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沙门氏菌的致病性 岛屿1在适应猪和家禽的血清体中发生衰变
Martina Tambassi1, Melissa Berni1, Chiara Bracchi1
1Risk Analysis and Genomic Epidemiology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna (IZSLER), Parma, Italy.
Microbiology spectrum
|December 11, 2024
概括
适应畜牧业的沙门氏菌血清病毒,如S. Derby和S. Rissen,显示SPI-1突变增加,SPI-1是关键的毒性因子,导致衰减. 这表明食物传播病原体的毒性减少的趋同进化,可能是由密集农业实践驱动的.
科学领域:
- 微生物学 微生物学
- 食品安全 食品安全
- 进化生物学 进化生物学
背景情况:
- 人类沙门氏菌病是全球重要的食物传播疾病,主要源于猪和家禽等牲畜库.
- 适应牲畜的沙门氏菌血清病毒在宿主和人类中经常减弱,这种现象以前与沙门氏菌致病性岛-1 (SPI-1) 的突变有关.
研究的目的:
- 调查SPI-1的衰变是否是猪适应的沙门氏菌血清菌种中常见的进化特征.
- 评估SPI-1中各种适应牲畜的沙门氏菌血清体的有害突变在人口水平上的积累.
主要方法:
- 对从猪中频繁分离的沙门氏菌血清体的Enterobase全球人口数据的分析.
- 进行比较基因组分析,以识别和量化猪适应型 (S. Derby,S. Rissen) 和通用型 (S. Typhimurium,I 1,4,[5],12:i:-,S. Infantis) 血清病毒中SPI-1的有害突变.
- 包括适应家禽的南肯塔基州及其通用主义对应物,以获得更广泛的进化视角.
主要成果:
- 与一般性血清病毒相比,猪适应的血清病毒S.Derby和S.Rissen的有害SPI-1突变积累明显更高.
- 突变的SPI-1基因组在S. Derby和S. Rissen种群中普遍存在,这表明突变发生和固定频繁.
- 适应家禽的S.肯塔基也显示了大量的SPI-1突变积累 (超过70%的突变基因组),与一般家禽血清病毒形成鲜明对比.
结论:
- 种群规模数据提供了通过SPI-1衰变向动物适应的沙门氏菌血清体减弱的趋同演变的证据.
- 具有高动物密度的密集农业实践可能是推动这种进化趋势的促成因素.
- 这些发现支持在食品安全立法中重新评估微生物学标准,考虑到不同沙门氏菌系的不同毒力.
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