This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Vermeij, P. Articles by Vogels, G. D. Search for Related Content PubMed PubMed Citation Articles by Vermeij, P. Articles by Vogels, G. D.

 Previous Article  |  Next Article 

J. Bacteriol., 11 1997, 6640-6648, Vol 179, No. 21
Copyright © 1997, American Society for Microbiology

Cellular levels of factor 390 and methanogenic enzymes during growth of Methanobacterium thermoautotrophicum deltaH

P Vermeij, JL Pennings, SM Maassen, JT Keltjens and GD Vogels
Department of Microbiology, Faculty of Science, University of Nijmegen, The Netherlands.

Methanobacterium thermoautotrophicum deltaH was grown in a fed-batch fermentor and in a chemostat under a variety of 80% hydrogen-20% CO2 gassing regimes. During growth or after the establishment of steady- state conditions, the cells were analyzed for the content of adenylylated coenzyme F420 (factor F390-A) and other methanogenic cofactors. In addition, cells collected from the chemostat were measured for methyl coenzyme M reductase isoenzyme (MCR I and MCR II) content as well as for specific activities of coenzyme F420-dependent and H2-dependent methylenetetrahydromethanopterin dehydrogenase (F420- MDH and H2-MDH, respectively), total (viologen-reducing) and coenzyme F420-reducing hydrogenase (FRH), factor F390 synthetase, and factor F390 hydrolase. The experiments were performed to investigate how the intracellular F390 concentrations changed with the growth conditions used and how the variations were related to changes in levels of enzymes that are known to be differentially expressed. The levels of factor F390 varied in a way that is consistently understood from the biochemical mechanisms underlying its synthesis and degradation. Moreover, a remarkable correlation was observed between expression levels of MCR I and II, F420-MDH, and H2-MDH and the cellular contents of the factor. These results suggest that factor F390 is a reporter compound for hydrogen limitation and may act as a response regulator of methanogenic metabolism.

This article has been cited by other articles:

• de Poorter, L. M. I., Geerts, W. J., Keltjens, J. T. (2007). Coupling of Methanothermobacter thermautotrophicus Methane Formation and Growth in Fed-Batch and Continuous Cultures under Different H2 Gassing Regimens. Appl. Environ. Microbiol. 73: 740-749 [Abstract] [Full Text]  
• de Poorter, L. M. I., Geerts, W. J., Keltjens, J. T. (2005). Hydrogen concentrations in methane-forming cells probed by the ratios of reduced and oxidized coenzyme F420. Microbiology 151: 1697-1705 [Abstract] [Full Text]  
• Pennings, J. L. A., Keltjens, J. T., Vogels, G. D. (1998). Isolation and Characterization of Methanobacterium thermoautotrophicum Delta H Mutants Unable To Grow under Hydrogen-Deprived Conditions. J. Bacteriol. 180: 2676-2681 [Abstract] [Full Text]