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Side chains are attached to the chlorin ring of the various chlorophyll molecules. Different side chains characterize each type of chlorophyll molecule, and alters the absorption spectrum of light. [10] [11] For instance, the only difference between chlorophyll a and chlorophyll b is that chlorophyll b has an aldehyde instead of a methyl group ...
Hydrolysis of chlorophyll a, b, d, and f during diagenesis in marine sediments, or during invertebrate feeding [7] releases phytol, which is then converted to phytane or pristane. Structure of chlorophyll a, with a side chain containing a phytyl group. Another possible source of phytane and pristane is archaeal ether lipids.
Appended to the chlorin ring are various side chains, usually including a long phytyl chain (C 20 H 39 O). The most widely distributed form in terrestrial plants is chlorophyll a. Chlorophyll a has methyl group in place of a formyl group in chlorophyll b. This difference affects the absorption spectrum, allowing plants to absorb a greater ...
Chlorophyll a, b, and d. Chlorophyll synthase [14] completes the biosynthesis of chlorophyll a by catalysing the reaction EC 2.5.1.62. chlorophyllide a + phytyl diphosphate chlorophyll a + diphosphate. This forms an ester of the carboxylic acid group in chlorophyllide a with the 20-carbon diterpene alcohol phytol.
Protochlorophyllide, [1] or monovinyl protochlorophyllide, is an intermediate in the biosynthesis of chlorophyll a. It lacks the phytol side-chain of chlorophyll and the reduced pyrrole in ring D. [2] Protochlorophyllide is highly fluorescent; mutants that accumulate it glow red if irradiated with blue light. [3]
Cyclobuxine is generally considered mildly toxic to humans. However, for animals (cats, dogs and especially horses), it is estimated to be highly toxic and can even be fatal. The (registered) lethal dose of cyclobuxine (leaves up to 1% dry weight) is 0.1 g/kg for dogs and 750 g leaves or levels approaching 0.15% of the body weight for horses. [26]
Pheophytin a, i.e. chlorophyll a without the Mg 2+ ion.. Pheophytin or phaeophytin is a chemical compound that serves as the first electron carrier intermediate in the electron transfer pathway of Photosystem II (PS II) in plants, and the type II photosynthetic reaction center (RC P870) found in purple bacteria.
The light-harvesting complex (or antenna complex; LH or LHC) is an array of protein and chlorophyll molecules embedded in the thylakoid membrane of plants and cyanobacteria, which transfer light energy to one chlorophyll a molecule at the reaction center of a photosystem. The antenna pigments are predominantly chlorophyll b, xanthophylls, and ...