Unknown,Transcriptomics,Genomics,Proteomics

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Global profiling of B. subtilis comparing wild-type to mutants with altered cytoplasmic membrane composition

ABSTRACT: The Bacillus subtilis membrane contains diacylglycerol-based lipids with at least five distinct headgroups that impart distinct physical and chemical properties to the lipid bilayer. Here, we describe the phenotypic characterization of mutant strains lacking one or more of the following lipids: glycolipids (ugtP mutants), phosphatidylethanolamine (pssA and psd mutants), lysylphosphatidylglycerol (mprF), and cardiolipin (ywnE and ywjE). Alterations of membrane lipid headgroup composition are generally well tolerated by the cell and even severe alterations lead to only modest effects on growth proficiency. Mutants with decreased levels of positively charged lipids display an increased sensitivity to a cationic antimicrobial compounds and cells lacking glycolipids are sensitive to the lantibiotic sublancin and are defective in swarming motility. A quadruple mutant strain (ugtP pssA mprF ywnE), with a membrane comprised predominantly of phosphatidylglycerol, is viable and grows at near wild-type rates, although it forms long, coiled filaments. Transcriptome comparisons identify numerous regulons with altered expression in ugtP mutant cells, the pssA mprF ywnE triple mutant, and the uptP pssA mprF ywnE quadruple mutant. These effects include a general decrease in expression of the SigD and FapR regulons, and increased expression of cell envelope stress responses mediated by ?M and the YvrGHb two-component system. WT vs.ugtP single mutant (U), WT vs. mprFpssAywnE triple mutant (T) or WT vs. ugtPmprFpssAywnE quadruple mutant (Q). Each experiment (WT vs. mutant) was conducted four times using three independent total RNA preparations (3 independent experiement + dye swap). For the 3 datasets used for final analysis wild-type was labeled with Alexa Fluor 555 and mutants with Alexa Fluor 647. For dye swap experiments wild-type was labeled with Alexa Fluor 647 and mutants with Alexa Fluor 555.

ORGANISM(S): Bacillus subtilis

SUBMITTER: Letal Salzberg

PROVIDER: E-GEOD-13036 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Phenotypic and transcriptomic characterization of Bacillus subtilis mutants with grossly altered membrane composition.

Salzberg Letal I LI Helmann John D JD

Journal of bacteriology 20080926 23

The Bacillus subtilis membrane contains diacylglycerol-based lipids with at least five distinct headgroups that together help to define the physical and chemical properties of the lipid bilayer. Here, we describe the phenotypic characterization of mutant strains lacking one or more of the following lipids: glycolipids (ugtP mutants), phosphatidylethanolamine (pssA and psd mutants), lysylphosphatidylglycerol (mprF), and cardiolipin (ywnE and ywjE). Alterations of membrane lipid headgroup composit ...[more]

PMID: 18820022

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Dataset Information

Global profiling of B. subtilis comparing wild-type to mutants with altered cytoplasmic membrane composition

Publications

Phenotypic and transcriptomic characterization of Bacillus subtilis mutants with grossly altered membrane composition.

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