Modulation of Chlorophyll b Biosynthesis and Photosynthesis by Overexpression of Chlorophyllide a Oxygenase (CAO) in Tobacco
نویسندگان
چکیده
Chlorophyll (Chl) b is synthesized by oxidation of a methyl group on the B ring of the porphyrin molecule to a formyl group by chlorophyllide (Chlide) a oxygenase (CAO). The overexpression of Arabidopsis thaliana full length CAO (AtCAO) in tobacco (Nicotiana tabacum) resulted in an increased Chl synthesis and a decreased Chl a/b ratio in low-light-grown (LL) as well as in high-light-grown (HL) tobacco plants, where the effect was more pronounced. In HL-plants, increased [Chl b] resulted in efficient capture of solar energy and enhanced (40%–80%) electron transport rates at both limiting and saturating light intensities.
منابع مشابه
Light intensity-dependent modulation of chlorophyll b biosynthesis and photosynthesis by overexpression of chlorophyllide a oxygenase in tobacco.
Chlorophyll b is synthesized by the oxidation of a methyl group on the B ring of a tetrapyrrole molecule to a formyl group by chlorophyllide a oxygenase (CAO). The full-length CAO from Arabidopsis (Arabidopsis thaliana) was overexpressed in tobacco (Nicotiana tabacum) that grows well at light intensities much higher than those tolerated by Arabidopsis. This resulted in an increased synthesis of...
متن کاملLight Intensity-Dependent Modulation of Chlorophyll b Biosynthesis and Photosynthesis by Overexpression of Chlorophyllide a Oxygenase in Tobacco1[C][OA]
School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India (A.K.B., G.K.P., S.S.P., G., B.C.T.); International Center for Genetic Engineering and Biotechnology, New Delhi 110067, India (S.L., V.S.R.); and Department of Plant Biology, Department of Biochemistry and Center of Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 6180...
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