An Unusually Rapid Protein Backbone Modification Stabilizes the Essential Bacterial Enzyme MurA.

ABSTRACT: Proteins are subject to spontaneous rearrangements of their backbones. Most prominently, asparagine and aspartate residues isomerize to their β-linked isomer, isoaspartate (isoAsp), on time scales ranging from days to centuries. Such modifications are typically considered "molecular wear-and-tear", destroying protein function. However, the observation that some proteins, including the essential bacterial enzyme MurA, harbor stoichiometric amounts of isoAsp suggests that this modification can confer advantageous properties. Here, we demonstrate that nature exploits an isoAsp residue within a hairpin to stabilize MurA. We found that isoAsp formation in MurA is unusually rapid and critically dependent on folding status. Moreover, perturbation of the isoAsp-containing hairpin via site-directed

SUBMITTER: Zhang T 

PROVIDER: S-EPMC7614768 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature