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An organism living in a state of commensalism.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



an organism that lives with an organism of a different species (permanently or temporarily); the commensal benefits from the association and does not injure the other organism. This association is called commensalism.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
The paper urged that "future research should aim to determine the frequency of these agonistic events and their cost to beaver survival and reproductive success, to determine if this relationship is really a commensal one or some integration of strong positive and negative effects".
Virulence scores of pneumonia isolates (5 [3-7]) were significantly higher than those of commensal isolates (3 [1-5]; p<0.0001) but not different from those of the bacteremia isolates (4 [2-7]; p = 0.3).
Soluble fiber is not digestible in the upper bowel and is thereby provided to resident commensal bacteria lower in the bowel.
Microbial growth of commensal organisms was detected on 13/15 (86.66 %) brushes tested in this study majority being streptococci along with E.
epidermidis is a common commensal bacterium of the skin, whereas Staphylococcus aureus is a human pathogen.
Interestingly, LTA from skin commensal bacteria can also directly influence MC activation by promoting their antimicrobial activity against vaccinia virus by means of production of cathelicidin [21].
Commensal Escherichia coli isolates are phylogenetically distributed among geographically distinct human populations.
One key factor in determining whether a host can maintain healthy gut microbiota communities is the ability to maintain colonization resistance, the process by which the host's commensal gut bacteria prevent pathogenic bacteria from colonizing or expanding in the GI tract (12).
acnes is a commensal bacterium on healthy skin seems to muddy the picture, until one also recognizes that there are different strains of P.
In birds of prey, white storks (Ciconia ciconia), and some waterfowl (Anatidae, Pelecanidae) species, mycoplasmas occur commonly and seem to be apathogenic or commensal and most likely belong to the physiologic microbial flora of the respiratory tract.
The study showed a difference in the commensal bacterial flora of the migraine patients from the control population.
Commensal Salmonella live in the gastrointestinal tract of a food animal without making it sick.