Open AccessNaturally Split Inteins Assemble through a “Capture and Collapse” Mechanism
Author(s) -
Neel H. Shah,
Ertan Eryilmaz,
David Cowburn,
Tom W. Muir
Publication year - 2013
Publication title -
journal of the american chemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.115
H-Index - 612
eISSN - 1520-5126
pISSN - 0002-7863
DOI - 10.1021/ja4104364
Subject(s) - intein , protein splicing , chemistry , protein evolution , protein engineering , rna splicing , computational biology , mechanism (biology) , chemical biology , nanotechnology , biochemistry , gene , biology , physics , rna , quantum mechanics , enzyme , materials science
Split inteins are a class of naturally occurring proteins that carry out protein splicing in trans. The chemical mechanism of protein trans-splicing is well-understood and has been exploited to develop several powerful protein engineering technologies. Split intein chemistry is preceded by efficient molecular recognition between two protomers that become intertwined in their bound state. It is currently unclear how this unique topology is achieved upon fragment association. Using biophysical techniques in conjunction with protein engineering methods, including segmental isotopic labeling, we show that one split intein fragment is partly folded, while the other is completely disordered. These polypeptides capture each other through their disordered regions and form an ordered intermediate with native-like structure at their interface. This intermediate then collapses into the canonical intein fold. This mechanism provides insight into the evolutionary constraints on split intein assembly and should enhance the development of split intein-based technologies.