SEQUENCE-ANALYSIS OF A STAPHYLOCOCCUS-AUREUS GENE ENCODING A PEPTIDOGLYCAN HYDROLASE ACTIVITY

The nucleotide (nt) sequence of a 2.0-kb NheI-XbaI DNA fragment containing a peptidoglycan hydrolase-encoding gene, lytA, tentatively identified as encoding an N-acetylmuramyl-L-alanine amidase, from Staphylococcus aureus, was determined. The nt sequencing revealed an open reading frame (ORF) of 1443 bp with a consensus ribosome-binding site located 7 nt upstream from the ATG start codon. The primary amino acid (aa) sequence deduced from the nt sequence revealed a putative protein of 481 aa residues with an M(r) of 53 815. Comparison of the aa sequence of the ORF with aa sequences in the GenBank data base (version 63, March 1990) revealed that the C-terminal sequence showed significant homology to the C-terminal sequence of lysostaphin from Staphylococcus simulans biovar staphylolyticus.