鲍曼不动杆菌在微生物混合物中的生存能力和毒力。

Survival and virulence of Acinetobacter baumannii in microbial mixtures.

机构信息

Biotechnology Laboratory, Environmental Health Science and Research Bureau, Environmental and Radiation Health Sciences Directorate, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, ON, K1A 0K9, Canada.

Scientific Services Division, Bureau of Chemical Safety, Food Directorate, Health Products and Food Branch, Health Canada, Ottawa, ON, K1A 0K9, Canada.

出版信息

BMC Microbiol. 2024 Sep 6;24(1):324. doi: 10.1186/s12866-024-03471-6.

DOI:10.1186/s12866-024-03471-6

PMID:39243004

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11378493/

Abstract

Acinetobacter species such as A. venetianus and A. guillouiae have been studied for various biotechnology applications, including bioremediation of recalcitrant and harmful environmental contaminants, as well as bioengineering of enzymes and diagnostic materials. Bacteria used in biotechnology are often combined with other microorganisms in mixtures to formulate efficacious commercial products. However, if the mixture contained a closely related Acinetobacter pathogen such as A. baumannii (Ab), it remains unclear whether the survival and virulence of Ab would be masked or augmented. This uncertainty poses a challenge in ensuring the safety of such biotechnology products, since Ab is one of the most significant pathogens for both hospital and community -acquired infections. This research aimed to investigate the growth and virulence of Ab within a mixture of 11 bacterial species formulated as a mock microbial mixture (MM). Growth challenges with environmental stressors (i.e., temperature, pH, sodium, iron, and antibiotics) revealed that Ab could thrive under diverse conditions except in the presence of ciprofloxacin. When cultured alone, Ab exhibited significantly more growth in the presence of almost all the environmental stressors than when it was co-incubated with the MM. During the exposure of A549 lung epithelial cells to the MM, Ab growth was stimulated compared to that in standard mammalian culture media. Cytotoxicity caused by Ab was suppressed in the presence of the MM. Lymphocytes were significantly reduced in mice exposed to Ab with or without MM via intravenous injection. The levels of the splenic cytokines IL-1α, IL-1β, MCP-1, and MIP-1α were significantly reduced 24 h after exposure to Ab + MM. This study demonstrated that the presence of the MM marginally but significantly reduced the growth and virulence of Ab, which has implications for the safety of mixtures of microorganisms for biotechnological applications. Furthermore, these findings expand our understanding of the virulence of Ab during host-pathogen interactions.

摘要

不动杆菌属物种，如威尼斯不动杆菌和吉劳氏不动杆菌，已被研究用于各种生物技术应用，包括难处理和有害环境污染物的生物修复，以及酶和诊断材料的生物工程。用于生物技术的细菌通常与其他微生物混合在一起，以配制有效的商业产品。然而，如果混合物中含有一种密切相关的不动杆菌病原体，如鲍曼不动杆菌（Ab），那么 Ab 的生存和毒力是否会被掩盖或增强仍不清楚。这种不确定性给此类生物技术产品的安全性带来了挑战，因为 Ab 是医院和社区获得性感染的最重要病原体之一。本研究旨在调查 Ab 在模拟微生物混合物（MM）中与 11 种细菌混合生长和毒力。用环境胁迫物（即温度、pH 值、钠、铁和抗生素）进行生长挑战，结果表明，Ab 可以在多种条件下茁壮成长，除了在环丙沙星存在的情况下。当单独培养时，Ab 在存在几乎所有环境胁迫物的情况下比与 MM 共同孵育时生长得更多。当 A549 肺上皮细胞暴露于 MM 时，与标准哺乳动物培养基相比，Ab 的生长受到刺激。在 MM 存在的情况下，Ab 引起的细胞毒性受到抑制。通过静脉注射将 Ab 暴露于 MM 的小鼠的淋巴细胞明显减少。暴露于 Ab 加 MM 的小鼠的脾脏细胞因子 IL-1α、IL-1β、MCP-1 和 MIP-1α 的水平在 24 小时后显著降低。这项研究表明，MM 的存在略微但显著降低了 Ab 的生长和毒力，这对生物技术应用中微生物混合物的安全性有影响。此外，这些发现扩展了我们对 Ab 在宿主-病原体相互作用期间毒力的理解。