11 Pyruvate Kinase

Abstract

This chapter describes pyruvate kinase. The enzyme has a number of attributes that make it of particular interest to various investigators. It was the first and perhaps the most clearly apparent example of an enzyme with an absolute requirement for a monovalent cation for its catalytic activity. The skeletal muscle enzyme was quite easily obtained in good yields of high purity and was stable over a period of a year. It was also recognized quite early to be a multisite subunit containing protein. In contrast, the enzyme from other sources has been somewhat difficult to stabilize both during and after purification. Skeletal muscle pyruvate kinase is most commonly prepared from rabbit muscle by the method of Tietz and Ochoa. The basic procedure utilized no chromatographic steps and can be conveniently scaled up to produce gram quantities of enzyme in a few days starting with commercially available frozen muscle. In this chapter, molecular properties of pyruvate kinase are described. Enzyme purification, composition, structure, chemical modification, and conformational change are explained. Catalytic properties are also described in the chapter.