Survival and exopolysaccharide production in Sinorhizobium meliloti WSM419 are affected by calcium and low pH
Article Abstract:
Research was conducted to determine whether the growth-accelerating effect of calcium at pH values allowing growth extended to an enhancement of the survival of Sinorhizobium meliloti WSM419 during exposure to much more acid conditions that do not permit growth. A further objective was to determine if any such protection was connected to the quantity or quality of epopolysaccharide (EPS) produced. Results suggest that calcium protects cells from acid-induced death and does not affect the type of EPS generated at low pH.
Publication Name: Microbiology
Subject: Biological sciences
ISSN: 1350-0872
Year: 1999
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The transcriptional regulator gene phrR in Sinorhizobium meliloti WSM419 is regulated by low pH and other stresses
Article Abstract:
A pH-regulated (phrR) gene was discovered in the Sinorhizobium meliloti WSM491, formerly known as Rhizobium meliloti, located downstream from the lipid acyl transferase (actA) gene. The organism was observed to be more tolerant against acid soils than other forms of the strains. It was indicated that the actA gene of the organism was required for acid tolerance and growth at low pH. The phrR gene encoded a putative repressor protein, PhrR, induced by low pH and other forms of environmental stresses.
Publication Name: Microbiology
Subject: Biological sciences
ISSN: 1350-0872
Year: 1998
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Constructs for insertional mutagenesis, transcriptional signal localization and gene regulation studies in root nodule and other bacteria
Article Abstract:
A study was conducted to analyze alternative minitransposons that may be utilized to complement Tn5 derivatives. The number of restriction sites in the mTn5s was significantly minimize to increase the range of endonucleases which can be used to cut mutated target DNA in preparation for cloning. Results indicated novel constructs that provide useful tools for insertional mutagenesis, transcriptional signal localization and gene regulation studies.
Publication Name: Microbiology
Subject: Biological sciences
ISSN: 1350-0872
Year: 1999
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