Glycine(redirected from L-glycine)
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glycine(glī`sēn), organic compound, one of the 20 amino acidsamino acid
, any one of a class of simple organic compounds containing carbon, hydrogen, oxygen, nitrogen, and in certain cases sulfur. These compounds are the building blocks of proteins.
..... Click the link for more information. commonly found in animal proteins. Glycine is the only one of these amino acids that is not optically active, i.e., it does not have d- and l-stereoisomers. It is structurally the simplest of the α-amino acids, having merely a hydrogen atom for a side chain, and is thus very unreactive when incorporated into proteins. Nevertheless, in the free state glycine participates in several important reactions, including the biosynthesis of heme, an important constituent of hemoglobinhemoglobin
, respiratory protein found in the red blood cells (erythrocytes) of all vertebrates and some invertebrates. A hemoglobin molecule is composed of a protein group, known as globin, and four heme groups, each associated with an iron atom.
..... Click the link for more information. , and the biosyntheses of serineserine
, organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein.
..... Click the link for more information. (another amino acid), purinespurine,
type of organic base found in the nucleotides and nucleic acids of plant and animal tissue. The German chemist Emil Fischer did much of the basic work on purines and introduced the term into the chemical literature in the early 20th cent.
..... Click the link for more information. (constituents of genetic material), and glutathione (a coenzymecoenzyme
, any one of a group of relatively small organic molecules required for the catalytic function of certain enzymes. A coenzyme may either be attached by covalent bonds to a particular enzyme or exist freely in solution, but in either case it participates intimately in
..... Click the link for more information. ). Defects of glycine metabolism are very rare. The amino acid is not essential to the diet since it can be made from other substances in the body. Glycine was the first amino acid to be isolated from a protein, in this case gelatin, and has been found in the halo of a comet, Wild 2.
(also called aminoacetic acid or glycocoll), the simplest acyclic amino acid, H2NCH2COOH; colorless crystals. Melting point, 232°-236° C (with decomposition); density, 1.595 g/cm3 (15° C). Its solubility in water at 25° C is 25 g per 100 g; it is insoluble in absolute ethanol and ether. It forms salts with acids and bases and forms complexes with many cations. Internal salts of N-trialkyl-substituted glycines are called betaines.
Glycine is a component of most plant and animal proteins. It is produced by hydrolysis of gelatin or silk fibroin. It can be synthesized from monochloroacetic acid and ammonia. The biological importance of glycine is due partly to its involvement in the synthesis of proteins and in the biosynthesis of many physiologically active compounds (glutathione, hippuric and glycocholic acids, and porphyrins). Glycine is used in preparing buffer solutions, for the synthesis of hippuric and aminohippuric acids, and in peptide synthesis.
In photography the name “glycin” is used for p-hydroxyphenylaminoacetic acid (hydroxyphenylglycine), HO—C6H4—NHCH2COOH; colorless crystals that are soluble in acids and alkalies but only slightly soluble in water and ethanol. Melting point, 245°-247° C (with decomposition). This acid is produced from monochloroacetic acid and p-aminophenol and is used as a developer.
(soybean), a genus of herbaceous plants of the family Leguminosae. There are several dozen species (according to other data, ten species), distributed predominantly in tropical countries having a humid climate. Cultivated species are G. hispida (or G. max), which is grown on all continents, and G. javanica, which is raised in Australia as a pasture plant. The wild species G. ussuriensis grows in the Soviet Far East.
Soybean plants are erect, twining, or creeping. The pinnate leaves are composed of three or, less frequently, five or six leaflets; there are small stipules. The white, violet, or red flowers are in axillary racemose inflorescences; in some species the flowers are solitary. The fruit is a linear or ensiform pod, or bean; the seeds are rounded, elongated, or flattened.
The common soybean (G. hispida) is divided into four subspecies: Korean (G. korajensis ssp.), Manchurian (G. manshurica ssp., which includes almost all varieties cultivated in the USSR), Chinese (G. chinensis ssp.), and Indian (G. indica ssp.) soybeans. It is believed to be a domesticated form of G. ussuriensis. An annual spring plant with a taproot system, the common soybean forms an erect shrub measuring 0.2–2 m in height. The leaves consist of three to five leaflets, and the inflorescence is made up of two to 25 flowers. The bean, which ranges from light colored to almost black, contains two or three (less commonly, one or four) seeds that are generally light in coloration. One thousand seeds weigh from 60 to 425 g. The plant is photophilic and hygrophytic, especially after flowering, but it can tolerate a brief drought. It grows well in all types of soil, except acid soils, waterlogged soils, or solonetzes. It consumes a great deal of nitrogen and phosphorus.
The common soybean is a culinary, industrial, forage, and green-manure crop. The seeds contain 24–45 percent protein, 20–32 percent carbohydrates, and 13–37 percent fat; they contain several vitamins, including vitamins D1, B, and E. The protein in soybeans is similar to animal protein in amino-acid composition. The seeds and immature beans are used as food. Milk, cottage cheese, and various confectioneries are prepared from soybean flour, as are many mixed feeds. The oil is used in the production of margarine and shortening; the refined oil is used as food. The seeds are raw material for many types of industrial products, including artificial fibers, plastics, glue, lacquers, paints, and soap; they also constitute the principal raw material for the production of synthetic and artificial food products. The green mass, hay, grass meal, oil cake, and groats are fed to cattle.
The common soybean is native to China, where it was first cultivated 5,000 years before the Common Era. Its cultivation spread to the countries of South and Southeast Asia. In the late 18th century the soybean was imported into Europe (France, Italy, Germany). It was first cultivated in the USA in the 19th century and in European Russia shortly before the turn of the 20th century. Worldwide plantings of soybean occupied 16 million hectares (ha) in 1948–52, 28.3 million ha in 1961–65, 35.8 million ha in 1970, and 44.5 million ha in 1974. (In 1974 soybeans occupied 21.1 million ha in the USA and 14.3 million ha in China.) The gross seed harvest in 1974 was 56.8 million tons (33.6 million tons in the USA, 11.9 million tons in China); the average seed yield was 12.8 quintals/ha.
In 1974 soybean plantings in the USSR were concentrated in the Far East, the Ukraine, the Northern Caucasus, Georgia, and Moldavia and occupied 850,000 ha. The gross seed harvest was 375,000 tons; the average yield was 4.41 quintals/ha (under the best farming conditions, up to 40 quintals/ha). The best varieties are Saliut 216, Amurskaia 41, Primorskaia 529, and VNIIMK 9186.
Soybeans are grown alone or in mixed plantings with corn and sorghum (for green mass, silage, and hay). The following doses of fertilizer are effective: 40 tons/ha of manure and 45–60 kg/ha of P2O5 or 110–150 kg/ha NPK. The fertilizer is applied at sowing and in supplementary feedings. Wide-row sowing (45 cm between rows) or two-line drilling (51 cm between rows) is used. The seeds are sown at a rate of 35–140 kg/ha and at a depth of 4–7 cm. The crop is harvested when the seed is completely mature; soybeans raised for green mass are harvested when the pods are formed. Pests include the moths Chloridea dipsácea and Laspeyresia glienivorella, the beetle Paraluperodes suturalis, and the pod borer. Diseases are bacteriosis, fusarial wilt, and sclerotiniose.
REFERENCESEnken, V. B. Soia. Moscow, 1959.
Gordienko, V. A., and I. I. Libershtein. Kladovaia belka. Moscow, 1969.
Sistema agrotekhnicheskikh meropriiatii po vozdelyvaniiu soi v Amurskoi oblasti. Blagoveshchensk, 1970.
Soya. Edited by V. B. Enken. Moscow, 1970. (Translated from English.)
Babich, A. A. Soia na korm. Moscow, 1974.
V. F. KUZIN