Abstract:
:High concentrations of free metal ions in the environment can be detrimental to bacterial survival. However, bacteria utilize strategies, including the activation of stress response pathways and immobilizing chemical elements on their surface, to limit this toxicity. In this study, we characterized LA4131, the HtpX-like M48 metalloprotease from Leptospira interrogans, with a putative role in bacterial stress response and membrane homeostasis. Growth of the la4131 transposon mutant strain (L522) in 360 μM FeSO4 (10-fold the normal in vitro concentration) resulted in the production of an amorphous iron precipitate. Atomic force microscopy and transmission electron microscopy analysis of the strain demonstrated that precipitate production was associated with the generation and release of outer membrane vesicles (OMVs) from the leptospiral surface. Transcriptional studies indicated that inactivation of la4131 resulted in altered expression of a subset of metal toxicity and stress response genes. Combining these findings, this report describes OMV production in response to environmental stressors and associates OMV production with the in vitro activity of an HtpX-like metalloprotease.
journal_name
Appl Environ Microbioljournal_title
Applied and environmental microbiologyauthors
Henry R,Lo M,Khoo C,Zhang H,Boysen RI,Picardeau M,Murray GL,Bulach DM,Adler Bdoi
10.1128/AEM.01097-13subject
Has Abstractpub_date
2013-08-01 00:00:00pages
4653-60issue
15eissn
0099-2240issn
1098-5336pii
AEM.01097-13journal_volume
79pub_type
杂志文章abstract::Because of high diurnal water quality fluctuations in raw municipal wastewater, the use of proportional autosampling over a period of 24 h at municipal wastewater treatment plants (WWTPs) to evaluate carbon, nitrogen, and phosphorus removal has become a standard in many countries. Microbial removal or load estimation ...
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doi:10.1128/AEM.57.11.3150-3155.1991
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
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journal_title:Applied and environmental microbiology
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
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