A naturally occurring standalone TrpB enzyme provides insights into allosteric communication within tryptophan synthase.

ABSTRACT: Allosteric regulation of catalytic activity is a widespread property of multi-enzyme complexes. The tryptophan synthase is a prototypical allosteric enzyme where the constituting α (TrpA) and β (TrpB) subunits mutually activate each other in a manner that is incompletely understood. Experimental and computational studies have shown that LBCA-TrpB from the last bacterial common ancestor contains six residues (Res₆) distal from the active site that allow for high stand-alone catalytic activity in the absence of a TrpA subunit. In the present study, a database search revealed that Res₆ is also present in the extant plTrpB from Pelodictyon luteolum. The plTrpB enzyme showed a high stand-alone activity and only a moderate activation by plTrpA. The replacement of LBCA-Res

SUBMITTER: Kinateder T 

PROVIDER: S-EPMC11917138 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature