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 Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Filer, D. Articles by Kindler, S. H. Search for Related Content PubMed PubMed Citation Articles by Filer, D. Articles by Kindler, S. H.

Aspartokinase of Myxococcus xanthus: "Feedback Stimulation" by Required Amino Acids

Department of Microbiology, Tel Aviv University, Tel Aviv, Israel

ABSTRACT

The aspartokinase activity found in extracts of the bacterium Myxococcus xanthus was subject to feedback inhibition and feedback repression by L-threonine and L-lysine. Both types of inhibition were essentially additive. The required amino acids, L-isoleucine and L-methionine, caused considerable increase in the activity of the enzyme. This phenomenon is referred to as "feedback stimulation." The polyamine, spermidine, exerted strong enhancement of the activity even at 0.1 mM. Meso-diaminopimelate, although not inhibitory by itself, abolished the activation exerted by either L-isoleucine or L-methionine. The possible physiological significance of interactions between the various effectors is discussed.

This article has been cited by other articles:

• Wireman, J., Dworkin, M (1975). Morphogenesis and developmental interactions in myxobacteria. Science 189: 516-523