致病潜力和抗生素敏感性:来自不同生态环境的菌的全面研究
Maria Pandova1, Yoana Kizheva1, Margarita Tsenova1
1Department of General and Industrial Microbiology, Faculty of Biology, Sofia University, 1164 Sofia, Bulgaria.
Pathogens (Basel, Switzerland)
|January 22, 2024
概括
这项研究调查了来自各种食物和动物来源的肠球菌的致病性. 虽然许多菌株表现出抗生素耐药性,但很少有人同时表现出血解和凝酶活性等关键毒性因素.
科学领域:
- 微生物学 微生物学
- 食品科学 食品科学 食品科学
- 公共卫生 公共卫生
背景情况:
- 菌种类居住在各种环境中,包括食品和动物肠道.
- 肠球菌的致病性和生活方式是复杂的,需要详细的研究.
- 了解肠球菌的毒性和耐药性对于食品安全和人类健康至关重要.
研究的目的:
- 为了追踪从七个不同的息地中分离出的肠球菌的致病性.
- 为了比较来自食品,动物和人类来源的肠球菌株的致病潜力.
- 在孤立的肠球菌中识别毒性因素和抗生素耐药性概况.
主要方法:
- 使用MALDI-TOF,测序和PCR.分离和识别了72种肠球菌菌株.
- 血液溶解和凝酶活性的生物化学确定.
- 病毒性基因 (例如cylB,esp,gelE) 和抗生素耐药性基因 (例如erm,vanA,gyrA) 的PCR检测.
- 根据EUCAST指南进行表型抗生素耐药性评估.
主要成果:
- 鉴定了11个Enterococcus物种,具有不同的血液溶解和凝酶活性.
- 只有13个菌株拥有cylB基因,只有两个菌株同时表现出alpha-hemolysis和cylB存在.
- 虽然 35% 的分离物具有 gelE 基因,但只有三种表现出类型的凝酶活性.
- 所有分离物体都表现出抗生素耐药性;一个E. faecalis菌株表现出多重耐药性.
- 在两个E. faecalis菌株中观察到基因型和表型宏类耐药性之间的相关性.
结论:
- 肠球菌的致病性是特定于菌株和取决于息地.
- 病毒性基因的存在并不总是与表型表达相关.
- 抗生素耐药性普遍存在,突出显示需要监测和控制策略.
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