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On methylene-bridged cysteine and lysine residues in proteins.

ABSTRACT: Cysteine residues ubiquitously stabilize tertiary and quaternary protein structure by formation of disulfide bridges. Here we investigate another linking interaction that involves sulfhydryl groups of cysteines, namely intra- and intermolecular methylene-bridges between cysteine and lysine residues. A number of crystal structures possessing such a linkage were identified in the Protein Data Bank. Inspection of the electron density maps and re-refinement of the nominated structures unequivocally confirmed the presence of Lys-CH2 -Cys bonds in several cases.

SUBMITTER: Ruszkowski M

PROVIDER: S-EPMC5338236 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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On methylene-bridged cysteine and lysine residues in proteins.

Ruszkowski Milosz M Dauter Zbigniew Z

Protein science : a publication of the Protein Society 20160617 9

Cysteine residues ubiquitously stabilize tertiary and quaternary protein structure by formation of disulfide bridges. Here we investigate another linking interaction that involves sulfhydryl groups of cysteines, namely intra- and intermolecular methylene-bridges between cysteine and lysine residues. A number of crystal structures possessing such a linkage were identified in the Protein Data Bank. Inspection of the electron density maps and re-refinement of the nominated structures unequivocally ...[more]

PMID: 27261771

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