Molecular typing of Salmonella enterica serovar Typhimurium

鼠伤寒肠沙门氏菌血清型的分子分型

• 批准号: nhmrc : 153941
• 负责人: A/Pr Ruiting Lan
• 金额: $ 18.17万
• 依托单位国家: 澳大利亚
• 项目类别: NHMRC Project Grants
• 财政年份: 2001
• 资助国家: 澳大利亚
• 起止时间: 2001-01-01 至 2003-12-31
• 项目状态: 已结题
• 来源: https://researchdata.edu.au/molecular-typing-salmonella-serovar-typhimurium/94386
• 关键词: Molecular; typing; Salmonella; enterica; serovar

Salmonella mainly causes food poisoning and is a significant human health problem. Different Samonella forms are identified by serotyping and many serovars have been given a name . There are more than 2000 serovars. The best known serovar is Typhimurium which is the cause of 40% of salmonella infections. Typhimurium is so frequently involved in infections it is necessary to further divide it for outbreak investigations and long term monitoring of the organism. The only widely used method to subdivide Typhimurium is phage typing, which is done only in major laboratories (2 in Australia). Phage typing is based on lysis patterns of a test isolate to a set of 34 phages. Phage typing has played a crucial role in tracking the organism, for example the emergence of a multidrug resistance new type (DT204c) in UK and US. The technique is simple but the problem is that reactions vary with slight change in conditions and scoring the reaction results is very subjective. We propose to replace the typing system with one based on the DNA method PCR, so it will be simple, fast and accurate. We will use a DNA fingerprinting technique called AFLP (amplified fragment length polymorphism) to find markers (DNA segments) that are specific to phage types and design PCR assays based on the markers we find. Such a typing system will retain the essence of phage typing by providing continuity of the valuable epidemiological database on phage types. Further the typing system could easily be expanded to accommodate any new types by finding more markers while the current phage typing system is very difficult to expand (last done in 1977 and is behind in our needs). This project will establish a general approach for designing typing systems based on molecular biology for other pathogens and could have a major impact on the surveillance of bacterial infections in the 21st century.

沙门氏菌主要引起食物中毒，是一个严重的人类健康问题。不同的沙门氏菌形式通过血清分型进行鉴定，并且许多血清型已被命名。有超过2000个血清型。最著名的血清型是鼠伤寒杆菌，它是 40% 沙门氏菌感染的原因。鼠伤寒菌经常引起感染，因此有必要对其进行进一步分类，以便进行暴发调查和对该生物体的长期监测。唯一广泛使用的鼠伤寒杆菌细分方法是噬菌体分型，该方法仅在主要实验室进行（澳大利亚有 2 个实验室）。噬菌体分型基于测试分离株对一组 34 个噬菌体的裂解模式。噬菌体分型在追踪生物体方面发挥了至关重要的作用，例如英国和美国出现的多重耐药新型（DT204c）。该技术很简单，但问题是反应会随着条件的轻微变化而变化，并且对反应结果的评分非常主观。我们建议用基于 DNA 方法 PCR 的分型系统取代分型系统，这样会简单、快速、准确。我们将使用称为 AFLP（扩增片段长度多态性）的 DNA 指纹技术来查找特定于噬菌体类型的标记（DNA 片段），并根据我们找到的标记设计 PCR 测定。这样的分型系统将通过提供关于噬菌体类型的有价值的流行病学数据库的连续性来保留噬菌体分型的本质。此外，通过寻找更多标记，分型系统可以轻松扩展以适应任何新类型，而当前的噬菌体分型系统很难扩展（上次完成于 1977 年，落后于我们的需求）。该项目将建立一种基于分子生物学的其他病原体分型系统设计的通用方法，并可能对 21 世纪细菌感染的监测产生重大影响。