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 Boone, D. R.
Right arrow Articles by Liu, Y.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Boone, D. R.
Right arrow Articles by Liu, Y.
Agricola
Right arrow Articles by Boone, D. R.
Right arrow Articles by Liu, Y.

 Previous Article  |  Next Article 

Appl Environ Microbiol. 1989 July; 55(7): 1735-1741
Copyright © 1989, American Society for Microbiology. All Rights Reserved.

Diffusion of the Interspecies Electron Carriers H2 and Formate in Methanogenic Ecosystems and Its Implications in the Measurement of Km for H2 or Formate Uptake

David R. Boone*, Richard L. Johnson and Yitai Liu

Environmental Science and Engineering, Oregon Graduate Center, 19600 N.W. Von Neumann Drive, Beaverton, Oregon 97006-1999

ABSTRACT

We calculated the potential H2 and formate diffusion between microbes and found that at H2 concentrations commonly found in nature, H2 could not diffuse rapidly enough to dispersed methanogenic cells to account for the rate of methane synthesis but formate could. Our calculations were based on individual organisms dispersed in the medium, as supported by microscopic observations of butyrate-degrading cocultures. We isolated an axenic culture of Syntrophomonas wolfei and cultivated it on butyrate in syntrophic coculture with Methanobacterium formicicum; during growth the H2 concentration was 63 nM (10.6 Pa). S. wolfei contained formate dehydrogenase activity (as does M. formicicum), which would allow interspecies formate transfer in that coculture. Thus, interspecies formate transfer may be the predominant mechanism of syntrophy. Our diffusion calculations also indicated that H2 concentration at the cell surface of H2-consuming organisms was low but increased to approximately the bulk-fluid concentration at a distance of about 10 µm from the surface. Thus, routine estimation of kinetic parameters would greatly overestimate the Km for H2 or formate.

FOOTNOTES

* Corresponding author.

Appl Environ Microbiol. 1989 July; 55(7): 1735-1741
Copyright © 1989, American Society for Microbiology. All Rights Reserved.



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 © 1989 by the American Society for Microbiology. All rights reserved.