Soulié J M, Buc J, Rivière M, Ricard J
Eur J Biochem. 1985 Nov 4;152(3):565-8. doi: 10.1111/j.1432-1033.1985.tb09232.x.
Thioredoxin fB, the protein activator of chloroplastic fructose 1,6-bisphosphatase, strongly binds its target enzyme with a stoichiometry of one protein dimer per enzyme tetramer. The thioredoxin binding site is distinct from the active site and the dissociation constant of the protein-enzyme complex has the extremely small value of 769 nM at pH 7.5. This interaction involves both ionic and hydrophobic contributions and is enhanced by a pH increase from 7 to 8. These results suggest that the above molecular properties may be involved in the light activation of chloroplastic fructose bisphosphatase.
硫氧还蛋白fB是叶绿体果糖1,6-二磷酸酶的蛋白质激活剂，它以每个酶四聚体对应一个蛋白质二聚体的化学计量比与靶酶紧密结合。硫氧还蛋白结合位点与活性位点不同，在pH 7.5时，蛋白质-酶复合物的解离常数极低，仅为769 nM。这种相互作用涉及离子和疏水作用，并且随着pH从7升高到8而增强。这些结果表明，上述分子特性可能参与了叶绿体果糖二磷酸酶的光激活过程。
