Sinev M A, Razgulyaev O I, Vas M, Timchenko A A, Ptitsyn O B
Institute of Protein Research, Academy of Sciences of the USSR, Pushchino, Moscow Region.
Eur J Biochem. 1989 Mar 1;180(1):61-6. doi: 10.1111/j.1432-1033.1989.tb14615.x.
Diffuse X-ray-scattering data give evidence for large-scale structural change in pig muscle 3-phosphoglycerate kinase upon substrate binding. Simultaneous binding of 3-phosphoglycerate and MgATP either to the unmodified enzyme or to its active methylated derivative leads to about an 0.1-nm decrease in radius of gyration. These data coincide well with the previous data for yeast 3-phosphoglycerate kinase. When, instead of methylation, the two reactive thiol groups of pig muscle 3-phosphoglycerate kinase are carboxamidomethylated, the enzyme becomes inactive and the radii of gyration of its 'apo' and 'holo' forms do not differ within limits of experimental error. Thus, a correlation exists between the activity of 3-phosphoglycerate kinase and its substrate-induced large-scale conformational change. This correlation is a strong argument in favor of the functional importance of domain locking in the reaction catalyzed by 3-phosphoglycerate kinase.
