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Related to Bacteroids: Bacteroides fragilis, Fusobacterium



(1) Large branched cells of nodule-forming bacteria that are contained in nodules on the roots of leguminous plants (clover, alfalfa, and others). The origin of bacteroids is linked to the life cycle of the nodule-forming bacteria, and it occurs in all species. The young cells are rod-shaped. After penetrating into the root hair, they produce nodules and acquire the external appearance characteristic of bacteroids. Bacteroids apparently are more active in fixing atmospheric nitrogen than are young cells.

(2) Strictly anaerobic, gram-negative, highly polymorphic bacteria, which form neither spores nor capsules. They are usually nonmotile rods, as small as 2 microns. They are regularly found in the mouth, intestines, and genitalia of man. Many species are pathogenic and cause acute inflammations.


References in periodicals archive ?
Martirosian G, Bulanda M, Wojcik-Stojek B, et al: Acute appendicitis: the role of enterotoxigenic strains of Bacteroids fragilis and Clostridium difficile.
Nitrogen that is fixed by the bacteroids enters the plant's vascular system and can be transported throughout the plant.
In the legumerhizobia symbioses, the active host cells of the root nodule have a finite lifetime, and the intracellular bacteria within the nodule form bacteroids, which represents a terminal differentiation of these cells (Hirsch, 1992).
The uglycone was associated with the bacteroids (Meyer & Mellor, 1993).
In CSOM the wide range of microrganisms both aerobic (eg: Pseudomonas aeruginosa, Escherichia coli, streptococus pyogenes, proteous mirabils, klebsiela species) and anaerobic (eg: Bacteroids, Peptostreptococus, Propioni bacterium) and fungi (eg: Candida, Aspergilus, Penicilium and Rhizopus) are asocialted.
Streeter effects of salt stress on amino acid, organic acid, and carbohydrate composition of roots, bacteroids, and cytosol of alfalfa (Medicago sativa L.