The ywad gene from Bacillus subtilis encodes a double-zinc aminopeptidase

FEMS Microbiol Lett. 2005 Feb 1;243(1):157-63. doi: 10.1016/j.femsle.2004.12.001.


The yet uncharacterized ywad gene from Bacillus subtilis has been cloned and overexpressed in Escherichia coli. The gene product (BSAP) was purified and shown to be an aminopeptidase. The activity of BSAP was optimal at pH 8.4, the enzyme was stable for 20 min at 80 degrees C and its activity was not affected by serine protease and aspartic protease inhibitors, but was completely diminished by the Zn-chelator 1,10-phenanthroline. ZnCl2 was able to restore activity, and the binding stoichiometry of zinc to apo-BSAP indicated two Zn ions per protein molecule. BSAP exhibited high preference toward p-nitroanilide derived Arg, Lys, and Leu synthetic substrates resulting in kcat/Km values of 1-5 x 10(1) s(-1) mM(-1).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Aminopeptidases / chemistry
  • Aminopeptidases / genetics*
  • Aminopeptidases / isolation & purification
  • Aminopeptidases / metabolism*
  • Bacillus subtilis / enzymology*
  • Bacillus subtilis / genetics
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Cloning, Molecular
  • Molecular Sequence Data
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Substrate Specificity
  • Zinc / metabolism*


  • Bacterial Proteins
  • Recombinant Proteins
  • Aminopeptidases
  • Zinc