Lactic Oxidase of Pneumococcus

Abstract

Ephrussi-Taylor (1954) has described a pneumococcal transforming agent which she called the LC (large colony) agent, because its first-recognized effect was to increase the size of pneumococcal colonies grown on blood agar plates. She also showed that cell suspensions of pneumococci which possess the agent have a diminished ability to respire in the presence of glucose, fail to oxidize lactate, and produce much less H202 in the course of glucose oxidation than do the normal pneumococci which do not possess this agent. Since the large colony agent seemed to act, at least in part, by blocking an enzyme responsible for the oxidation of lactic acid, it appeared desirable to characterize this enzyme. The present paper describes the partial purification of pneumococcal lactic oxidase, and provides evidence that it is a typical flavoprotein and that it is absent in the large colony strain. MATERIALS AND METHODS Pneumococcal strains. The two strains of Diplococcus pneumoniae used in this study were kindly supplied by Dr. H. Ephrussi-Taylor. One was the normal rough strain R36A derived originally from type II, and the other was made by transformation of normal R36A with the large colony agent prepared originally from the strain A66 (Ephrussi-Taylor, 1954). Throughout this paper, the normal strain of R36A and the large colony strain of R36A will be referred to as the normal and LC strains, respectively. The stock culture of the normal strain was maintained on blood heart infusion medium (Difco). The LC 1 This research was aided by grants from the American Cancer Society and from the Wallace C. and Clara A. Abbott Memorial Fund of the University of Chicago. The material in this paper is taken in part from a thesis submitted by S. Udaka in partial fulfillment of the requirements for an M.S. degree, and from a thesis submitted by J. Koukol in partial fulfillment of the requirements for a Ph.D. degree.

GLYCOLIC ACID OXIDATION BYESCHERICHIA COLIADAPTED TO GLYCOLATE

“…Separation of the apoenzyme from glycolic acid oxidase was tried by the method of Warburg and Christian (1938) as modified by Frigerio and Harbury (1958) or by the modified method of Udaka, Koukol, and Vennesland (1959). The preparations obtained were not reactivated by FMN nor FAD, probably because of inactivation of the enzyme in an acidic solution.…”

Hydrogen Peroxide in Acute Otitis Media in Guinea Pigs

“…Avery and Neill ( 10 ) demonstrated in 1924 that under aerobic conditions, pneumococcus produces hydrogen peroxide. Udaka et al subsequently described the mechanism in which O 2 and lactate are substrates for pneumococcus H 2 O 2 formation catalyzed by the enzyme lactate oxidase ( 11 ). The significance of H 2 O 2 production by pneumococcus is highlighted in humans with chronic granulomatous disease.…”

Crystallization and properties of l-lactate oxidase from Mycobacterium smegmatis

“…Unlike the lactate oxidase from Diplococcus pneumoniae (Udaka, Koukol & Vennesland, 1959), the oc-hydroxy acid oxidase from Tetrahymena pyriformia (Eichel, 1966) and other NAD-independent lactate dehydrogenases, the mycobacterial lactate oxidase exhibits a marked specificity for both substrate and electron acceptors. Further, if pyruvate is formed during the catalysis it is present only as an enzyme-bound intermediate (Cousins, 1956;Sutton, 1957).…”