Characterization of Mycobacterium smegmatis sigF mutant and its regulon: overexpression of SigF antagonist (MSMEG_1803) in M. smegmatis mimics sigF mutant phenotype, loss of pigmentation, and sensitivity to oxidative stress

In Mycobacterium smegmatis, sigF is widely expressed during different growth stages and plays role in adaptation to stationary phase and oxidative stress. Using a sigF deletion mutant of M. smegmatis mc2155, we demonstrate that SigF is not essential for growth of bacterium. Deletion of sigF results...

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Main Authors: Singh, Anirudh K., Dutta, Debashis, Singh, Vandana, Srivastava, Vishal, Biswas, Rajesh K., Singh, Bhupendra N.
Format: Online
Language:English
Published: John Wiley and Sons Inc. 2015
Online Access:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4694148/
id pubmed-4694148
recordtype oai_dc
spelling pubmed-46941482016-01-06 Characterization of Mycobacterium smegmatis sigF mutant and its regulon: overexpression of SigF antagonist (MSMEG_1803) in M. smegmatis mimics sigF mutant phenotype, loss of pigmentation, and sensitivity to oxidative stress Singh, Anirudh K. Dutta, Debashis Singh, Vandana Srivastava, Vishal Biswas, Rajesh K. Singh, Bhupendra N. Original Research In Mycobacterium smegmatis, sigF is widely expressed during different growth stages and plays role in adaptation to stationary phase and oxidative stress. Using a sigF deletion mutant of M. smegmatis mc2155, we demonstrate that SigF is not essential for growth of bacterium. Deletion of sigF results in loss of carotenoid pigmentation which rendered increased susceptibility to H2O2 induced oxidative stress in M. smegmatis. SigF modulates the cell surface architecture and lipid biosynthesis extending the repertoire of SigF function in this species. M. smegmatis SigF regulon included variety of genes expressed during exponential and stationary phases of growth and those responsible for oxidative stress, lipid biosynthesis, energy, and central intermediary metabolism. Furthermore, we report the identification of a SigF antagonist, an anti‐sigma factor (RsbW), which upon overexpression in M. smegmatis wild type strain produced a phenotype similar to M. smegmatis mc2155 ΔsigF strain. The SigF‐anti‐SigF interaction is duly validated using bacterial two‐hybrid and pull down assays. In addition, anti‐sigma factor antagonists, RsfA and RsfB were identified and their interactions with anti‐sigma factor were experimentally validated. Identification of these proteins will help decode regulatory circuit of this alternate sigma factor. John Wiley and Sons Inc. 2015-10-05 /pmc/articles/PMC4694148/ /pubmed/26434659 http://dx.doi.org/10.1002/mbo3.288 Text en © 2015 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution (http://creativecommons.org/licenses/by/4.0/) License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
repository_type Open Access Journal
institution_category Foreign Institution
institution US National Center for Biotechnology Information
building NCBI PubMed
collection Online Access
language English
format Online
author Singh, Anirudh K.
Dutta, Debashis
Singh, Vandana
Srivastava, Vishal
Biswas, Rajesh K.
Singh, Bhupendra N.
spellingShingle Singh, Anirudh K.
Dutta, Debashis
Singh, Vandana
Srivastava, Vishal
Biswas, Rajesh K.
Singh, Bhupendra N.
Characterization of Mycobacterium smegmatis sigF mutant and its regulon: overexpression of SigF antagonist (MSMEG_1803) in M. smegmatis mimics sigF mutant phenotype, loss of pigmentation, and sensitivity to oxidative stress
author_facet Singh, Anirudh K.
Dutta, Debashis
Singh, Vandana
Srivastava, Vishal
Biswas, Rajesh K.
Singh, Bhupendra N.
author_sort Singh, Anirudh K.
title Characterization of Mycobacterium smegmatis sigF mutant and its regulon: overexpression of SigF antagonist (MSMEG_1803) in M. smegmatis mimics sigF mutant phenotype, loss of pigmentation, and sensitivity to oxidative stress
title_short Characterization of Mycobacterium smegmatis sigF mutant and its regulon: overexpression of SigF antagonist (MSMEG_1803) in M. smegmatis mimics sigF mutant phenotype, loss of pigmentation, and sensitivity to oxidative stress
title_full Characterization of Mycobacterium smegmatis sigF mutant and its regulon: overexpression of SigF antagonist (MSMEG_1803) in M. smegmatis mimics sigF mutant phenotype, loss of pigmentation, and sensitivity to oxidative stress
title_fullStr Characterization of Mycobacterium smegmatis sigF mutant and its regulon: overexpression of SigF antagonist (MSMEG_1803) in M. smegmatis mimics sigF mutant phenotype, loss of pigmentation, and sensitivity to oxidative stress
title_full_unstemmed Characterization of Mycobacterium smegmatis sigF mutant and its regulon: overexpression of SigF antagonist (MSMEG_1803) in M. smegmatis mimics sigF mutant phenotype, loss of pigmentation, and sensitivity to oxidative stress
title_sort characterization of mycobacterium smegmatis sigf mutant and its regulon: overexpression of sigf antagonist (msmeg_1803) in m. smegmatis mimics sigf mutant phenotype, loss of pigmentation, and sensitivity to oxidative stress
description In Mycobacterium smegmatis, sigF is widely expressed during different growth stages and plays role in adaptation to stationary phase and oxidative stress. Using a sigF deletion mutant of M. smegmatis mc2155, we demonstrate that SigF is not essential for growth of bacterium. Deletion of sigF results in loss of carotenoid pigmentation which rendered increased susceptibility to H2O2 induced oxidative stress in M. smegmatis. SigF modulates the cell surface architecture and lipid biosynthesis extending the repertoire of SigF function in this species. M. smegmatis SigF regulon included variety of genes expressed during exponential and stationary phases of growth and those responsible for oxidative stress, lipid biosynthesis, energy, and central intermediary metabolism. Furthermore, we report the identification of a SigF antagonist, an anti‐sigma factor (RsbW), which upon overexpression in M. smegmatis wild type strain produced a phenotype similar to M. smegmatis mc2155 ΔsigF strain. The SigF‐anti‐SigF interaction is duly validated using bacterial two‐hybrid and pull down assays. In addition, anti‐sigma factor antagonists, RsfA and RsfB were identified and their interactions with anti‐sigma factor were experimentally validated. Identification of these proteins will help decode regulatory circuit of this alternate sigma factor.
publisher John Wiley and Sons Inc.
publishDate 2015
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4694148/
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