|
|||||
|
|
Duroquinone-stimulated NADH oxidase and b type cytochromes in the plasma membrane of cauliflower and mung beans |
|
| Institution: | 1. Department of Critical Care Medicine, University of Pittsburgh School of Medicine, 637 Scaife Hall, 3550 Terrace Street, Pittsburgh, PA, 15261, USA;2. Department of Emergency Medicine, University of Pittsburgh School of Medicine, Suite 10028 Forbes Tower, Pittsburgh, PA, 15260, USA;3. Department of Critical Care Medicine & Department of Emergency Medicine, University of Pittsburgh School of Medicine, 637 Scaife Hall, 3550 Terrace Street, Pittsburgh, PA, 15261, USA;1. Department of Biotechnology, College of Science, University of Tehran, Tehran, Iran;2. Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran;3. Kawsar Genomics and Biotech Center, Tehran, Iran;1. Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India;2. Department of Experimental and Clinical Medicine “G Salvatore”, University of Catanzaro Magna Graecia, Catanzaro 88100, Italy;1. The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel;2. Soroka Medical Center, Beer Sheva, Israel |
| Abstract: | Microsomal membrane preparations of cauliflower inflorescences and mung bean hypocotyls possess duroquinone (DQ)-stimulated NADH oxidase activities at rates of 1–10 nmol NADH · min? · mg?. These redox reaction are associated with the endoplasmic reticulum (ER) and the plasma membrane (PM) as shown by the distributions of marker enzymes in sucrose gradients. The NADH oxidase thus partially cosediments with a specific blue light (or ascorbate) reducible b type cytochrome of the PM.Cauliflower membranes are further purified by means of an aqueous polymer two phase method. The NADH oxidase in this presumptive PM fraction is to some extent stimulated by Triton X-100 and insensitive to KCN (1 mM) or quinacrine (0.4 mM). Kinetics for DQ stimulation showed a biphasic saturation curve. These membranes also have a high FeCN reduction capacity induced by NADH but insensitive to DQ.No evidence could be found in the present study for the involvement of the specific b type cytochrome in the NADH dehydrogenase system. |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ | |