2024

Tossavainen, Helena; Pitkänen, Ilona; Antenucci, Lina; Thapa, Chandan; Permi, Perttu

S. aureus resistance to antibiotics has increased rapidly. MRSA strains can simultaneously be resistant to many different classes of antibiotics, including the so-called “last-resort” drugs. Resistance complicates treatment, increases mortality and substantially increases the cost of treatment. The need for new drugs against (multi)resistant S. aureus is high. M23B family peptidoglycan hydrolases, enzymes that can kill S. aureus by cleaving glycine-glycine peptide bonds in S. aureus cell wall are attractive targets for drug development because of their binding specificity and lytic activity. M23B enzymes lysostaphin, LytU and LytM have closely similar catalytic domain structures. They however differ in their lytic activities, which can arise from non-conserved residues in the catalytic groove and surrounding loops or differences in dynamics. We report here the near complete 1 H/13C/15N resonance assignment of the catalytic domain of LytM, residues 185–316. The chemical shift data allow comparative structural and functional studies between the enzymes and is essential for understanding how these hydrolases degrade the cell wall.