Isozyme 4 of rabbit liver microsomal cytochrome P-450 was shown earlier in this laboratory to contain multiple NH2-terminal residues, whereas isozymes 2, 3a, 3b, and 3c have single, unique NH2-terminal sequences. Similar results were obtained with isozyme 4 obtained from animals that were untreated, treated with phenobarbital (which does not induce this isozyme), or induced with beta-naphthofla...

Protein kinase C (PKC) isozymes comprise a family of related enzymes. There are only limited differences between these isozymes in substrate specificity or sensitivity to activators. However, there are multiple isozymes within a cell mediating isozyme-specific functions. Differential subcellular localization has been proposed to explain this specificity. When members of the PKC family are activ...

Following blastocyst implantation, or outgrowth in vitro, the LDH isozyme pattern changes from that of the maternally inherited B subunit isozyme form (LDH-1) to a pattern dominated by A subunits (Auerbach & Brinster, 1967, 1968). In preimplantation embryos we have observed additional isozyme bands, as yet unidentified. An analysis of the pattern of newly synthesized LDH isozymes and specific a...

The intracellular localization of the activity and synthesis of three isozymes of NAD(P)(+)-glutamate dehydrogenase from the unicellular green alga Chlamydomonas reinhardtii cw-92 has been established. Isozyme activities have been located within mitochondria by using differential centrifugation techniques and discontinuous Percoll gradient separations. Experiments with protein synthesis inhibit...

The present study was aimed at the development of a somoclonal variant and isozyme marker for Phyllanthus amarus Schum & Thonn using inter-nodal segments and the enzyme peroxidase. Maximum callus proliferation was obtained on Murashige and Skoog’s medium supplemented (MS) with 1.0 mg/l of 2,4-Dichlorophenoxyacetic acid. Three weeks-old pale yellowish white semi-friable callus was used for organ...

Cytochrome P-45Oj has been purified to electrophoretic. homogeneity from hepatic microsomes of adult male rats administered ethanol and compared to the corresponding enzyme from isoniazid-treated rats. The enzymes isolated from ethanoland isoniazidtreated rats have identical chromatographic properties, minimum molecular weights, spectral properties, peptide maps, NHz-terminal sequences, immunoc...

1. Kinetic data concerning the substrate and product inhibition by pyruvate and L-lactate have been obtained with the Md and Hd fractions separated from crystalline rabbit muscle lactic dehydrogenase. 2. The studies indicate that the product inhibition by L-lactate or by pyruvate is predominantly noncompetitive for both the Mq and Hq isozymes. Ki values for product inhibition by L-lactate were ...

1. Kinetic data concerning the substrate and product inhibition by pyruvate and L-lactate have been obtained with the Md and Hd fractions separated from crystalline rabbit muscle lactic dehydrogenase. 2. The studies indicate that the product inhibition by L-lactate or by pyruvate is predominantly noncompetitive for both the Mq and Hq isozymes. Ki values for product inhibition by L-lactate were ...

Enzyme activities of tobacco leaves were compared in detergent extracts. Highest levels of chlorogenic acid oxidase, malate-NAD oxidoreductase, and acid phosphatase were obtained from bud tissues. Peroxidase activity was least in young leaves and highest in senescent leaves yellowed with Ethrel. Peroxidase zymograms obtained by means of disc electrophoresis showed differences in isozyme composi...