Structure of catalytically competent intein caught in a redox trap with functional and evolutionary implications.
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ABSTRACT:
SUBMITTER: Callahan BP
PROVIDER: S-EPMC3087850 | biostudies-literature | 2011 May
REPOSITORIES: biostudies-literature
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Structure of catalytically competent intein caught in a redox trap with functional and evolutionary implications.
Callahan Brian P BP Topilina Natalya I NI Stanger Matthew J MJ Van Roey Patrick P Belfort Marlene M
Nature structural & molecular biology 20110403 5
Here we describe self-splicing proteins, called inteins, that function as redox-responsive switches in bacteria. Redox regulation was achieved by engineering a disulfide bond between the intein's catalytic cysteine and a cysteine in the flanking 'extein' sequence. This interaction was validated by an X-ray structure, which includes a transient splice junction. A natural analog of the designed system was identified in Pyrococcus abyssi, suggesting an unprecedented form of adaptive, post-translati ...[more]
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