Metal and Serine Proteases in the Crude Photosystem Ⅱ Particles from a Diatom,Chaetoceros Gracilis
We found that most of subunits in crude Photosystem Ⅱ particles (crude PSⅡ) from a marine centric diatom, Chaetoceros gracilis, were degraded during incubation for 18 h at 25 ℃ in the dark (Nagao et al, 2010). In this study, we attempted to suppress the protein degradation by addition of protease inhibitors to the crude PSⅡ during incubation for various times at 25 ℃ in the dark. When no proteases inhibitor added to the crude PSⅡ, fucoxanthin chlorophyll a/c-binding protein (FCP), especially upper subunits of FCP, were first degraded, followed by most of PSⅡ subunits. The degradation was slightly suppressed by a metal protease inhibitor, EDTA, or a serine protease inhibitor, PMSF, and the proteolysis activity of metal protease is slightly stronger than that of serine protease. On the other hand, the significant suppression was observed only by both EDTA and PMSF. These results suggest that the metal and serine proteases are associated with the crude PSⅡ and the primary target of the proteases is the upper subunits of FCP.
Chaetoceros gracilis Photosystem Ⅱ Protease Proteolysis
Ryo Nagao Eri Noguchi Tatsuya Tomo Isao Enami Masahiko Ikeuchi
Department of Life Sciences (Biology), Graduate School of Art and Sciences, University of Tokyo, Jap Department of Biology, Faculty of Science, Tokyo University of Science, Japan
国际会议
15th International Conference on Photosynthesis(第15届国际光合作用大会)
北京
英文
83-85
2010-08-22（万方平台首次上网日期，不代表论文的发表时间）