bond


bond
In chemistry, the force holding two neighboring atoms in place and resisting their separation; a b. is electrovalent if it consists of the attraction between oppositely charged groups, or covalent if it results from the sharing of one, two, or three pairs of electrons by the bonded atoms.
- acylmercaptan b. —CO—S—; a “high-energy” b. formed by the condensation of a carboxyl group (—COOH) and a mercaptan (or thiol) group (—SH); widely formed in the course of intermediary metabolism, notably in the oxidation of fats, where the —SH is part of coenzyme A and the —COOH is part of the fatty acid being oxidized.
- apolar b. hydrophobic interaction.
- conjugated double bonds two or more double b. separated by each single b..
- coordinate covalent b. SYN: semipolar b..
- disulfide b. a single b. between two sulfurs; specifically, the —S—S— link binding two peptide chains (or different parts of one peptide chain); also occurs as part of the molecule of the amino acid, cystine, and is important as a structural determinant in many peptide and protein molecules, e.g., keratin, insulin, and oxytocin. A symmetric disulfide is R—S—S—R; R′—S—S—R is a mixed or asymmetric disulfide.
- double b. a covalent b. resulting from the sharing of two pairs of electrons, e.g., H2C=CH2 (ethylene).
- electrostatic b. b. between atoms or groups carrying opposite charges (or, in some cases, partial charges). SYN: heteropolar b., salt bridge.
- energy-rich b. high-energy compounds, under compound.
- eupeptide b. a peptide b. between the α-carboxyl group of one amino acid and the α-amino group of another amino acid. Cf.:peptide b., isopeptide b..
- heteropolar b. SYN: electrostatic b..
- high energy phosphate b. high-energy phosphates, under phosphate.
- hydrogen b. a b. arising from the sharing of a hydrogen atom, covalently bound to a strongly electronegative element ( e.g., N or O), with another strongly electronegative element ( e.g., N, O, or a halogen). In substances of biologic importance, the most common hydrogen bonds are those in which H links N to O or N; such bonds link purines on one strand to pyrimidines on the other strand of nucleic acid s, thus maintaining double-stranded structures as in the Watson-Crick helix.
- hydrophobic b. hydrophobic interaction.
- isopeptide b. an amide linkage between a carboxyl group of one amino acid and an amino group of another amino acid in which at least one of these groups is not on the α-carbon of one of the amino acid s; for example, the b. between the glutamyl residue and the cysteinyl residue of glutathione. Cf.:peptide b., eupeptide b..
- noncovalent b. b. in which electrons are not shared between atoms; E.G., electrostatic b., hydrogen b..
- peptide b. the common link (—CO—NH—) between amino acid s in proteins, actually a substituted amide, formed by elimination of H2O between the —COOH of one amino acid and the H2N— of another. Cf.:eupeptide b., isopeptide b..
- semipolar b. a b. in which the two electrons shared by a pair of atoms belonged originally to only one of the atoms; often represented by a small arrow pointing toward the electron receiver; e.g., nitric acid, O(OH)N→O; phosphoric acid, (OH)3P→O. SYN: coordinate covalent b..
- single b. a covalent b. resulting from the sharing of one pair of electrons; e.g., H3C—CH3 (ethane).
- triple b. a covalent b. resulting from the sharing of three pairs of electrons; e.g., HCΞCH (acetylene).

* * *

bond 'bänd n an attractive force that holds together atoms, ions, or groups of atoms in a molecule or crystal usu. represented in formulas by a line
bond vb

* * *

(bond) 1. the linkage between two atoms or radicals of a chemical compound. 2. a mark used to indicate the number and attachment of the valences of an atom in constitutional formulas; it is represented by a pair of dots or a line between the atoms, e.g., HOH, HCCH or H:O:H, H:C:::C:H.

Medical dictionary. 2011.

Synonyms:

Look at other dictionaries:

  • bond — bond …   Dictionnaire des rimes

  • bond — 1 n 1 a: a usu. formal written agreement by which a person undertakes to perform a certain act (as appear in court or fulfill the obligations of a contract) or abstain from performing an act (as committing a crime) with the condition that failure …   Law dictionary

  • Bond — Bond, bonds, bonded, and bonding may refer to:Fiduciary bonds*Bond (finance), in finance, a debt security, issued by Issuer **Government bond, a bond issued by a national government ***Government bond register, a register of bonds issued by a… …   Wikipedia

  • bond — [ bɔ̃ ] n. m. • 1390; de bondir 1 ♦ Action de bondir, de s élever de terre par un mouvement brusque. ⇒ saut. D un bond, il franchit l obstacle. Les bonds d un danseur. Avancer par petits bonds. Le chien faisait des bonds de joie (⇒ gambader) .… …   Encyclopédie Universelle

  • Bond — steht für: ein verzinsliches Wertpapier eine durch Drahtbonden hergestellte Verbindung BOND e.V., Bund der Osteologen in Norddeutschland Bond (Band), ein britisch australisches Streichquartett BOND, einen Hersteller von Bibliothekssoftware Bond… …   Deutsch Wikipedia

  • Bond — (b[o^]nd), n. [The same word as band. Cf. {Band}, {Bend}.] 1. That which binds, ties, fastens, or confines, or by which anything is fastened or bound, as a cord, chain, etc.; a band; a ligament; a shackle or a manacle. [1913 Webster] Gnawing with …   The Collaborative International Dictionary of English

  • Bond — Saltar a navegación, búsqueda Este artículo trata sobre música. Para el personaje de ficción, véase James Bond. Información personal Origen …   Wikipedia Español

  • Bond — /bond/, n. 1. Carrie (nee Jacobs), 1862 1946, U.S. songwriter and author. 2. Julian, born 1940, U.S. civil rights leader and politician. * * * I In construction, the systematic arrangement of bricks or other building units (e.g., concrete blocks …   Universalium

  • BOND — Cette page d’homonymie répertorie les différents sujets et articles partageant un même nom …   Wikipédia en Français

  • bond — bond·ag·er; bond; bond·er·ize; bond·less; bond·maid; bond·man; bond·wom·an; vag·a·bond·age; vag·a·bond·ish; vag·a·bond·ism; vag·a·bond·ize; an·ti·bond·ing; eu·ro·bond; spun·bond·ed; bond·age; vag·a·bond; bond·a·ble; …   English syllables

  • bond — BOND. s. m. Le saut, le rejaillissement que fait un balon, une bale, ou autre chose semblable, lors qu elle tombe en terre, ou y est jettée. La bale n a point fait de bond. attendre la bale au bond. prendre la bale au bond. quand on ne prend la… …   Dictionnaire de l'Académie française