Journal article
The Sinorhizobium medicae WSM419 lpiA gene is transcriptionally activated by FsrR and required to enhance survival in lethal acid conditions
Microbiology, Vol.152(10), pp.3049-3059
2006
Abstract
Sinorhizobium medicae WR101 was identified as a mutant of WSM419 that contained a minitransposon-induced transcriptional gusA fusion activated at least 20-fold at pH 5-7. The expression of this fusion in moderately acid conditions was dependent on the calcium concentration; increasing the calcium concentration to enhance cell growth and survival in acid conditions decreased the expression of the fusion. A gene region containing the gusA fusion was sequenced, revealing five S medicae genes: tcsA, tcrA, fsrR, lpiA and acvB. The gusA reporter in WRI101 was fused to lpiA, which encodes a putative transmembrane protein also found in other Alphaproteobacteria such as Sinorhizobium metiloti, Rhizobium tropici and Agrobacterium tumetaciens. As LpiA has partial sequence similarity to the lysyl-phosphatidylglycerol (LPG) synthetase FmtC/MprF from Staphylococcus aureus, membrane lipid compositions of S. medicae strains were analysed. Cells cultured under neutral or acidic growth conditions did not induce any detectable LPG and therefore this lipid cannot be a major constituent of S. medicae membranes. Expression studies in S. medicae localized the acid-activated IpiA promoter within a 372 bp region upstream of the start codon. The acid-activated transcription of 1piA required the fused sensor-regulator product of the fsrR gene, because expression of lpiA was severely reduced in an S. medicae fsrR mutant. S. meliloti strain 1021 does not contain fsrR and acid-activated expression of the lpiA-gusA fusion did not occur in this species. Although acid-activated 1piA transcription was not required for cell growth, its expression was crucial in enhancing the viability of cells subsequently exposed to lethal acid (pH 4.5) conditions.
Details
- Title
- The Sinorhizobium medicae WSM419 lpiA gene is transcriptionally activated by FsrR and required to enhance survival in lethal acid conditions
- Authors/Creators
- W.G. Reeve (Author/Creator) - Murdoch UniversityL. Bräu (Author/Creator) - Murdoch UniversityJ.M. Castelli (Author/Creator) - The University of Western AustraliaG. Garau (Author/Creator) - University of SassariC. Sohlenkamp (Author/Creator) - Universidad Nacional Autónoma de MéxicoO. Geiger (Author/Creator) - Universidad Nacional Autónoma de MéxicoM.J. Dilworth (Author/Creator) - Murdoch UniversityA.R. Glenn (Author/Creator) - University of TasmaniaJ.G. Howieson (Author/Creator) - Murdoch UniversityR.P. Tiwari (Author/Creator) - Murdoch University
- Publication Details
- Microbiology, Vol.152(10), pp.3049-3059
- Publisher
- Society for General Microbiology
- Identifiers
- 991005542669807891
- Copyright
- © 2006 SGM
- Murdoch Affiliation
- Centre for Rhizobium Studies
- Language
- English
- Resource Type
- Journal article
UN Sustainable Development Goals (SDGs)
This output has contributed to the advancement of the following goals:
Source: InCites
Metrics
94 Record Views
InCites Highlights
These are selected metrics from InCites Benchmarking & Analytics tool, related to this output
- Collaboration types
- Domestic collaboration
- International collaboration
- Citation topics
- 3 Agriculture, Environment & Ecology
- 3.97 Plant Pathology
- 3.97.892 Rhizobium-Legume Symbiosis
- Web Of Science research areas
- Microbiology
- ESI research areas
- Microbiology