A prominent role for glucosylglycerol in the adaptation of Pseudomonas mendocina SKB70 to osmotic stress.

AUTOR(ES)

Pocard, J A

RESUMO

The mechanism of osmoadaptation in a salt-tolerant (1.2 M NaCl) bacterial isolate identified as Pseudomonas mendocina (N. J. Palleroni, M. Doudoroff, R. Y. Stanier, R. E. Solanes, and R. Mandel, J. Gen. Microbiol. 60:215-231, 1970) was investigated. In response to osmotic stress, this species accumulated a number of compatible solutes, the intracellular levels of which depended on both the osmolarity and the ionic composition of the growth medium. Glucosylglycerol [alpha-D-glucopyranosyl-alpha-(1-->2)-glycerol], N-acetylglutaminylglutamine amide, and L-alpha-glutamate were the major compatible solutes accumulated via de novo biosynthesis. Trehalose was also accumulated, but only in cells grown in the presence of high concentrations of sulfate or phosphate ions. Glycine betaine was accumulated only when supplied exogenously to cells grown at high osmolarity, and its accumulation caused a significant depletion of the intracellular pools of glucosylglycerol and glutamate. Glucosylglycerol was also found to accumulate in the type strains of P. mendocina and P. pseudoalcaligenes. This is the first report demonstrating the pivotal role of glucosylglycerol in osmoadaptation in a nonphotosynthetic microorganism.

Documentos Relacionados

• Roles of N-acetylglutaminylglutamine amide and glycine betaine in adaptation of Pseudomonas aeruginosa to osmotic stress.
• Role of manganese superoxide dismutase in a mucoid isolate of Pseudomonas aeruginosa: adaptation to oxidative stress.
• Adaptation during surgical stress. A reevaluation of the role of glucocorticoids.
• Physiological and genetic responses of bacteria to osmotic stress.
• Accumulation of glutamate by Salmonella typhimurium in response to osmotic stress.