An Unprecedented Combination of Serine and Cysteine Nucleophiles in a Split Intein with an Atypical Split Site.

ABSTRACT: Protein splicing mediated by inteins is a self-processive reaction leading to the excision of the internal intein domain from a precursor protein and the concomitant ligation of the flanking sequences, the extein-N and extein-C parts, thereby reconstituting the host protein. Most inteins employ a splicing pathway in which the upstream scissile peptide bond is consecutively rearranged into two thioester or oxoester intermediates before intein excision and rearrangement into the new peptide bond occurs. The catalytically critical amino acids involved at the two splice junctions are cysteine, serine, or threonine. Notably, the only potential combination not observed so far in any of the known or engineered inteins corresponds to the transesterification from an oxoester to a thioester, which s

SUBMITTER: Bachmann AL 

PROVIDER: S-EPMC4661395 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature