Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.9.3.1 (cytochrome oxidase)
 8,822 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Highly purified tonoplast and plasmamembrane vesicles were isolated from microsomes of Catharanthus roseus (L.) G. Don. by preparative free-flow electrophoresis. The relative amounts of tonoplast and plasma-membrane vesicles in the total microsomes varied with the pH of the grinding medium. The most electronegative fractions were identified as tonoplast using nitrate-inhibited, azide-resistant Mg(2+)-ATPase and pyrophosphatase activities as enzyme markers. The least electronegative fractions were identified as plasma membrane using glucan-synthase-II and UDPG:sterolglucosyl-transferase activities as enzyme markers. Other membrane markers, latent inosine-5'-diphosphatase (Golgi), NADPH-cytochrome-c reductase (ER) and cytochrome-c oxidase (mitochondria) were recovered in the fractions intermediate between tonoplast and plasma membrane and did not contaminate either the tonoplast or the plasma-membrane fractions. In the course of searching for a reliable marker for tonoplast, the pyrophosphatase activity was found to be essentially associated with the tonoplast fractions purified by free-flow electrophoresis from C. roseus and other plant materials. The degree of sealing of the tonoplast and plasmamembrane vesicles was probed by their ability to pump protons (measurements of quinacrine quenching) and to generate a membrane potential (absorption spectroscopy of Oxonol VI). A critical evaluation of vesicles sidedness is presented.
...
PMID:Preparation of sealed tonoplast and plasma-membrane vesicles from Catharanthus roseus (L.) G. Don. cells by free-flow electrophoresis. 2419 36


<< Previous 1 2