Distribution of Genes for Synthesis of Trehalose and Mannosylglycerate in Thermus spp. and Direct Correlation of These Genes with Halotolerance

• Published in: Applied and Environmental Microbiology Vol. 71; no. 5; pp. 2460 - 2466
• Main Authors: Alarico, Susana, Empadinhas, Nuno, Simões, Catarina, Silva, Zélia, Henne, Anke, Mingote, Ana, Santos, Helena, da Costa, Milton S
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for Microbiology 01-05-2005
• Subjects: Bacteria; Bacteriology; Base Sequence; Biological and medical sciences; Biology of microorganisms of confirmed or potential industrial interest; Biotechnology; carbohydrate metabolism; Fundamental and applied biological sciences. Psychology; Genes; Genetics; Glyceric Acids; Mannose - analogs & derivatives; Mannose - biosynthesis; Microbiology; Mission oriented research; Molecular Sequence Data; osmoregulation; Osmosis; Physiology and Biotechnology; Salt; salt tolerance; sodium chloride; Sodium Chloride - pharmacology; strains; Sugar; Thermus; Thermus - drug effects; Thermus - growth & development; Thermus - metabolism; Thermus thermophilus; trehalose; Trehalose - biosynthesis; Halotolerance; Correlation; Thermus; Gene; Trehalose; Bacteria; Biosynthesis
• ISSN: 0099-2240; 1098-5336
• DOI: 10.1128/AEM.71.5.2460-2466.2005

In this study we correlate the presence of genes leading to the synthesis of trehalose and mannosylglycerate (MG) in 17 strains of the genus Thermus with the ability of the strains to grow and accumulate these compatible solutes in a defined medium containing NaCl. The two sets of genes, namely, otsA/otsB for the synthesis of trehalose and mpgS/mpgP for the synthesis of MG, were necessary for the growth of Thermus thermophilus in a defined medium containing up to 6% NaCl. Strains lacking a complete otsA gene did not grow in defined medium containing >2% NaCl. One strain of T. thermophilus lacking the genes for the synthesis of MG did not grow in a medium with >1% NaCl. We did not identify any of these genes in the type strains of the other seven species of Thermus, and none of those strains grew in defined medium with 1% NaCl. The results strongly indicate that the combined accumulation of trehalose and MG is required for optimal osmotic adjustment.