title: Effect of alpha-crystallin on thermal denaturation and aggregation of rabbit muscle glyceraldehyde-3-phosphate dehydrogenase.
abstract: The study of thermal denaturation of rabbit muscle glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in the presence of alpha-crystallin by differential scanning calorimetry (DSC) showed that the position of the maximum on the DSC profile (T(max)) was shifted toward lower temperatures with increasing alpha-crystallin concentration. The diminishing GAPDH stability in the presence of alpha-crystallin has been explained assuming that heating of GAPDH induces dissociation of the tetrameric form of the enzyme into dimers interacting with alpha-crystallin. The dissociation of the enzyme tetramer was shown by sedimentation velocity at 45 degrees C. Suppression of thermal aggregation of GAPDH by alpha-crystallin was studied by dynamic light scattering under the conditions wherein temperature was elevated at a constant rate. The construction of the light scattering intensity versus the hydrodynamic radius (R(h)) plots enabled estimating the hydrodynamic radius of the start aggregates (R(h,0)). When aggregation of GAPDH was studied in the presence of alpha-crystallin, the start aggregates of lesser size were observed.
authors.affiliation: Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, Russia.
authors.forename: Helen A
authors.initials: HA
authors.lastname: Khanova
authors.forename: Kira A
authors.initials: KA
authors.lastname: Markossian
authors.forename: Sergey Yu
authors.initials: SY
authors.lastname: Kleimenov
authors.forename: Dmitrii I
authors.initials: DI
authors.lastname: Levitsky
authors.forename: Natalia A
authors.initials: NA
authors.lastname: Chebotareva
authors.forename: Nikolay V
authors.initials: NV
authors.lastname: Golub
authors.forename: Regina A
authors.initials: RA
authors.lastname: Asryants
authors.forename: Vladimir I
authors.initials: VI
authors.lastname: Muronetz
authors.forename: Luciano
authors.initials: L
authors.lastname: Saso
authors.forename: Igor K
authors.initials: IK
authors.lastname: Yudin
authors.forename: Konstantin O
authors.initials: KO
authors.lastname: Muranov
authors.forename: Michail A
authors.initials: MA
authors.lastname: Ostrovsky
authors.forename: Boris I
authors.initials: BI
authors.lastname: Kurganov
mesh_terms: D000818:Animals; D002152:Calorimetry, Differential Scanning; D019281:Dimerization; D004795:Enzyme Stability; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000737:chemistry* / Q000378:metabolism; D009132:Muscles / Q000201:enzymology*; D011487:Protein Conformation; D011489:Protein Denaturation; D011817:Rabbits; D013696:Temperature; D038201:alpha-Crystallins
chemical_list: D038201:alpha-Crystallins; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases