A study of the substrate specificity of aminopeptidase N from Lactococcus lactis subsp. cremoris Wg2

Appl Microbiol Biotechnol. 1995 Dec;44(1-2):100-5. doi: 10.1007/BF00164487.

Abstract

A systematic study was made of the ability of aminopeptidase N from Lactococcus lactis subsp. cremoris Wg2 to hydrolyse different peptide substrates. The enzyme showed a marked preference for substrates containing arginine as the N-terminal residue but, to a lesser extent, was also capable of cleaving other residues such as lysine and leucine. There was a tendency for the activity to increase with the hydrophobicity index of the C-terminal residue of dipeptide substrates. It was also observed that the enzyme tended to have higher affinities but lower Vmax values for tripeptides with hydrophobic C-terminal residues. The values determined for Km and Vmax increased with chain length for oligopeptides of the general formula Lys-Phe-(Gly)n, the optimum, as determined from Vmax/Km, being when n = 4. Typical Km values for the most effective substrates were in the range 0.2-0.6 mM.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • CD13 Antigens / metabolism*
  • Kinetics
  • Lactococcus lactis / enzymology*
  • Molecular Sequence Data
  • Substrate Specificity

Substances

  • CD13 Antigens