Autolysin A (AtlA)

Autolysin A (AtlA) is a major bacterial enzyme, primarily found in Gram-positive pathogens such as Staphylococcus aureus and Enterococcus faecalis, while its homolog LytA serves a similar role in Streptococcus pneumoniae [3, 5, 13]. It is a multifunctional peptidoglycan hydrolase that plays a critical role in cell wall maintenance, including cell wall turnover, cell division, and the separation of daughter cells [11, 13, 22]. Beyond its structural roles, AtlA is a key virulence factor involved in biofilm formation and the release of extracellular DNA (eDNA), which stabilizes the biofilm matrix [3, 4, 19]. It also functions as an adhesin, mediating bacterial attachment to host extracellular matrix proteins like fibronectin and vitronectin [13, 22]. In the context of infectious diseases, Autolysin A is a significant therapeutic target [2, 7, 13]. Traditional antibiotics like penicillins and vancomycin exert their bactericidal effects partly by triggering uncontrolled autolysin activity, leading to bacterial self-destruction [1, 11, 13]. Conversely, novel therapeutic strategies focus on inhibiting AtlA to prevent biofilm formation and reduce virulence, or using recombinant autolysins (enzybiotics) as direct antibacterial agents to lyse resistant strains [2, 6, 7, 12]. However, the rapid activation of autolysins can lead to the release of pro-inflammatory bacterial components, presenting a challenge in managing the host's inflammatory response during treatment [1, 7, 10, 15].

Other names

AtlAAtlLytAN-acetylmuramoyl-L-alanine amidaseMurein hydrolasePeptidoglycan hydrolaseBifunctional autolysin

Antibiotics like penicillins and vancomycin induce bacterial autolysis by activating or derepressing autolysins; experimental inhibitors target the enzyme's catalytic domains to prevent cell wall remodeling and biofilm formation; recombinant autolysins act as enzybiotics to directly lyse the bacterial cell wall.