Ligand

Definition: Ligand

Ligand

Noun

1. An atom or molecule or radical or ion that forms a complex around a central atom.

Crosswords: Ligand

Specialty definitions using "ligand": Activated-Leukocyte Cell Adhesion Molecule, Affinity Chromatography, Antigens, CD80 ♦ C52 ligand, CD40 Ligand ♦ Intercellular Adhesion Molecule-1 ♦ Lymphocyte Function-Associated Antigen-1 ♦ Neuregulin-1, neuro-immunophilin ligand ♦ Receptor, Epidermal Growth Factor, Receptors, Aryl Hydrocarbon, Receptors, Mineralocorticoid, Receptors, sigma, Receptors, Transferrin, Retinol-Binding Proteins ♦ Stem Cell Factor ♦ triplex-forming oligonucleotide. (references)

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Specialty Definition: Ligand

(From Wikipedia, the free Encyclopedia)

In chemistry, a ligand is an atom, ion or functional group that is bonded to one or more central (usually metal) ion(s) forming a complex.

The central atom or group of atoms will have a positive charge, and the ligands will bond by compensating that charge with their own negative charge or characteristics. As the central atom has a specific charge, it has a maximum potential number of ligands (as each must donate at least one electron into the charge compensation equation) that it can bond to. These ligands will also arrange themselves into a certain arrangement around the central atom. If a single ligand bonds to more than one of these bonding sites on the central atom, then it is said to be bidentate (three=tridentate, etc)

Ligand arrangements

These are named and described as if the central atom is in the middle of a polyhedron, and the corners of that shape are the locations of the ligands. For example, a complex with four, regularly distributed ligands would be described as tetrahedral.

Aside from the regular polyhedra, there are special descriptions, such as pyramidal (four ligands equally distributed in a plane, and one ligand normal to this plane).

Polydentate ligands

Ligands which only bond to the central metal atom/ion through one site are termed monodentate. Some ligand molecules are able to bind to the metal ion through multiple sites, due to having free lone pairs on more than one atom, these are called polydentate. EDTA is an example of a polydentate ligand - it is able to bond through 6 sites, completely surrounding the ion. Polydentate ligands tend to be very stable, as it is necessary to break all of their bonds to the central atom for them to be displaced.

Common ligands

F^-
Cl^-
Br^-
I^-
CO
RC:CR - compounds with double carbon bonds
Benzene
Cryptates
Crown ethers
OH^-

In biochemistry, a ligand will refer to a small molecule that binds to a larger macromolecule, whether or not the ligand actually binds at a metal site or not. This is probably a carryover from the large number of binding studies on oxygen transport proteins, such as hemoglobin, where the ligand indeed did bind at a metal site, an expansion of the term to a more general case of binding.

Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Ligand."

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Commercial Usage: Ligand

Domain	Title
References	Ligand Pharmaceutical Incorporated: International Competitive Benchmarks and Financial Gap Analysis (reference) (more reference examples)

Books	Market Guide / ProVestor Plus Company Report for Ligand Pharmaceuticals - LGND [DOWNLOAD: PDF] (reference) RNA - Ligand Interactions, Part A (Methods in Enzymology, Volume 317) (reference) Structure-Based Ligand Design (Methods and Principles in Medicinal Chemistry, Vol 6) (reference) (more book examples)

Periodicals	Ligand Essay (reference) (more periodical examples)
Source: compiled by the editor from various references; see credits.

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Non-Fiction Usage: Ligand

Subject	Topic	Quote
Health		An interesting and unexpected development of Gustafsson's work in locating "orphan" receptors--receptors for which no known ligand has been identified--was the discovery of an ER in the prostate. (references)
Source: compiled by the editor from ICON Group International, Inc.; see credits.

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Usage Frequency: Ligand

"Ligand" is generally used as a noun (singular) -- approximately 96.94% of the time. "Ligand" is used about 98 times out of a sample of 100 million words spoken or written in English. Its rank is based on over 700,000 words used in the English language. Some parts-of-speech are not covered due to the samples used by the British National Corpus. (note: percents less than one-hundredth of one percent have been omitted)

Parts of Speech	Percent	Usage per 100 Million Words	Rank in English
Noun (singular)	96.94%	95	33,629
Lexical Verb (base form)	2.04%	2	245,945
Lexical Verb (infinitive)	1.02%	1	339,140
Total	100.00%	98	N/A

Source: compiled by the editor from several corpora; see credits.

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Usage in Company Names: Ligand

Country	Name
USA	Ligand Pharmaceutical Incorporated
	(more examples...)

Source: compiled by the editor from Icon Group International, Inc.

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Expression: Ligand

Expressions using "ligand": C52 ligand ♦ CD40 Ligand. Additional references.
Hyphenated Usage
	Beginning with "ligand": ligand-based, ligand-binding, ligand-gated, ligand-induced, ligand-integrin, ligand-ligand, ligand-metal, ligand-receptor, ligand-to-metal.
	Ending with "ligand": metal-ligand.
Source: compiled by the editor from various references; see credits.

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Frequency of Internet Keywords: Ligand

The following statistics estimate the number of searches per day across the major English-language search engines as identified by various trade publications. Hyperlinks lead to commercial use of the expression at Amazon.com.

Expression	Frequency per Day
ligand	68
ligand pharmaceutical	40
animation channel ligand	4
definition ligand	4
binding ligand	3
ligand pharmaceutical inc	3
ligand pharm	3
ligand receptor	3
assay clinical journal ligand	2
Source: compiled by the editor from various references; see credits.

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Modern Translations: Ligand

Language		Translations for "ligand"; alternative meanings/domain in parentheses.
Danish		ligand. (various references)

Dutch		ligand. (various references)

Finnish		ligandikromatografia (ligand-exchange chromatography), selektiivinen välitysaine (selective ligand), selektiivinen ligandi (selective ligand). (various references)

French		ligand, coordinat. (various references)

German		Ligand. (various references)

Greek		χρωματογραφία σχηματισμού συμπλόκων (ligand-exchange chromatography), χρωματογραφία ανταλλαγής συμπλόκων (ligand-exchange chromatography), δοκιμασία πρόσδεσης του συνδέτη (ligand binding assay). (various references)

Hungarian		ligandum, kötött atomcsoport, kötött atom. (various references)

Italian		legante (binder, binding, binding agent, bond, bonding, bonding agent, cement, imperative, ligating, matrix, paint vehicle, urgent, vehicle), vincolante. (various references)

Pig Latin		igandlay

Portuguese		ligando (calling). (various references)

Spanish		ligando. (various references)

Swedish		ligandkromatografi (ligand-exchange chromatography), selektiv ligand (selective ligand). (various references)
Source: compiled by the editor from various translation references.

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Derivations: Ligand

Derivations
	Words beginning with "ligand": ligands. (additional references)
Source: compiled by the editor, based on several corpora (additional references).

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Rhyming with "Ligand"

# of Phoneme Matches	Pronunciation	Word(s) rhyming with "ligand" (pronounced li"gund)
4	-g u n d	bargained.
3	-u n d	abandoned, aforementioned, aland, almond, apportioned, auctioned, auditioned, awakened, beckoned, blackened, bludgeoned, brightened, broadened, burdened, burgeoned, buttoned, captioned, cautioned, championed, chastened, cheapened, chickened, christened, commissioned, conditioned, cordoned, cottoned, cushioned, dampened, darkened, decommissioned, deepened, destined, determined, diamond, dimensioned, disciplined, disheartened, disillusioned, dockland, Eland, emblazoned, emboldened, engined, enlightened, enlivened, envisioned, errand, evened, examined, fashioned, fastened, fattened, flattened, frightened, functioned, gardened, Garland, garrisoned, glistened, happened, hardened, hastened, heartened, heightened, Highland, Holland, husband, illumined, imagined, impassioned, imprisoned, island, jettisoned, leavened, legend, lengthened, lessened, lightened, likened, listened, livened, loosened, malfunctioned, margined, mentioned, millisecond, moistened, moribund, motioned, nanosecond, Norland, occasioned, opened, optioned, orphaned, Osmund, overburdened, pardoned, partitioned, petitioned, poisoned, positioned, predestined, predetermined, prisoned, proportioned, propositioned, questioned, quickened, rationed, reasoned, reawakened, rechristened, reckoned, reconditioned, reexamined, reopened, repositioned, requisitioned, Reverend, ripened, ruined, saddened, sanctioned, seasoned, second, sectioned, sharpened, Shetland, shortened, sickened, siphoned, slackened, softened, soland, stationed, steepened, stiffened, stipend, straightened, strengthened, summoned, sweetened, thickened, thousand, threatened, tightened, toughened, unburdened, unbuttoned, undetermined, unenlightened, unmentioned, unopened, unquestioned, unsanctioned, upland, vacationed, weakened, widened, wizened, worsened.
Source: compiled by the editor (additional references); see credits.

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Anagrams: Ligand

Scrabble® Enable2K-Verified Anagrams
	Direct Anagrams: lading.
	Words within the letters "a-d-g-i-l-n"
	-1 letter: algid, algin, align, gland, liang, ligan, linga, nidal.
	-2 letters: agin, anil, dang, dial, ding, gadi, gain, gild, glad, glia, laid, lain, land, lang, ling, nail.
	-3 letters: aid, ail, ain, and, ani, dag, dal, dig, din, gad, gal, gan, gid, gin, lad, lag, lid, lin, nag, nil.
	-4 letters: ad, ag, ai, al, an, id, in.
	Words containing the letters "a-d-g-i-l-n"
	+1 letter: addling, aligned, balding, darling, dealing, dialing, gliadin, ladings, ladling, landing, languid, larding, lauding, leading, ligands, loading.
	+2 letters: alluding, blindage, candling, cladding, cradling, dabbling, daddling, daggling, dallying, dandling, dangling, dappling, daringly, darkling, darlings, dartling, dawdling, dazzling, dealings, delating, delaying, diagonal, dialings, dialling, dilating, dragline, drawling, finagled, gladding, gliadine, gliadins, gonadial, gonidial, handling, highland, ladening, landings, leadings, loadings, maligned, medaling, paddling, pedaling, pleading, raddling, saddling, sandling, scalding, signaled, unlading, waddling, windgall.
Source: compiled by the editor from various references; see credits. SCRABBLE® is a registered trademark. All intellectual property rights in and to the game are owned in the U.S.A and Canada by Hasbro Inc., and throughout the rest of the world by J.W. Spear & Sons Limited of Maidenhead, Berkshire, England, a subsidiary of Mattel Inc. Mattel and Spear are not affiliated with Hasbro.