Putative Mutation Mechanism and Light Responses of a Protochlorophyllide Oxidoreductase-Less Barley Mutant NYB
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چکیده
منابع مشابه
A chlorophyll-less barley mutant "NYB" is insensitive to water stress.
"NYB" is a chlorophyll-less barley mutant, which grows relatively slow and unhealthily. The effects of water stress on photosystem II (PSII) of NYB and its wild type (WT) were investigated. Unexpected results indicated that the mutant was more resistant to water stress, because: PSII core proteins D1, D2 and LHCII declined more in WT than in NYB under water stress, and the corresponding psbA, p...
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The addition of two electrons and two protons to the C17=C18 bond in protochlorophyllide is catalyzed by a light-dependent enzyme relying on NADPH as electron donor, and by a light-independent enzyme bearing a (Cys)3Asp-ligated [4Fe-4S] cluster which is reduced by cytoplasmic electron donors in an ATP-dependent manner and then functions as electron donor to protochlorophyllide. The precise sequ...
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The unique light-driven enzyme protochlorophyllide oxidoreductase (POR) is an important model system for understanding how light energy can be harnessed to power enzyme reactions. The ultrafast photochemical processes, essential for capturing the excitation energy to drive the subsequent hydride- and proton-transfer chemistry, have so far proven difficult to detect. We have used a combination o...
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Hydride transfer plays a crucial role in a wide range of biological systems. However, its mode of action (concerted or stepwise) is still under debate. Light-dependent NADPH: protochlorophyllide oxidoreductase (POR) catalyzes the stereospecific trans addition of a hydride anion and a proton across the C17 -C18 double bond of protochlorophyllide. Time-resolved absorption and emission spectroscop...
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ژورنال
عنوان ژورنال: Plant and Cell Physiology
سال: 2010
ISSN: 1471-9053,0032-0781
DOI: 10.1093/pcp/pcq097