A distinctive family of L,D-transpeptidases catalyzing L-Ala-mDAP crosslinks in Alpha- and Betaproteobacteria.

Autor: Espaillat A; Department of Molecular Biology and Laboratory for Molecular Infection Medicine Sweden, Umeå Centre for Microbial Research, SciLifeLab, Umeå University, Umeå, Sweden.; Chr. Hansen A/S, Microbial Physiology, R&D, 2970, Hoersholm, Denmark., Alvarez L; Department of Molecular Biology and Laboratory for Molecular Infection Medicine Sweden, Umeå Centre for Microbial Research, SciLifeLab, Umeå University, Umeå, Sweden., Torrens G; Department of Molecular Biology and Laboratory for Molecular Infection Medicine Sweden, Umeå Centre for Microbial Research, SciLifeLab, Umeå University, Umeå, Sweden., Ter Beek J; Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden.; Wallenberg Centre for Molecular Medicine, Umeå University, Umeå, Sweden., Miguel-Ruano V; Department of Crystallography and Structural Biology, Institute of Physical Chemistry 'Blas Cabrera', CSIC, Madrid, Spain., Irazoki O; Department of Molecular Biology and Laboratory for Molecular Infection Medicine Sweden, Umeå Centre for Microbial Research, SciLifeLab, Umeå University, Umeå, Sweden., Gago F; Department of Biomedical Sciences & IQM-CSIC Associate Unit, School of Medicine and Health Sciences, University of Alcalá, E-28805, Madrid, Alcalá de Henares, Spain., Hermoso JA; Department of Crystallography and Structural Biology, Institute of Physical Chemistry 'Blas Cabrera', CSIC, Madrid, Spain., Berntsson RP; Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden.; Wallenberg Centre for Molecular Medicine, Umeå University, Umeå, Sweden., Cava F; Department of Molecular Biology and Laboratory for Molecular Infection Medicine Sweden, Umeå Centre for Microbial Research, SciLifeLab, Umeå University, Umeå, Sweden. felipe.cava@umu.se.
Jazyk: angličtina
Zdroj: Nature communications [Nat Commun] 2024 Feb 13; Vol. 15 (1), pp. 1343. Date of Electronic Publication: 2024 Feb 13.
DOI: 10.1038/s41467-024-45620-5
Abstrakt: The bacterial cell-wall peptidoglycan is made of glycan strands crosslinked by short peptide stems. Crosslinks are catalyzed by DD-transpeptidases (4,3-crosslinks) and LD-transpeptidases (3,3-crosslinks). However, recent research on non-model species has revealed novel crosslink types, suggesting the existence of uncharacterized enzymes. Here, we identify an LD-transpeptidase, LDT Go , that generates 1,3-crosslinks in the acetic-acid bacterium Gluconobacter oxydans. LDT Go -like proteins are found in Alpha- and Betaproteobacteria lacking LD3,3-transpeptidases. In contrast with the strict specificity of typical LD- and DD-transpeptidases, LDT Go can use non-terminal amino acid moieties for crosslinking. A high-resolution crystal structure of LDT Go reveals unique features when compared to LD3,3-transpeptidases, including a proline-rich region that appears to limit substrate access, and a cavity accommodating both glycan chain and peptide stem from donor muropeptides. Finally, we show that DD-crosslink turnover is involved in supplying the necessary substrate for LD1,3-transpeptidation. This phenomenon underscores the interplay between distinct crosslinking mechanisms in maintaining cell wall integrity in G. oxydans.
(© 2024. The Author(s).)
Databáze: MEDLINE
Externí odkaz: