The role of the jaw subdomain of peptidoglycan glycosyltransferases for lipid II polymerization.
Punekar, A.S., Samsudin, F., Lloyd, A.J., Dowson, C.G., Scott, D.J., Khalid, S., Roper, D.I.(2018) Cell Surf 2: 54-66
- PubMed: 30046666 
- DOI: https://doi.org/10.1016/j.tcsw.2018.06.002
- Primary Citation of Related Structures:  
6FTB - PubMed Abstract: 
Bacterial peptidoglycan glycosyltransferases (PGT) catalyse the essential polymerization of lipid II into linear glycan chains required for peptidoglycan biosynthesis. The PGT domain is composed of a large head subdomain and a smaller jaw subdomain and can be potently inhibited by the antibiotic moenomycin A (MoeA). We present an X-ray structure of the MoeA-bound Staphylococcus aureus monofunctional PGT enzyme, revealing electron density for a second MoeA bound to the jaw subdomain as well as the PGT donor site. Isothermal titration calorimetry confirms two drug-binding sites with markedly different affinities and positive cooperativity. Hydrophobic cluster analysis suggests that the membrane-interacting surface of the jaw subdomain has structural and physicochemical properties similar to amphipathic cationic -helical antimicrobial peptides for lipid II recognition and binding. Furthermore, molecular dynamics simulations of the drug-free and -bound forms of the enzyme demonstrate the importance of the jaw subdomain movement for lipid II selection and polymerization process and provide molecular-level insights into the mechanism of peptidoglycan biosynthesis by PGTs.
Organizational Affiliation: 
School of Life Sciences, University of Warwick, Coventry CV4 7AL, United Kingdom.