Synthesis and Degradation of Nitrate Reductase during the Cell Cycle of Chlorella Sorokiniana |
| |
| Authors: | Patricia J Velasco Rudolf Tischner Raymond C Huffaker and John R Whitaker |
| |
| Affiliation: | Department of Food Science and Technology and Plant Growth Laboratory, University of California, Davis, California 95616;Pflanzenphysiologisches Institut der Unviersität, Untere Karspüle 2, D-3400 Gottingen, Federal Republic of Germany |
| |
| Abstract: | Studies on the diurnal variations of nitrate reductase (NR) activity during the life cycle of synchronized Chlorella sorokiniana cells grown with a 7:5 light-dark cycle showed that the NADH:NR activity, as well as the NR partial activities NADH:cytochrome c reductase and reduced methyl viologen:NR, closely paralleled the appearance and disappearance of NR protein as shown by sodium dodecyl sulfate gel electrophoresis and immunoblots. Results of pulse-labeling experiments with 35S]methionine further confirmed that diurnal variations of the enzyme activities can be entirely accounted for by the concomitant synthesis and degradation of the NR protein. |
| |
| Keywords: | |
|
|
