High-Energy Compounds

natural compounds that contain energy-rich bonds.

High-energy compounds are present in all living cells, participating in the processes of energy accumulation and conversion. The compounds are represented mainly by adenosine triphosphate (ATP) and substances capable of ATP formation in enzyme reactions chiefly involving the transfer of phosphate groups. All known high-energy compounds contain either a phosphoryl group () or an acyl group

and are described by the formula

where X is an atom of nitrogen, oxygen, sulfur, or carbon and Y is an atom of phosphorus or carbon. The reactivity of high-energy compounds is related to the increased electrophilicity (affinity for electrons) of the Y atom, which accounts in particular for the high free energy of hydrolysis of the compounds (25.1-58.6 kilojoules per mole [6-14 kilocalories per mole]).

The high-energy compounds also include the nucleoside triphosphoric or diphosphoric acids, the pyrophosphoric and poly-phosphoric acids, phosphocreatine, phosphopyruvic acid, diphosphoglyceric acid, acetyl coenzyme A, succinyl coenzyme A, and the aminoacyl derivatives of adenylic and ribonucleic acids. The compounds are interrelated by their enzyme reactions involving the transfer of phosphoryl groups, in which ATP, a coenzyme in many enzymic reactions, is usually an intermediate product. The overall biological importance of ATP and related high-energy compounds is a function of their central position as links between sources of energy and metabolic processes. They make possible the performance of various types of work, and they play an important role in photosynthesis, bioluminescence, and the synthesis of proteins, fats, carbohydrates, nucleic acids, and other natural compounds.

High-energy compounds should be distinguished from phosphoryl and acyl compounds, which do not contain energy-rich bonds and are therefore incapable of ATP formation in transfer reactions involving phosphoryl and acyl groups (nucleoside monophosphoric acids, nucleic acids, phosphosaccharrides, phospholipides). However, the oxidation of some of these compounds may result in the formation of high-energy compounds.

REFERENCE

Skulachev, V. P. Akkumuliatsiia energii v kletke. Moscow, 1969.

V. P. SKULACHEV

high-energy compounds

high-en·er·gy com·pounds

classically, a group of phosphoric esters whose hydrolysis takes place with a standard free-energy change of -5 to -15 kcal/mol (or -20 to -63 kJ/mol), in contrast to -1 to -4 kcal/mol (or -4 to -17 kJ/mol) for simple phosphoric esters such as glucose 6-phosphate or α-glycerophosphates, and are thus capable of driving energy-consuming reactions in living cells or reconstituted cell-free systems; adenosine 5'-triphosphate, with respect to the β- and γ-phosphates, is the best known and is regarded as the immediate energy source for most metabolic syntheses. Other examples include acid anhydrides, phosphoric esters of enols, phosphamic acid (R-NH-PO₃H₂) derivatives, acyl thioesters (for example, of coenzyme A), sulfonium compounds (R₃-S⁺), and aminoacyl esters of ribosyl moieties.
See also: high-energy phosphates.

high-en·er·gy com·pounds

(hī-en'ĕr-jē kom'powndz) Classically, a group of phosphoric esters the hydrolysis of which takes place with a standard free energy change of -5 to -15 kcal/mol (or -20 to -63 kJ/mol) (in contrast to -1 to -4 kcal/mol, or -4 to -17 kJ/mol) for simple phosphoric esters like glucose 6-phosphate or α-glycerophosphates, thus being capable of driving energy-consuming reactions in living cells or reconstituted cell-free systems; adenosine 5'-triphosphate, with respect to the β- and γ-phosphates, is the best known and is regarded as the immediate energy source for most metabolic syntheses. Other examples include acid anhydrides, phosphoric esters ofenols, phosphamic acid (R-NH-PO₃H₂) derivatives, acyl thioesters (e.g., of coenzyme A), sulfonium compounds (R₃-S⁺), and aminoacyl esters of ribosyl moieties.
See also: high-energy phosphates

单词	high-energy compounds
释义	High-Energy Compounds High-Energy Compounds natural compounds that contain energy-rich bonds. High-energy compounds are present in all living cells, participating in the processes of energy accumulation and conversion. The compounds are represented mainly by adenosine triphosphate (ATP) and substances capable of ATP formation in enzyme reactions chiefly involving the transfer of phosphate groups. All known high-energy compounds contain either a phosphoryl group () or an acyl group and are described by the formula where X is an atom of nitrogen, oxygen, sulfur, or carbon and Y is an atom of phosphorus or carbon. The reactivity of high-energy compounds is related to the increased electrophilicity (affinity for electrons) of the Y atom, which accounts in particular for the high free energy of hydrolysis of the compounds (25.1-58.6 kilojoules per mole [6-14 kilocalories per mole]). The high-energy compounds also include the nucleoside triphosphoric or diphosphoric acids, the pyrophosphoric and poly-phosphoric acids, phosphocreatine, phosphopyruvic acid, diphosphoglyceric acid, acetyl coenzyme A, succinyl coenzyme A, and the aminoacyl derivatives of adenylic and ribonucleic acids. The compounds are interrelated by their enzyme reactions involving the transfer of phosphoryl groups, in which ATP, a coenzyme in many enzymic reactions, is usually an intermediate product. The overall biological importance of ATP and related high-energy compounds is a function of their central position as links between sources of energy and metabolic processes. They make possible the performance of various types of work, and they play an important role in photosynthesis, bioluminescence, and the synthesis of proteins, fats, carbohydrates, nucleic acids, and other natural compounds. High-energy compounds should be distinguished from phosphoryl and acyl compounds, which do not contain energy-rich bonds and are therefore incapable of ATP formation in transfer reactions involving phosphoryl and acyl groups (nucleoside monophosphoric acids, nucleic acids, phosphosaccharrides, phospholipides). However, the oxidation of some of these compounds may result in the formation of high-energy compounds. REFERENCE Skulachev, V. P. Akkumuliatsiia energii v kletke. Moscow, 1969. V. P. SKULACHEV high-energy compounds high-en·er·gy com·pounds classically, a group of phosphoric esters whose hydrolysis takes place with a standard free-energy change of -5 to -15 kcal/mol (or -20 to -63 kJ/mol), in contrast to -1 to -4 kcal/mol (or -4 to -17 kJ/mol) for simple phosphoric esters such as glucose 6-phosphate or α-glycerophosphates, and are thus capable of driving energy-consuming reactions in living cells or reconstituted cell-free systems; adenosine 5'-triphosphate, with respect to the β- and γ-phosphates, is the best known and is regarded as the immediate energy source for most metabolic syntheses. Other examples include acid anhydrides, phosphoric esters of enols, phosphamic acid (R-NH-PO₃H₂) derivatives, acyl thioesters (for example, of coenzyme A), sulfonium compounds (R₃-S⁺), and aminoacyl esters of ribosyl moieties. See also: high-energy phosphates. high-en·er·gy com·pounds (hī-en'ĕr-jē kom'powndz) Classically, a group of phosphoric esters the hydrolysis of which takes place with a standard free energy change of -5 to -15 kcal/mol (or -20 to -63 kJ/mol) (in contrast to -1 to -4 kcal/mol, or -4 to -17 kJ/mol) for simple phosphoric esters like glucose 6-phosphate or α-glycerophosphates, thus being capable of driving energy-consuming reactions in living cells or reconstituted cell-free systems; adenosine 5'-triphosphate, with respect to the β- and γ-phosphates, is the best known and is regarded as the immediate energy source for most metabolic syntheses. Other examples include acid anhydrides, phosphoric esters ofenols, phosphamic acid (R-NH-PO₃H₂) derivatives, acyl thioesters (e.g., of coenzyme A), sulfonium compounds (R₃-S⁺), and aminoacyl esters of ribosyl moieties. See also: high-energy phosphates
随便看	mental virus mental ward mental weakness mental welfare commission mental wellness mentana menta piperita mentastics mentat mentat (dune) mentation mentations mentats mentawai mentawei mentawi mentax mentch mentee menteith menten menten, maud leonora menteri negara lingkungan hidup mentes mentha