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Internal disulfide bond acts as a switch for intein activity.

ABSTRACT: Inteins are intervening polypeptides that catalyze their own removal from flanking exteins, concomitant to the ligation of the exteins. The intein that interrupts the DP2 (large) subunit of DNA polymerase II from Methanoculleus marisnigri (Mma) can promote protein splicing. However, protein splicing can be prevented or reduced by overexpression under nonreducing conditions because of the formation of a disulfide bond between two internal intein Cys residues. This redox sensitivity leads to differential activity in different strains of E. coli as well as in different cell compartments. The redox-dependent control of in vivo protein splicing in an intein derived from an anaerobe that can occupy multiple environments hints at a possible physiological role for protein splicing.

SUBMITTER: Nicastri MC

PROVIDER: S-EPMC3801215 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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Internal disulfide bond acts as a switch for intein activity.

Nicastri Michael C MC Xega Kristina K Li Lingyun L Xie Jian J Wang Chunyu C Linhardt Robert J RJ Reitter Julie N JN Mills Kenneth V KV

Biochemistry 20130812 34

Inteins are intervening polypeptides that catalyze their own removal from flanking exteins, concomitant to the ligation of the exteins. The intein that interrupts the DP2 (large) subunit of DNA polymerase II from Methanoculleus marisnigri (Mma) can promote protein splicing. However, protein splicing can be prevented or reduced by overexpression under nonreducing conditions because of the formation of a disulfide bond between two internal intein Cys residues. This redox sensitivity leads to diffe ...[more]

PMID: 23906287

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Intramolecular disulfide bond between catalytic cysteines in an intein precursor.

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