Biochemical and Structural Characterization of an Unusual and Naturally Split Class 3 Intein.

ABSTRACT: Split inteins are indispensable tools for protein engineering because their ligation and cleavage reactions enable unique modifications of the polypeptide backbone. Three different classes of inteins have been identified according to the nature of the covalent intermediates resulting from the acyl rearrangements in the multistep protein-splicing pathway. Class 3 inteins employ a characteristic internal cysteine for a branched thioester intermediate. A bioinformatic database search of non-redundant protein sequences revealed the absence of split variants in 1701 class 3 inteins. We have discovered the first reported split class 3 intein in a metagenomics data set and report its biochemical, mechanistic and structural analysis. The AceL NrdHF intein exhibits low sequence conservation with ot

SUBMITTER: Hoffmann S 

PROVIDER: S-EPMC7891396 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature