Bacteroids


Also found in: Dictionary, Thesaurus, Medical.
Related to Bacteroids: Bacteroides fragilis, Fusobacterium

Bacteroids

 

(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.

A. A. IMSHENETSKII

References in periodicals archive ?
The main aims of our work were comparative studies of the phase state and structure of the lipid bilayer of the outer membrane (OM) of the cells of four free-living rhizobium strains and also of the influence of the composition of symbiotic pairs on the state and structure of the outer membrane of bacteroids (bacteroid membrane, BM) and PBM, that forms the symbiosomes inside the plant cell.
For the fluorescence measuring, free-living bacteria, bacteroids, PL, and PBM vesicles were suspended in 0.7 M sucrose solution (pH 7.0).
Therefore, it was necessary to examine the changes in the lipid bilayer state of bacteria and bacteroids (microsymbiont), on the one hand, and of the PL of plant cell and PBM (macrosymbiont), on the other hand, to clarify the influence of symbiotic partners upon the state of the PBM's lipid bilayer, which determines the metabolite exchange between the symbionts and the membrane-bound proteins' activity.
Studies concerning nodule physiology and nodule functioning specified that the bacteria in bacteroids forms are surrounded in plant membranes resulting in the formation of symbiosomes [138].
Timony et al., "Analysis of the Rhizobium leguminosarum siderophore-uptake gene fliuA: differential expression in free-living bacteria and nitrogen-fixing bacteroids and distribution of an fhuA pseudogene in different strains," Microbiology, vol.
There are sequence of events that are necessary for symbiotic nitrogen fixation which includes preinfection, root colonization, root adhesion, hair branching, hair curling, infection, nodule initiation, bacterial release, bacteroid development, nodule function, nitrogen fixation, complementary functions, and nodule persistence [3].
Among the annerobes Peptostreptococcus was found in 5.69% cases followed by Bacteroides spp.
Aureus 18 12 6 36 (14.63%) E.Coli 10 4 8 22 (8.94%) Proteus mirabilis 17 6 3 26 (10.56%) Peptostreptococcus 5 4 5 14 (5.69%) Bacteroides spp.
Nitrogen fixation ([C.sub.2][H.sub.2] reduction) by broad bean (Vicia faba L.) nodules and bacteroids under water-restricted conditions.
For example, Prevotella and Lactobacillus were significantly correlated with each other (rho = 0.458) and with other bacteria such as Coprococcus (rho = 0.442, 0.261), Bacteroides (rho = 0.445, 0.312) and Streptococcus (rho = 0.218, 0.28).
Some gut bacteria of pigs, such as Clostridium, Bacillus, Ruminococcus, and Bacteroides, produce cellulases to help their host digest diet fibers.
A previous study found that the genera Prevotella and Bacteroides were more abundant in obese Gottingen minipigs, whereas Clostridium was higher in lean Gottingen minipigs.