Recommended Name ?Protease lasA
Alternative Name ?LasA protease
bacteriocin LasA
Uniprot IDP14789
General Mode of ActionEnzymatic cleavage of peptidoglycan which results in a rapid lysis of the bacterial cell.
phiBIOTICS Family ?Metallopeptidase
Reaction ?1. Catalysis of the hydrolysis of internal, alpha-peptide bonds in a polypeptide chain by a mechanism in which water acts as a nucleophile, one or two metal ions hold the water molecule in place, and charged amino acid side chains are ligands for the metal ions
    EC: 3.4.24.-
    Corresponding Pfam domain: Peptidase_M23
    Evidence: experimental (PubMed: 20026068)
Source Organism ?Pseudomonas aeruginosa
Target Organism ?Staphylococcus aureus
Disease ?Infective endocarditis
Nosocomial infections
State ?Tested
Reference ?20026068

Studies found: 1

Antimicrobial Agent
Study Type
AdministrationRelevant ResultsAdverse Effects and Other IssuesReference ?
LasA in vivo
  • S. aureus (MSSA and MRSA) keratitis in rabbit eyes.

When treatment of keratitis (induced by intrastromal injection) was initiated early (4 h) after infection, practically all of the MSSA- and MRSA-infected corneas were sterilized by LasA protease. Its efficacy in eradicating the bacteria was comparable to those of lysostaphin and vancomycin. By contrast, most of the control corneas were heavily infected, with median values of 4.5x106 (MSSA) and 5x105 (MRSA) CFU/cornea.

When treatment was initiated late (10 h) after infection, LasA protease reduced the numbers of CFU in both MSSA- and MRSA-infected corneas by 3 to 4 orders of magnitude compared to the numbers of CFU for the controls. It was more effective than vancomycin in eradicating MRSA cells.

In both the early- and the late-treatment protocols, the clinical scores for eyes treated with LasA protease were significantly lower than those for the eyes of the corresponding controls and comparable to those for the lysostaphin- and vancomycin-treated eyes.