Display Settings:

Format

Send to:

Choose Destination
Metab Eng. 2009 Nov;11(6):409-14. doi: 10.1016/j.ymben.2009.08.004. Epub 2009 Aug 25.

Microbial maximal specific growth rate as a square-root function of biomass yield and two kinetic parameters.

Author information

  • 1Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA.

Abstract

Understanding how growth rates changes under different perturbations is fundamental to many aspect of microbial physiology. In this work, we experimentally showed that maximal specific growth rate is a square-root function of the biomass yield, the substrate turnover number, and the maximum synthesis rate of the substrate transporter under that condition. We used Escherichia coli cultures in lactose minimal medium as a model system by introducing genetic modifications, in vitro evolution, and ethanol stress to the cell. Deletion of crr affected all three parameters in different directions while deletion of ptsG decreased only the biomass yield. Ethanol stress negatively impacted all three parameters, while anaerobicity decreased biomass yield and transporter synthesis rate. In addition, laboratory evolution increased the growth rate in lactose mostly through enhancing the expression rate of the lac operon. Despite all these changes, the growth rate of the perturbed strain was successfully related to the three parameters by the square-root equation. Thus, this square-root relationship provides insight into how growth rate is altered by different physiological parameters.

PMID:
19712746
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Write to the Help Desk