Distribution of compatible solutes in the halophilic methanogenic archaebacteria

Journal Article · Sun Sep 01 00:00:00 EDT 1991 · Journal of Bacteriology; (United States)

OSTI ID:5755338

Lai, Meichin; Sowers, K R; Gunsalus, R P ^[1]; Robertson, D E; Roberts, M F ^[2]

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1. Univ. of California, Los Angeles (United States)
2. Boston College, Chestnut Hill, MA (United States)

Accumulation of compatible solutes, by uptake or de novo synthesis, enables bacteria to reduce the difference between osmotic potentials of the cell cytoplasm and the extracellular environment. To examine this process in the halophilic and halotolerant methanogenic archaebacteria, 14 strains were tested for the accumulation of compatible solutes in response to growth in various extracellular concentrations of NaCl. In external NaCl concentrations of 0.7 to 3.4 M, the halophilic methanogens accumulated K{sup +} ion and low-molecular-weight organic compounds. {beta}-Glutamate was detected in two halotolerant strains that grew below 1.5 M NaCl. Two unusual {beta}-amino acids, N{sub {var epsilon}}-acetyl-{beta}-lysine and {beta}-glutamine (3-aminoglutaramic acid), as well as L-{alpha}-glutamate were compatible solutes among all of these strains. De novo synthesis of glycine betaine was also detected in several strains of moderately and extremely halophilic methanogens. The zwitterionic compounds ({beta}-glutamine, N{sub {var epsilon}}-acetyl-{beta}-lysine,a nd glycine betaine) and potassium were the predominant compatible solutes among the moderately and extremely halophilic methanogens. This is the first report of {beta}-glutamine as a compatible solute and de novo biosynthesis of glycine betaine in the methanogenic archaebacteria.

• DOE Contract Number: FG03-86ER13498
• OSTI ID: 5755338
• Journal Information: Journal of Bacteriology; (United States), Vol. 173:17; ISSN 0021-9193
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
METHANOGENIC BACTERIA
PHYSIOLOGY
SODIUM CHLORIDES
BIOLOGICAL ADAPTATION
AMINO ACIDS
BETAINE
TOLERANCE
ALKALI METAL COMPOUNDS
AMINES
AMMONIUM COMPOUNDS
BACTERIA
CARBOXYLIC ACIDS
CHLORIDES
CHLORINE COMPOUNDS
DRUGS
HALIDES
HALOGEN COMPOUNDS
LIPOTROPIC FACTORS
MICROORGANISMS
ORGANIC ACIDS
ORGANIC COMPOUNDS
QUATERNARY COMPOUNDS
SODIUM COMPOUNDS
550200* - Biochemistry