AEM
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Robertson, D E
Right arrow Articles by Boone, D R
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Robertson, D E
Right arrow Articles by Boone, D R
Agricola
Right arrow Articles by Robertson, D E
Right arrow Articles by Boone, D R

 Previous Article

Appl Environ Microbiol. 1990 May; 56(5): 1504-1508

Occurrence of beta-glutamate, a novel osmolyte, in marine methanogenic bacteria.

D E Robertson, M F Roberts, N Belay, K O Stetter and D R Boone

Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02167.

ABSTRACT

The unusual compound beta-aminoglutaric acid (beta-glutamate) has been identified by 13C nuclear magnetic resonance spectroscopy in soluble extracts of marine methanogenic bacteria. We examined several methanogen species representing nine genera and found that beta-glutamate occurred in methanococci and two methanogenium strains (Methanogenium cariaci JR1 and "Methanogenium anulus" AN9). The presence of this compound in the methanococci examined was further restricted to thermophilic members of the genus Methanococcus, including Methanococcus thermolithotrophicus strains, Methanococcus jannaschii, and "Methanococcus igneus." The two Methanogenium strains examined were mesophiles. Studies using Methanococcus thermolithotrophicus showed that levels of beta-glutamate in cells of that species were not affected by variation in growth temperature (40 to 65 degrees C), NH4+ (2 to 80 mM), Mg2+ (10 to 50 mM), or K+ (2 to 10 mM) in the medium. In contrast, soluble pools of beta-glutamate and L-alpha-glutamate (the other major free amino acid in all the methanococci) were proportional to NaCl levels in the growth medium. This dependence of beta-glutamate and L-alpha-glutamate concentrations on salt levels in the medium suggests that they function as osmolytes in these cells.

Appl Environ Microbiol. 1990 May; 56(5): 1504-1508




This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. Microbiol. Mol. Biol. Rev. Eukaryot. Cell All ASM Journals

Copyright © 1990 by the American Society for Microbiology. All rights reserved.