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Evidence for an Aminoendopeptidase Localized Near the Cell Surface of <em>Escherichia coli</em>.

Authors :
Lazdunski, Andrée
Murgier, Maryse
Lazdunski, Claude
Source :
European Journal of Biochemistry. Dec75 Part 2, Vol. 60 Issue 2, p349-355. 7p.
Publication Year :
1975

Abstract

An enzyme capable of hydrolyzing the substrate L-alanine p-nitroanilide has been found in the various Escherichia coli strains tested. This enzyme has been called aminoendopeptidase since it shows both activities (see accompanying paper). It is released from the cells by osmotic shock and by lysozyme-EDTA spheroplasting treatment, and 50% of the total activity is directly detectable with suspensions of intact cells. However, the release by osmotic shock or spheroplasting is not as efficient as it is for alkaline phosphatase. This periplasmic aminoendopeptidase is constitutively produced but the differential rate of synthesis is increased 4-fold when the cell growth is limited by Pi. The occurrence of this &#39;derepression&#39; is simultaneous with that of alkaline phosphatase. Increasing the concentration of inorganic phosphate in the medium has no effect on the constitutive aminoendopeptidase synthesis. The effect of phosphate starvation is specific since starvation for neither nitrogen nor carbon and energy source are effective in derepressing aminoendopeptidase. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
00142956
Volume :
60
Issue :
2
Database :
Academic Search Index
Journal :
European Journal of Biochemistry
Publication Type :
Academic Journal
Accession number :
13482349
Full Text :
https://doi.org/10.1111/j.1432-1033.1975.tb21009.x