Black-pigmented Bacteroides Species Research Articles

Bacteroides endodontalis sp. nov., an Asaccharolytic Black-Pigmented Bacteroides Species from Infected Dental Root Canals

A new species, Bacteroides endodontalis, is proposed for black-pigmented asaccharolytic Bacteroides strains that have negligible deoxyribonucleic acid homology with either Bacteroides gingivalis or Bacteroides asaccharolyticus. Strain HG370 (= ATCC 35406) is the type strain. Unlike B. gingivalis, B. endodontalis does not agglutinate sheep erythrocytes or produce phenylacetic acid. B. endodontalis resembles B. asaccharolyticus physiologically but can be distinguished by its lower deoxyribonucleic acid guanine-plus-cytosine content (50 versus 53 to 54 mol%), by its serological reactions, by its electrophoretic patterns of proteins, and possibly by its menadione requirement.

Black-pigmented Bacteroides species, Capnocytophaga species, and Actinobacillus actinomycetemcomitans in human periodontal disease: virulence factors in colonization, survival, and tissue destruction.

Black-pigmented Bacteroides species, Capnocytophaga species, and Actinobacillus actinomycetemcomitans in human periodontal disease: virulence factors in colonization, survival, and tissue destruction.

Degradation of the human proteinase inhibitors alpha-1-antitrypsin and alpha-2-macroglobulin by Bacteroides gingivalis.

Various strains of black-pigmented Bacteroides species were grown on horse blood agar and suspended in human serum. After various times of incubation the effect of the bacteria on the serum was evaluated by polyacrylamide gel electrophoresis and "rocket" immunoelectrophoresis. The formation of trichloroacetic acid-soluble material in the suspensions and the capacity of the treated sera to inhibit the activity of trypsin were also determined. The two tested strains of Bacteroides gingivalis (W83, H185) degraded most serum proteins, including the plasma proteinase inhibitors alpha-1-antitrypsin and alpha-2-macroglobulin. They did not, however, degrade alpha-1-antichymotrypsin. Bacteroides intermedius NCTC 9336, Bacteroides asaccharolyticus NCTC 9337, and an asaccharolytic oral strain different from B. gingivalis (BN11a-f) did not degrade the plasma proteinase inhibitors. These strains were, however, able to inactivate the capacity of serum to inhibit the activity of trypsin.

Proteolytic activities of gram-negative bacteria isolated from human periodontal lesions.

Enzymatic activity of gram-negative bacteria isolated from human periodontal lesions were examined in this study. The cells of Bacteroides gingivalis showed caseinolytic, trypsin-like, collagenase and immunoglobulin-degradating activities. The caseinolytic activity of black-pigmented Bacteroides species was found both in the culture supernatant and membraneous component of cells. No strains tested possessed strong mucopolysaccharidase activity. Capnocytophaga strains showed lipase (C14) and trypsin-like activities. No other strains of Bacteroides, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum or Eikenella corrodens exhibited any proteolytic activity.

Bacterial antibody titers in ligature-induced periodontitis in beagle dogs.

Serum antibodies to indigenous bacteria in ten beagle dogs were examined over a 7-month period during the development of ligature-induced periodontitis. Gram-negative strains comprised approximately 75% of the cultivable periodontitis microflora with a predominance of black-pigmented Bacteroides species. A total of 44 bacterial strains representing the predominant cultivable subgingival beagle dog microflora was selected for antibody determination. The IgG and, in some cases, IgM serum antibody titers to these organisms were determined by indirect immunofluorescence. The antibody titers to most test strains remained unchanged during the experimental period. Gram-negative bacteria generally exhibited lower titers than the Gram-positive bacteria. Especially low titers were found for the black-pigmented Bacteroides. Four dogs that developed the most severe periodontitis showed about 2-fold higher IgG titers to some Gram-negative anaerobic rods in the pre-ligation period than dogs that developed a more moderate periodontitis. These data suggested a possible diagnostic value of such antibody determinations. However, the overall finding of the present study was that serum antibody titers to key periodontopathic organisms remained low throughout the experiment. This result may suggest that the rapid periodontal destruction in ligature-induced periodontitis is due in part to an inadequate antibody response against the infecting microorganisms and their pathogenic products.

Effect of culture filtrates of black-pigmented Bacteroides species on the matrix production of chick embryo chondrocytes in vitro

Effect of culture filtrates of black-pigmented Bacteroides species on the matrix production of chick embryo chondrocytes in vitro

Bacteroides gingivalis, Bacteroides asaccharolyticus, andBacteroides melaninogenicus subspecies: Cell surface morphology and adherence to erythrocytes and human buccal epithelial cells

All study strains ofBacteroides gingivalis, B. asaccharolyticus, andB. melaninogenicus subspecies possessed numerous pilus-like fibers and capsule-like outer surface structures. The capsular morphology varied between the different species and subspecies.B. gingivalis strongly agglutinated 16 erythrocyte species studied.B. asaccharolyticus showed variable and weak agglutination of only a few erythrocyte species.B. melaninogenicus subsp.intermedius strains strongly agglutinated rabbit erythrocytes and exhibited variable, often weak agglutination of 8 other erythrocyte species. Preparations of capsular polysaccharide or lipopolysaccharide fromB. gingivalis failed to agglutinate human erythrocytes, while pili preparations from the same organisms possessed marked hemagglutinating activity.B. gingivalis cells adhered in high numbers to human buccal epithelial cells, whereas strains ofB. asaccharolyticus failed to show measurable adherence. Oral strains ofB. melaninogenicus subsp.intermedius feebly adhered to the buccal epithelial cells. Pretreatment ofB. gingivalis cells with serum or saliva prevented the adherence to epithelial cells. Our findings suggest that cell surfaces with distinct properties exist on the various black-pigmentedBacteroides species and subspecies and this may accout for markedly differing ability of these organisms to attach to mammalian cells.