Revisiting glutaraldehyde cross-linking: the case of the Arg-Lys intermolecular doublet.
In addition to the common use of glutaraldehyde to nonspecifically cross-link protein crystals through lysine residues disposed on the surface of the protein, the use of gentle vapour diffusion of glutaraldehyde offers a convenient way to limit polymerization and to allow slow diffusion throughout the crystal. In the case of trimeric barnase crystals, a specific cross-link was observed between an lysine side chain and an arginine side chain that were spatially disposed at the ideal distance on the protein surface in the three monomers. Here, the direct observation of a specific Lys-Arg cross-link site is reported and a mechanism is proposed for the reaction.
Salem
Michèle
M
Laboratoire de Cristallographie et RMN Biologiques (UMR 8015 CNRS), Faculté de Pharmacie, Université Descartes, 4 Avenue de l'Observatoire, 75006 Paris, France. michele.salem@parisdescartes.fr
Mauguen
Yves
Y
Prangé
Thierry
T
D001120:Arginine / Q000737:chemistry; D001407:Bacillus / Q000201:enzymology*; D001426:Bacterial Proteins; D003432:Cross-Linking Reagents / Q000737:chemistry*; D018360:Crystallography, X-Ray; D005976:Glutaral / Q000737:chemistry*; D008239:Lysine / Q000737:chemistry; D008958:Models, Molecular; D017434:Protein Structure, Tertiary; D012260:Ribonucleases / Q000737:chemistry*
D001426:Bacterial Proteins; D003432:Cross-Linking Reagents; D001120:Arginine; D012260:Ribonucleases; C019760:Bacillus amyloliquefaciens ribonuclease; D008239:Lysine; D005976:Glutaral