Growth arrest of Synechocystis sp. PCC6803 by superoxide generated from heterologously expressed Rhodobacter sphaeroides chlorophyllide a reductase.
The photosynthetic growth of Synechocystis sp. PCC6803 ceased upon expression of Rhodobacter sphaeroides chlorophyllide a reductase (COR). However, an increase in cytosolic superoxide dismutase level in the recombinant Synechocystis sp. PCC6803 completely reversed the growth cessation. This demonstrates that COR generates superoxide in Synechocystis sp. PCC6803. Considering the dissolved oxygen (DO) level suitable for COR, the intracellular DO of this oxygenic photosynthetic cell appears to be low enough to support COR-mediated superoxide generation. The growth arrest of Synechocystis sp. PCC6803 by COR may give an insight into the evolutionary path from bacteriochlorophyll a biosynthetic pathway to chlorophyll a, which bypasses COR reaction.
Kim
Eui-Jin
EJ
Department of Life Science, Sogang University, Seoul, Republic of Korea.
Kim
Ju-Sim
JS
Rhee
Hae Jin
HJ
Lee
Jeong K
JK
D019143:Evolution, Molecular; D044925:Oxidoreductases Acting on CH-CH Group Donors / Q000235:genetics / Q000378:metabolism*; D012242:Rhodobacter sphaeroides / Q000201:enzymology* / Q000235:genetics; D013481:Superoxides / Q000378:metabolism*; D046939:Synechocystis / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development*
D013481:Superoxides; D044925:Oxidoreductases Acting on CH-CH Group Donors