Peptidoglycan pentaglycyl bridge (Pentaglycine bridge)

The peptidoglycan pentaglycyl bridge is a specialized structural component of the bacterial cell wall, primarily found in Staphylococcus aureus and related species [1]. It consists of five glycine residues that form a cross-link between the epsilon-amino group of L-lysine in one peptidoglycan stem peptide and the D-alanine residue of an adjacent stem peptide [2]. This interpeptide bridge is vital for the mechanical strength and rigidity of the cell wall, enabling the bacteria to withstand significant internal osmotic pressure [3]. Because this specific pentaglycine sequence is characteristic of staphylococci and is not present in human cells, it serves as a highly specific therapeutic target [4]. The most prominent agent targeting this structure is lysostaphin, a glycylglycine endopeptidase that cleaves the bonds within the pentaglycine bridge, resulting in rapid cell wall degradation and osmotic lysis [1, 5]. This target is particularly significant in the context of treating multidrug-resistant infections, such as those caused by Methicillin-resistant Staphylococcus aureus (MRSA) [5]. Sources: [1] https://pubmed.ncbi.nlm.nih.gov/15105405/ [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3950588/ [3] https://micro.magnet.fsu.edu/cells/bacteriacellwall/index.html [4] https://www.uniprot.org/keywords/KW-0573 [5] https://www.frontiersin.org/articles/10.3389/fmicb.2019.01152/full

Other names

Pentaglycine cross-bridge(Gly)5 bridgePeptidoglycan interpeptide bridgePentaglycyl interpeptide bridgePentaglycine cross-link

Enzymatic cleavage of the glycyl-glycine bonds within the pentaglycine bridge, leading to cell wall degradation and osmotic lysis [1, 4].