Robinson N A, Clark J E, Wood H G
J Biol Chem. 1987 Apr 15;262(11):5216-22.
Polyphosphate kinase from Propionibacterium shermanii was purified to 70% homogeneity and shown to be a monomeric enzyme of molecular weight 83,000 +/- 3,000. It was demonstrated that short chains of polyphosphate serve as primers by using [32P]polyphosphate, 6-80 residues in length for synthesis of long-chain polyphosphate glucokinase, the radiolabel was found to be at the end of the polymer, proving that the mechanism of elongation of polyphosphate by polyphosphate kinase is strictly processive. Only 1 out of 3-8 of the polyphosphate chains contained the primer, indicating that there is a second unknown pathway of initiation which does not involve the polyphosphate primer. The termination of polyphosphate synthesis was investigated. With polyphosphate as a primer, the majority of the synthesized polyphosphate was 750 residues in length. With phosphate, in place of the polyphosphate primer, the major portion was about 2,000 residues in length but there was a large span of chain lengths down to 300. Termination is influenced by pH, temperature, and the concentration of the polyphosphate primer, with the chain length decreasing as either the temperature or the concentration of primer is increased.
来自谢氏丙酸杆菌的多聚磷酸激酶被纯化至70%的纯度，结果表明它是一种分子量为83,000±3,000的单体酶。利用[32P]多聚磷酸证明，长度为6 - 80个残基的短链多聚磷酸可作为引物用于合成长链多聚磷酸葡糖激酶，放射性标记位于聚合物末端，这证明多聚磷酸激酶延长多聚磷酸的机制是严格连续的。每3 - 8条多聚磷酸链中只有1条含有引物，这表明存在另一种未知的起始途径，该途径不涉及多聚磷酸引物。对多聚磷酸合成的终止进行了研究。以多聚磷酸作为引物时，合成的多聚磷酸大多数长度为750个残基。用磷酸盐代替多聚磷酸引物时，主要部分长度约为2,000个残基，但链长范围很大，短至300个残基。终止受pH、温度和多聚磷酸引物浓度的影响，随着温度或引物浓度的增加，链长会缩短。
