in 26 patients and 14 animal stool samples, while typical EPEC was found in 2 cattles. ETEC isolates were detected in stools of 13 patients and 4 EHEC was identified in 3 goats and one cattle. The isolates were checked for susceptibility to 14 antibiotics. 50% (n = 13) of EPEC and 61.5% (n =8) of ETEC showed multi-drug resistance (MDR) profiles and one EPEC was found to be extensive drug resistant (XDR). In contrast, EHEC isolates were susceptible to the majority of antimicrobial agents. The MDR isolates were positive for blaTEM and blaCTX-M ESBL genes and carried class 1 integrons. Further study on the biofilm formation indicated that, 3 out of 4 EHEC isolates showed strong biofilm, while other pathotypes had either moderate, weak or no biofilm activity. Majority of EPEC isolates were belonged to phylogenetic group B1, all except one ETEC were classified as phylogenetic group A and two EHEC were belonged to phylogroup D, respectively. A multilocus variable tandem repeat analysis (MLVA) exhibited 22 distinct patterns. In conclusion, MLVA data showed high clonal diversity. Presence of EHEC in animal origins pose public health concern in this region. 相似文献
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株非典型羊源布鲁菌的基因分型研究 《畜牧与饲料科学》2019,40(12):108-112
[目的]探讨采用基因分型方法对非典型布鲁菌鉴定的实用性,为非典型菌株的鉴别提供参考。[方法]采用常规鉴定方法和VITEK 2.0全自动细菌鉴定分析系统对菌株进行初步鉴定,利用AMOS-PCR进行种型鉴定,应用多位点可变数目串联重复序列分析方法(MLVA)确定菌株的基因型。[结果]常规鉴定结果显示试验菌株为疑似布鲁菌;VITEK 2.0全自动细菌鉴定系统显示3株试验菌株均为布鲁菌;AMOS-PCR扩增表明试验菌株均为羊种菌,MLVA聚类分析表明试验菌株与羊种2型布鲁菌紧密地聚为一类,属东地中海基因型,并在Panel 2B中发现了新的基因型(4-4-3-7-5),命名为CN2B-45。[结论]MLVA基因分型方法对非典型布鲁菌具有极高的分辨力,是非典型布鲁菌分型鉴别的最佳策略。 相似文献
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猕猴桃溃疡病菌biovar 3群体MLVA分型技术的建立与应用 总被引：1，自引：0，他引：1
丁香假单胞菌猕猴桃致病变种生物型3(Pseudomonas syringae pv. actinidiae biovar 3,Psa3)是猕猴桃溃疡病菌的世界流行群体,但仅在中国存在复杂的遗传多样性。开发适于Psa3群体分型的MLVA(multilocus variable-number tandem-repeat analysis)技术是探索中国Psa3起源与流行学特性的基础。本研究对7个Psa3菌株进行了全基因组测序,结合已公布的86个全基因组数据,进行比较分析发现,中国Psa3至少存在7个亚群;在各亚群间存在多态性的24个串联重复序列中,其中10个可以通过琼脂糖凝胶电泳区分开且变异指数合适,据此建立了适于Psa3的MLVA技术。采用该技术对分别来自贵州和陕西的62和9个Psa3菌株进行群体分型,分型结果与全基因组分析高度一致,证明该MLVA体系分型准确。MLVA分型结果表明:贵州主产区修文县Psa3有3个MLVA群体,其中亚群4的组内分化明显,代表最早发生的群体;而亚群 1和3的结构单一,且多在新果园发现,是新传入群体。总之,本研究建立了一套可用于Psa3群体分型的MLVA技术,将有助于解析中国各猕猴桃产区Psa3群体结构,以及探索中国Psa3的起源、传播和流行学特征。 相似文献
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S. Morandi M. Brasca R. Lodi L. Brusetti C. Andrighetto A. Lombardi 《Research in veterinary science》2010,88(3):427-435
The study concerns 130 Staphylococcus aureus strains isolated from different raw-milk dairy products (122 isolates) and human samples (eight isolates). Four different typing techniques were applied: biochemical profiles (Biolog GP), restriction fragment length polymorphism of coagulase gene (coaRFLP), random amplified polymorphic DNA (RAPD) and multilocus variable number tandem repeat analysis (MLVA). Moreover multiplex-PCR was used to study the distribution of genes encoding staphylococcal enterotoxins. The results of this study reveal marked genomic and phenotypic variability among the tested S. aureus. The considered techniques were all found useful for strain typing, but, based on discriminatory power as the key parameter of the typing system, MLVA and Biolog GP were found to be the most powerful techniques. The methods showed little concordance in terms of discerning the clusters of related strains. 相似文献
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BackgroundNumerous nosocomial infections including urinary tract infection (UTI) have been reported to be linked to Pseudomonas aeruginosa (P. aeruginosa). This bacterium is one of the most common pathogen colonized in the urinary tract. The main purpose of this study was to evaluated the presence of antibiotic resistance genes and also the most frequent genotype patterns of P. aeruginosa in the patients with UTI hospitalized in different wards of hospitals.Materials and methodsIn this study, 70 strains of P. aeruginosa isolated of urine samples from the patients with UTI were assessed. The isolated strains were genotyped using Multiple-Locus Variable Number Tandem Repeat Analysis (MLVA) method. We have also analyzed the presence of TEM and SHV resistant genes in the isolates.ResultsA total of 70 P. aeruginosa strains was isolated from the UTI patients. Based on MLVA method, 61 various genotypes of P. aeruginosa were identified which grouped into two main clusters and 4 sub-clusters. Moreover, approximately 80% and 70% of isolated strains carried the TEM and SHV resistance genes, respectively.ConclusionOur findings showed that the majority of patients hospitalized in different wards of hospitals have experienced the urinary tract infection caused by P. aeruginosa. According to the genotyping results, a high diversity of the P. aeruginosa population was observed in the patients with UTI. Our results can provide a better understanding of the P. aeruginosa genotype distribution and epidemiology of infection, which can be applied as basic data for future antibiotic therapies. 相似文献
7.
Ayumi Kobayashi Sayaka Takahashi Masaaki Ono Kiyoshi Tanaka Masato Kishima Masato Akiba Ikuo Uchida 《Acta veterinaria Scandinavica》2014,56(1):31
Background
Salmonella enterica serovar Enteritidis is a zoonotic pathogen. Human infections are associated with contaminated eggs and egg products. In Japan, since 1989, the incidence of food-borne disease caused by S. Enteritidis has increased and a pandemic has occurred; however, little is known about changes that occurred before and after this pandemic event in the dominant lineage of isolates from food-producing animals. This study aimed to determine the S. Enteritidis lineages in Japan over the last few decades by using multilocus variable-number tandem repeat analysis (MLVA).Findings
MLVA was used to analyse 79 S. Enteritidis isolates collected from chickens (n = 63), cattle (n = 12), pigs (n = 2), and goats (n = 2) during 1975–2009. The S. Enteritidis isolates showed 14 different MLVA allele combinations, which were classified into two major clusters (A and C) and a minor cluster (B). All the 62 isolates in cluster A were isolated after 1988, whereas 13 of the 17 isolates belonging to cluster B and C were isolated before 1989.Conclusions
The MLVA results showed that cluster C was predominant before 1989, and isolates in cluster A disseminated since 1989 and replaced the previous dominant clone, suggesting that isolates of cluster A originated from imported S. Enteritidis infection. 相似文献8.
奶牛乳房炎金黄色葡萄球菌的分型对预防菌株在牛体之间传播、了解菌株地域性分布特点及针对性疫苗的研制均有重要的意义。本研究旨在将多位点可变数目串联重复序列分析(MLVA)法应用于国内乳房炎金葡菌的分型研究,以进行分子流行病学调查。同时,将其与16-23SrRNA基因间区分析法(RS-PCR)的分型结果比较,以评价MLVA法对乳房炎金葡菌的分型效果。作者建立MLVA方法(多重PCR体系)对27株乳房炎金葡菌进行分型,同时应用RS-PCR法进行分型。结果2种方法均可将8个地区17个牛场分离到的27株菌全部分型,分型率为100%。MLVA法将菌株分为19个型,不同牛场来源的金葡菌均属于不同型,相同牛场来源的菌株除上海和北京某牛场外均属于相同型;此方法的分型力为0.969。RS-PCR法将菌株分为10个型,其中Ⅰ、Ⅱ和Ⅴ型菌株均来源于不同地区,分型力为0.829。结果显示,MLVA分型法具有快速、操作方便和分型能力强等特点,可应用于乳房炎金葡菌的分子流行病学研究。同时,研究表明,我国不同牛场的乳房炎金葡菌具有型特异性,该结果与少数优势型金黄色葡萄球菌引起绝大多数乳房炎的报道相反。 相似文献
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Coxiella burnetii, the etiological agent of Q fever, is a globally distributed zoonotic disease. The disease was reported serologically in different animal species and humans in Egypt but the genetic information about circulating Coxiella strains is limited. The present study aimed to genetically characterize Coxiella positive samples, identified in abortive sheep, based on a 17-loci Multiple Locus Variable number tandem repeat analysis (MLVA) panel and Multispacer Sequence Typing (MST). Four MLVA types were found among six examined samples. While all three samples examined by MST were identified as novel sequence type (ST) closely related to human heart valve isolates from France, Saudi Arabia, USA and United Kingdom. This study provides the first genetic information about circulating Coxiella strains in Egypt and improves epidemiological data of Q fever in the country. 相似文献