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tr.v. ob·li·gat·ed, ob·li·gat·ing, ob·li·gates
1. To compel or constrain by a social, legal, or moral requirement. See Synonyms at force.
2. To cause to be grateful or indebted; oblige: We will always be obligated to you for your kindness.
3. To commit (money, for example) in order to fulfill an obligation.
adj. (-gĭt, -gāt′)
Able to exist or survive only in a particular environment or by assuming a particular role: an obligate parasite; an obligate anaerobe.
n. (-gĭt, -gāt′)
An obligate organism.

[Latin obligāre, obligāt-; see oblige.]

ob′li·ga·ble (-gə-bəl) adj.
ob′li·gate·ly adv.
ob′li·ga′tor n.


(Biology) biology in an obligate or necessary manner
References in periodicals archive ?
Given that tau hyperphosphorylation precedes aggregation, and tau aggregates are obligately phosphorylated in AD brain, phosphorylation has been suggested as a primary trigger for tau aggregation.
They are obligately dependent on the fungi they grow, though displaying great variation in their ecology (Mehdiabadi & Schultz 2010).
When a hypolimnion remains anoxic, obligately anaerobic prokaryotic populations, including Archaeal methanogens, presumably increase, but a lake that never has an oxygenated hypolimnion due to salt-induced stratification likely produces more methane because conditions that favor methanogen growth are persistent.
Individual variation in feeding habitat use by adult female green sea turtles (Chelonia mydas): are they obligately neritic herbivores?
Sorokin DY, Teske A, Robertson LA, Kuenen JG (1999) Anaerobic oxidation of thiosulfate to tetrathionate by obligately heterotrophic bacteria, belonging to the Pseudomonas stutzeri group.
Other microorganisms associated with kefir are the homofermentative strains Lactobacillus acidophilus and Lactobacillus kefirgranum, the obligately heterofermentative strains Lactobacillus kefir and Lactobacillus parakefir (103).
The taxonomy and natural history of ants of the genus Crematogaster Lund, 1831 (Crematogaster borneensis-group of the former subgenus Decacrema) obligately associated with myrmecophytic host-plants of the euphorb genus Macaranga are reviewed.
Cook GM, Rainey FA, Patel BKC & Morgan HW (1996) Characterization of a New Obligately Anaerobic Thermophile, Thermoanaerobacter wiegelii sp.
Bacteroides, which is a genus of gram-negative and an obligately anaerobic bacteria, possesses an effective barrier to hydrophobic molecules and therefore can metabolize hydrophobic amino acids including tyrosine and tryptophan as well as aromatic amino acids into phenols, indoles and their precursors (Smith and Macfarlane, 1998; Van der Meulen et al.
55,56) These compounds are diagenetic derivatives of photosynthetic pigments, isorenieratene and bacteriochlorophylls e, respectively, from obligately anaerobic green sulfur bacteria.
Brevibacteria are nonmotile, nonfastidous, chemoorganothrophic, obligately aerobic, rod-shaped, halotolerant (> 6.