On methylene-bridged cysteine and lysine residues in proteins.
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.
Synchrotron Radiation Research Section of MCL, National Cancer Institute, Argonne, Illinois.
Milosz
M
Ruszkowski
Synchrotron Radiation Research Section of MCL, National Cancer Institute, Argonne, Illinois.
Zbigniew
Z
Dauter
D003545:Cysteine / Q000737:chemistry; D030562:Databases, Protein; D006642:Histidinol-Phosphatase / Q000737:chemistry*; D008239:Lysine / Q000737:chemistry; D046913:Medicago truncatula / Q000201:enzymology*; D010940:Plant Proteins / Q000737:chemistry*
D010940:Plant Proteins; D006642:Histidinol-Phosphatase; D008239:Lysine; D003545:Cysteine
crosslink; cysteine; intermolecular; intramolecular; lysine; methylene bridge