2jnq
From Proteopedia
|
Solution Structure of a KlbA Intein Precursor from Methanococcus jannaschii
Overview
Certain proteins of unicellular organisms are translated as precursor, polypeptides containing inteins (intervening proteins), which are domains, capable of performing protein splicing. These domains, in conjunction with, a single residue following the intein, catalyze their own excision from, the surrounding protein (extein) in a multistep reaction involving the, cleavage of two intein-extein peptide bonds and the formation of a new, peptide bond that ligates the two exteins to yield the mature protein. We, report here the solution NMR structure of a 186-residue precursor of the, KlbA intein from Methanococcus jannaschii, comprising the intein together, with N- and C-extein segments of 7 and 11 residues, respectively. The, intein is shown to adopt a single, well-defined globular domain, representing a HINT (Hedgehog/Intein)-type topology. Fourteen beta-strands, are arranged in a complex fold that includes four beta-hairpins and an, antiparallel beta-ribbon, and there is one alpha-helix, which is packed, against the beta-ribbon, and one turn of 3(10)-helix in the loop between, the beta-strands 8 and 9. The two extein segments show increased disorder, and form only minimal nonbonding contacts with the intein domain., Structure-based mutation experiments resulted in a proposal for functional, roles of individual residues in the intein catalytic mechanism.
About this Structure
2JNQ is a Single protein structure of sequence from Methanocaldococcus jannaschii. Full crystallographic information is available from OCA.
Reference
NMR structure of a KlbA intein precursor from Methanococcus jannaschii., Johnson MA, Southworth MW, Herrmann T, Brace L, Perler FB, Wuthrich K, Protein Sci. 2007 Jul;16(7):1316-28. PMID:17586768
Page seeded by OCA on Wed Nov 21 12:38:39 2007
