title: Surface interactions of gamma-crystallins in the crystal medium in relation to their association in the eye lens.
abstract: A comparative study of intermolecular interactions in crystals of two homologous low molecular weight proteins, gamma-II and gamma-IIIb crystallins, from calf eye lens was carried out. Crystal packings for these proteins are very different: intermolecular contact areas compose about 33% of the total accessible surface area of gamma-II as compared with 13% in gamma-III. Two key residues seem to be mainly responsible for the differences in protein association in the crystal medium. These are Ser 103 and Leu 155 in gamma-II, which are replaced by Met 103 and His 155 in gamma-IIb. A similar substitution of these residues is observed in different gene products of gamma-crystallins from a number of vertebrates. This is consistent with the existence of a genetically controlled mechanism for determining intermolecular association of gamma-crystallins in the native medium of the lens.
authors.affiliation: Institute of Protein Research, Academy of Sciences of the USSR, Pushchino, Moscow Region.
authors.forename: Y V
authors.initials: YV
authors.lastname: Sergeev
authors.forename: Y N
authors.initials: YN
authors.lastname: Chirgadze
authors.forename: S E
authors.initials: SE
authors.lastname: Mylvaganam
authors.forename: H
authors.initials: H
authors.lastname: Driessen
authors.forename: C
authors.initials: C
authors.lastname: Slingsby
authors.forename: T L
authors.initials: TL
authors.lastname: Blundell
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003459:Crystallins / Q000235:genetics / Q000378:metabolism*; D003460:Crystallization; D006801:Humans; D007908:Lens, Crystalline / Q000502:physiology*; D011487:Protein Conformation; D013045:Species Specificity; D013499:Surface Properties; D014961:X-Ray Diffraction
chemical_list: D003459:Crystallins