The procedure of Straub (1) for the preparation of crystalline lactic dehydrogenase (EC 1.1.1.27, L-lactate :NAD oxidoreductase) from heart gives a product containing more than one protein component on electrophoresis (2, 3) and column chromatography (4). This time-consuming procedure, which results in yields of less than 20%, must therefore be supplemented by other techniques to achieve an enz...

The supernatants of the homogenates from normal and cancerous human prostatic tissue run on polyacrylamide gel electrophoresis have 2 major electrophoretic bands when stained for prostatic acid phosphatase. The ratios of the electrophoretically distinguishable isoenzymes differ in normal and cancerous tissues. Similar distinctions between isoenzymes in normal and cancerous prostates are observe...

The membrane-bound enzyme ferrochelatase (protoheme ferro-lyase, EC 4.99.1.1) was purified from isolated membrane fragments of Spirillum itersonii approximately 490-fold. Purification was achieved by solubilization with chaotropic salts followed by ammonium sulfate fractionation, diethylaminoethyl-cellulose chromatography, and gel filtration on Sephadex G-200. The purified enzyme has an apparen...

An enzyme which catalyzes the hydrolytic cleavage of various ribonucleosides to free base and ribose components has been obtained from cells of Pseudomonas fluorescens and purified about 300-fold by fractionation with protamine sulfate, ammonium sulfate, alumina Cy, and diethylaminoethyl cellulose. The preparation thus purEed catalyzes the hydrolysis of about 50 moles of uridine per min per mg ...

The final step in the biosynthesis of mycophenolic acid involves the transfer of a methyl group from S-adenosylmethionine to demethylmycophenolic acid. The enzyme, S-adenosylmethionine:demethylmycophenolic acid O-methyltransferase, was isolated from Penicillium stoloniferum and purified 2,700-fold by ammonium sulfate fractionation and diethylaminoethyl-cellulose and Sephadex G-200 chromatograph...

The subcellular localization of the starch biosynthetic and degradative enzymes of spinach leaves was carried out by measuring the distribution of the enzymes in a crude chloroplast pellet and soluble protein fraction, and by the separation on sucrose density gradients of intact organelles, chloroplasts, peroxisomes, and mitochondria of a protoplast lysate. ADP-Glucose pyrophosphorylase, starch...

The isoenzyme pattern of chorismate mutase (EC 5.4.99.5) was examined by diethylaminoethyl-cellulose chromatography in a wide variety of plants. All plants contained a regulated form of chorismate mutase (CM-1), and most contained an additional, unregulated form (CM-2). The regulatory properties of CM-1 differed significantly between plants. Antisera prepared against CM-1 and CM-2 from Sorghum ...

Precipitins for bovine papilloma virus (BPV) which developed following experimental infection of 21 calves were character ized by diethylaminoethyl-cellulose chromatography, gel filtration with Sephadex G-200, sucrose density gradient, and ana lytic ultracentrifugation. A 19 S antibody alone was found 1 week after initial exposure to BPV which persisted at demon strable levels for 8 weeks. Both...

Cultures of Clostridium perfringens produce a factor that stimulates the thyroid. The stimulating factor has been purified 300-fold by fractionation of the growth medium with ammonium sulfate, filtration on Sephadex G-100, and chromatography on diethylaminoethyl cellulose. The purified factor contains no proteolytic activity, and has been separated from neuraminidase and lecithinase C. When inc...

The membrane adenosine triphosphatase from SfrepfoCOCCUS faecalis has been purified by heat treatment, gel filtration through Agarose, and repeated chromatography on diethylaminoethyl cellulose. The purified ATPase appears to be homogeneous as judged from gel electrophoresis and sedimentation velocity studies. Sedimentation equilibrium studies, which are presented in the succeeding paper, also ...