This Article
Right arrow Full Text
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 Button, D. K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Button, D. K.

 Previous Article  |  Next Article 

Microbiology and Molecular Biology Reviews, September 1998, p. 636-645, Vol. 62, No. 3
1092-2172/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.

Nutrient Uptake by Microorganisms according to Kinetic Parameters from Theory as Related to Cytoarchitecture

D. K. Button*

Institute of Marine Science and Department of Chemistry and Biochemistry, University of Alaska, Fairbanks, Alaska 99775

The abilities of organisms to sequester substrate are described by the two kinetic constants specific affinity, a°, and maximal velocity Vmax. Specific affinity is derived from the frequency of substrate-molecule collisions with permease sites on the cell surface at subsaturating concentrations of substrates. Vmax is derived from the number of permeases and the effective residence time, tau , of the transported molecule on the permease. The results may be analyzed with affinity plots (v/S versus v, where v is the rate of substrate uptake), which extrapolate to the specific affinity and are usually concave up. A third derived parameter, the affinity constant KA, is similar to KM but is compared to the specific affinity rather than Vmax  and is defined as the concentration of substrate necessary to reduce the specific affinity by half. It can be determined in the absence of a maximal velocity measurement and is equal to the Michaelis constant for a system with hyperbolic kinetics. Both are taken as a measure of tau , with departure of KM from KA being affected by permease/enzyme ratios. Compilation of kinetic data indicates a 108-fold range in specific affinities and a smaller (103-fold) range in Vmax values. Data suggest that both specific affinities and maximal velocities can be underestimated by protocols which interrupt nutrient flow prior to kinetic analysis. A previously reported inverse relationship between specific affinity and saturation constants was confirmed. Comparisons of affinities with ambient concentrations of substrates indicated that only the largest a°S values are compatible with growth in natural systems.

* Mailing address: Institute of Marine Science, University of Alaska, Fairbanks, AK 99775. Phone: (907) 474-7708. Fax: (907) 474-7204. E-mail: dkbutton{at}ims.uaf.edu.

Microbiology and Molecular Biology Reviews, September 1998, p. 636-645, Vol. 62, No. 3
1092-2172/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:

  • Church, M. J. (2009). The trophic tapestry of the sea. Proc. Natl. Acad. Sci. USA 106: 15519-15520 [Full Text]  
  • Suar, M., van der Meer, J. R., Lawlor, K., Holliger, C., Lal, R. (2004). Dynamics of Multiple lin Gene Expression in Sphingomonas paucimobilis B90A in Response to Different Hexachlorocyclohexane Isomers. Appl. Environ. Microbiol. 70: 6650-6656 [Abstract] [Full Text]  
  • Button, D. K., Robertson, B., Gustafson, E., Zhao, X. (2004). Experimental and Theoretical Bases of Specific Affinity, a Cytoarchitecture-Based Formulation of Nutrient Collection Proposed To Supercede the Michaelis-Menten Paradigm of Microbial Kinetics. Appl. Environ. Microbiol. 70: 5511-5521 [Abstract] [Full Text]  
  • Rapp, P. (2001). Multiphasic Kinetics of Transformation of 1,2,4-Trichlorobenzene at Nano- and Micromolar Concentrations by Burkholderia sp. Strain PS14. Appl. Environ. Microbiol. 67: 3496-3500 [Abstract] [Full Text]  
  • Button, D. K., Robertson, B. R. (2001). Determination of DNA Content of Aquatic Bacteria by Flow Cytometry. Appl. Environ. Microbiol. 67: 1636-1645 [Abstract] [Full Text]  
  • Dunfield, P. F., Conrad, R. (2000). Starvation Alters the Apparent Half-Saturation Constant for Methane in the Type II Methanotroph Methylocystis Strain LR1. Appl. Environ. Microbiol. 66: 4136-4138 [Abstract] [Full Text]  
  • Button, D. K., Robertson, B. R., Lepp, P. W., Schmidt, T. M. (1998). A Small, Dilute-Cytoplasm, High-Affinity, Novel Bacterium Isolated by Extinction Culture and Having Kinetic Constants Compatible with Growth at Ambient Concentrations of Dissolved Nutrients in Seawater. Appl. Environ. Microbiol. 64: 4467-4476 [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»