Related Experiment Video
Updated: Aug 15, 2026

Introduction to Solid Supported Membrane Based Electrophysiology
Published on: May 11, 2013
Characterization of a novel L-serine transport system in Escherichia coli
1Department of Microbiology, Faculty of Pharmaceutical Sciences, Okayama University, Japan.
Abstract:
A novel transport system for L-serine was found in Escherichia coli cells grown on medium containing amino acid mixture. This novel system is distinguishable from the known three transport systems for L-serine, namely, the serine-threonine system, one of the leucine-isoleucine-valine systems, and the glycine-alanine system. Uptake of L-serine via this novel system was inhibited by none of the amino acids tested, indicating that it is highly specific for L-serine. This system was induced by L-leucine, but not by L-serine. The Km for L-serine was 50 microM, and the Vmax was 23 nmol/min per mg of cell protein. Transport of L-serine via this system was strongly inhibited by KCN, an inhibitor of the respiratory chain, or by carbonyl cyanide m-chlorophenylhydrazone, an H+ conductor. Uptake of H+ was induced by L-serine influx. These results indicate that an H+-serine cotransport mechanism is operative in this novel L-serine transport system.
More Related Videos
Related Concept Videos
Secondary Active Transport
Cotranslational Protein Translocation
Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...
Bacterial Translocation and Protein Secretion
Gram-negative Bacterial Protein Secretion Systems
Chemotaxis in E. coli
Stringent Response in E. coli

