Genetics and regulation of peptidase N in Escherichia coli K-12.

AUTOR(ES)

McCaman, M T

RESUMO

Escherichia coli K-12 strains contain a cytoplasmic activity, peptidase N, capable of hydrolyzing alanine-p-nitroanilide. Mutations in the structural gene for the enzyme, pepN, were mapped, and the properties of mutant strains were examined. The pepN locus lay between ompF and asnS at approximately 20.8 min on the E. coli chromosome. Loss of peptidase N activity through mutation had no apparent effect on the growth rate or nutritional needs of the cell. Enzyme levels in wild-type strains were constant throughout the growth cycle and were constitutive in all of the growth media tested. Starvation for carbon, nitrogen, or phosphate also did not alter enzyme levels. Constitutive expression of peptidase N is consistent with the idea that the enzyme plays a significant role in the degradation of intracellularly generated peptides.

Documentos Relacionados

• Transcriptional regulation of katE in Escherichia coli K-12.
• Regulation of D-arabinose utilization in Escherichia coli K-12.
• Genetic regulation of the glyoxylate shunt in Escherichia coli K-12.
• Regulation of aromatic amino acid transport systems in Escherichia coli K-12.
• Anaerobic regulation of pyruvate formate-lyase from Escherichia coli K-12.