title: Distribution of genes for synthesis of trehalose and Mannosylglycerate in Thermus spp. and direct correlation of these genes with halotolerance.
abstract: 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.
authors.affiliation: Departamento de Bioquímica, Centro de Neurociências e Biologia Celular, Universidade de Coimbra, 3004-517 Coimbra, Portugal.
authors.forename: Susana
authors.initials: S
authors.lastname: Alarico
authors.forename: Nuno
authors.initials: N
authors.lastname: Empadinhas
authors.forename: Catarina
authors.initials: C
authors.lastname: Simões
authors.forename: Zélia
authors.initials: Z
authors.lastname: Silva
authors.forename: Anke
authors.initials: A
authors.lastname: Henne
authors.forename: Ana
authors.initials: A
authors.lastname: Mingote
authors.forename: Helena
authors.initials: H
authors.lastname: Santos
authors.forename: Milton S
authors.initials: MS
authors.lastname: da Costa
mesh_terms: D001483:Base Sequence; D005988:Glyceric Acids; D008358:Mannose / Q000031:analogs & derivatives* / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D012965:Sodium Chloride / Q000494:pharmacology; D013824:Thermus / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D014199:Trehalose / Q000096:biosynthesis*
chemical_list: D005988:Glyceric Acids; C402688:mannosylglycerate; D012965:Sodium Chloride; D014199:Trehalose; D008358:Mannose