首页 | 本学科首页   官方微博 | 高级检索  
   检索      


Mechanism of Photoregulated Carotenogenesis in Rhodotorula minuta V. Photoinduction of 3-Hydroxy-3-Methyl Glutaryl Coenzyme A Reductase
Authors:Tada  Mikiro; Shiroishi  Masahide
Institution:Department of Agricultural Chemistry, Faculty of Agriculture, Okayama University Tsushima-naka, Okayama 700, Japan
Abstract:The effect of light on the activity of 3-hydroxy-3-methylglutarylCoenzyme A (HMG-CoA) reductase in Rhodotorula minuta was studiedin cell-free extracts prepared from cells grown under variouslight conditions. HMG-CoA reductase activity in cells grown under continuous illuminationwas higher than that in cells grown in the dark, and dependedon the light intensity used during incubation. The relationshipbetween activity A (nmol/mg-N/min)] and light intensity I(erg/cm2/sec)] was expressed by the equation A=0.72 log I$0.80. Illumination at –1.5?C followed by dark incubation at26?C resulted in a rapid increase in HMG-CoA reductase activityimmediately after the beginning of incubation. This photoinducedHMG-CoA reductase activity was regulated by the light dose andfollowed the Roscoe-Bunsen reciprocity law. When cycloheximide was added immediately after the beginningof incubation in the dark, the increase in HMG-CoA reductaseactivity was completely inhibited. The inhibitory effect ofcycloheximide, however, gradually decreased with the delay ofthe addition. On the basis of these results we have postulated that the photoregulationof carotenogenesis in Rh. minuta results from the photoregulationof HMG-CoA reductase synthesis. (Received November 7, 1981; Accepted March 19, 1982)
Keywords:
本文献已被 Oxford 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号