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 Harris, M. A.
Right arrow Articles by Reddy, C. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Harris, M. A.
Right arrow Articles by Reddy, C. A.

 Previous Article  |  Next Article 

J Bacteriol. 1977 September; 131(3): 922-928
Copyright © 1977 American Society for Microbiology. All Rights Reserved.

Hydrogenase Activity and the H2-Fumarate Electron Transport System in Bacteroides fragilis1

Martha A. Harris and C. Adinaryayana Reddy

Department of Microbiology and Public Health, Michigan State University, East Lansing, Michigan 48824

ABSTRACT

Hydrogenase activity and the H2-fumarate electron transport system in a carbohydrate-fermenting obligate anaerobe, Bacteroides fragilis, were investigated. In both whole cells and cell extracts, hydrogenase activity was demonstrated with methylene blue, benzyl viologen, flavin mononucleotide, or flavin adenine dinucleotide as the electron acceptor. A catalytic quantity of benzyl viologen or ferredoxin from Clostridium pasteurianum was required to reduce nicotinamide adenine dinucleotide or nicotinamide adenine dinucleotide phosphate with H2. Much of the hydrogenase activity appeared to be associated with the soluble fraction of the cell. Fumarate reduction to succinate by H2 was demonstrable in cell extracts only in the presence of a catalytic quantity of benzyl viologen, flavin mononucleotide, flavin adenine dinucleotide, or ferredoxin from C. pasteurianum. Sulfhydryl compounds were not required for fumarate reduction by H2, but mercaptoethanol and dithiothreitol appeared to stimulate this activity by 59 and 61%, respectively. Inhibition of fumarate reduction by acriflavin, rotenone, 2-heptyl-4-hydroxyquinoline-N-oxide, and antimycin A suggest the involvement of a flavoprotein, a quinone, and cytochrome b in the reduction of fumarate to succinate. The involvement of a quinone in fumarate reduction is also apparent from the inhibition of fumarate reduction by H2 when cell extracts were irradiated with ultraviolet light. Based on the evidence obtained, a possible scheme for the flow of electrons from H2 to fumarate in B. fragilis is proposed.

FOOTNOTES

1 Journal article 7914, Michigan Agricultural Experiment Station.

J Bacteriol. 1977 September; 131(3): 922-928
Copyright © 1977 American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Baughn, A. D., Malamy, M. H. (2003). The essential role of fumarate reductase in haem-dependent growth stimulation of Bacteroides fragilis. Microbiology 149: 1551-1558 [Abstract] [Full Text]  
  • Baughn, A. D., Malamy, M. H. (2002). From the Cover: A mitochondrial-like aconitase in the bacterium Bacteroides fragilis: Implications for the evolution of the mitochondrial Krebs cycle. Proc. Natl. Acad. Sci. USA 99: 4662-4667 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»