Molecular basis for substrate recognition and septum cleavage by AtlA, the major N-acetylglucosaminidase of Enterococcus faecalis

Mechanistic Insights into the Activities of Major Families of Enzymes in Bacterial Peptidoglycan Assembly and Breakdown

“…For instance, E. faecalis glucosaminidase AtlA cleaves sacculi into both monomeric and multimeric products in similar ratios irrespective of enzyme concentration, a characteristic of endolytic glycosidase. [151] In contrast, S. aureus glucosaminidase GlcA, an exolytic glycosidase, accumulates MurNAc-GlcNAc monomers as the sole products upon digestion of sacculi. [152] Among the eight LTs in E. coli, MltE [153] and MltG [154] are exclusively endolytic, whereas the other LTs either showcase solely exolytic activity (i. e., MltA, MltF) or a combination of both (i. e., MltB, MltC, MltD, Slt70).…”

“…The endolytic or exolytic activity of glycosidases can be determined by LC–MS analysis (Figure 7b, bottom). For instance, E. faecalis glucosaminidase AtlA cleaves sacculi into both monomeric and multimeric products in similar ratios irrespective of enzyme concentration, a characteristic of endolytic glycosidase [151] . In contrast, S. aureus glucosaminidase GlcA, an exolytic glycosidase, accumulates MurNAc‐GlcNAc monomers as the sole products upon digestion of sacculi [152] .…”