ChlorinIn organic chemistry, chlorins are tetrapyrrole pigments that are partially hydrogenated porphyrins. The parent chlorin is an unstable compound which undergoes air oxidation to porphine. The name chlorin derives from chlorophyll. Chlorophylls are magnesium-containing chlorins and occur as photosynthetic pigments in chloroplasts. The term "chlorin" strictly speaking refers to only compounds with the same ring oxidation state as chlorophyll. Chlorins are excellent photosensitizing agents.
Photodynamic therapyPhotodynamic therapy (PDT) is a form of phototherapy involving light and a photosensitizing chemical substance, used in conjunction with molecular oxygen to elicit cell death (phototoxicity). PDT is popularly used in treating acne. It is used clinically to treat a wide range of medical conditions, including wet age-related macular degeneration, psoriasis, atherosclerosis and has shown some efficacy in anti-viral treatments, including herpes. It also treats malignant cancers including head and neck, lung, bladder and particular skin.
Chlorophyll aChlorophyll a is a specific form of chlorophyll used in oxygenic photosynthesis. It absorbs most energy from wavelengths of violet-blue and orange-red light, and it is a poor absorber of green and near-green portions of the spectrum. Chlorophyll does not reflect light but chlorophyll-containing tissues appear green because green light is diffusively reflected by structures like cell walls. This photosynthetic pigment is essential for photosynthesis in eukaryotes, cyanobacteria and prochlorophytes because of its role as primary electron donor in the electron transport chain.
BacteriochlorophyllBacteriochlorophylls (BChl) are photosynthetic pigments that occur in various phototrophic bacteria. They were discovered by C. B. van Niel in 1932. They are related to chlorophylls, which are the primary pigments in plants, algae, and cyanobacteria. Organisms that contain bacteriochlorophyll conduct photosynthesis to sustain their energy requirements, but the process is anoxygenic and does not produce oxygen as a byproduct. They use wavelengths of light not absorbed by plants or cyanobacteria.
ChlorophyllideChlorophyllide a and Chlorophyllide b are the biosynthetic precursors of chlorophyll a and chlorophyll b respectively. Their propionic acid groups are converted to phytyl esters by the enzyme chlorophyll synthase in the final step of the pathway. Thus the main interest in these chemical compounds has been in the study of chlorophyll biosynthesis in plants, algae and cyanobacteria. Chlorophyllide a is also an intermediate in the biosynthesis of bacteriochlorophylls. Chlorophyllide a, is a carboxylic acid (R=H).
CorrinCorrin is a heterocyclic compound. Although not known to exist on its own, the molecule is of interest as the parent macrocycle related to the cofactor and chromophore in vitamin B12. Its name reflects that it is the "core" of vitamin B12 (cobalamins). Compounds with a corrin core are known as "corrins". There are two chiral centres, which in natural compounds like cobalamin have the same stereochemistry. Vitamin B12 Upon deprotonation, the corrinoid ring is capable of binding cobalt.
SheepSheep (: sheep) or domestic sheep (Ovis aries) are a domesticated, ruminant mammal typically kept as livestock. Although the term sheep can apply to other species in the genus Ovis, in everyday usage it almost always refers to domesticated sheep. Like all ruminants, sheep are members of the order Artiodactyla, the even-toed ungulates. Numbering a little over one billion, domestic sheep are also the most numerous species of sheep. An adult female is referred to as a ewe (juː), an intact male as a ram, occasionally a tup, a castrated male as a wether, and a young sheep as a lamb.
TetrapyrroleTetrapyrroles are a class of chemical compounds that contain four pyrrole or pyrrole-like rings. The pyrrole/pyrrole derivatives are linked by (=(CH)- or -CH2- units), in either a linear or a cyclic fashion. Pyrroles are a five-atom ring with four carbon atoms and one nitrogen atom. Tetrapyrroles are common cofactors in biochemistry and their biosynthesis and degradation feature prominently in the chemistry of life. Some tetrapyrroles form the active core of compounds with crucial biochemical roles in living systems, such as hemoglobin and chlorophyll.
ChlorophyllChlorophyll (also chlorophyl) is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants. Its name is derived from the Greek words χλωρός , ("pale green") and φύλλον , ("leaf"). Chlorophyll allow plants to absorb energy from light. Chlorophylls absorb light most strongly in the blue portion of the electromagnetic spectrum as well as the red portion. Conversely, it is a poor absorber of green and near-green portions of the spectrum.
Chlorophyllide a reductaseChlorophyllide a reductase (), also known as COR, is an enzyme with systematic name bacteriochlorophyllide-a:ferredoxin 7,8-oxidoreductase. It catalyses the following chemical reaction chlorophyllide a + 2 reduced ferredoxin + ATP + H2O + 2 H+ 3-deacetyl 3-vinylbacteriochlorophyllide a + 2 oxidized ferredoxin + ADP + phosphate Chlorophyllide a.svg|Chlorophyllide ''a'' Bacteriochlorophyllide a.png|Bacteriochlorophyllide ''a'' (R=H).
