Characterization of Bacteroides asaccharolyticus and B. melaninogenicus oral isolates

Abstract

Experiments were designed to characterize a number of oral "pigmented" Bacteroides isolates with regard to their pathogenicity in an experimental model system and a number of other properties. T these include fatty acid determination, hemagglutination studies, collagenase and protease activities, and vitamin K dependency. Oral B, asaccharolyticus and B, melaninogenicus isolates differed from one another in phenylacetic acid production, hemagglutination, collagenase activity, and pathogenicity. All B. asaccharolyticus were found to be pathogenic in the vivo mixed infection model and this property could be correlated with biochemical enzymatic activities.

Degradation of Human Immunoglobulins G and M and Complement Factors C3 and C5 by Black-Pigmented Bacteroides

“…Also, in experimental polymicrobial infections in guinea pigs, the addition of strains of black-pigmented Bacteroides to an avirulent mixture of bacteria can promote the survival of those bacteria despite the presence of large numbers polymorphonuclear leukocytes (MacDonald, Socransky and Gibbons, 1963;Socransky and Gibbons, 1965;Sundqvist et al, 1979;Mayrand et al, 1980). It is not known how the bacteria evade the antimicrobial action of the leukocytes.…”

“…B. gingivalis enzymes degrade not only C3, C5 and immunoglobulins of human serum but also albumin, haptoglobulin, haemopexin, transferrin and the proteinase inhibitors a-1 -antitrypsin and a-2-macroglobulin . These characteristics may explain the high pathogenic potential of B. gingivalis (McDonald et al, 1963;Mayrand et al, 1980;van Steenbergen et al, 1982;Sundqvist et al, 1984). By degrading complement and immunoglobulin, B. gingivalis may evade the phagocytic host defence.…”

Cytotoxic Activity of Bacteroides Gingivalis and Bacteroides Asaccharolyticus

“…Recent evidence suggests that B. gingivalis is more virulent than B. melaninogenicus and B. asuccharolyticus (Mayrand et al, 1980;van Steenbergen et al, in press). The role of the cytotoxin in disease remains to be elucidated.…”

Saliva-Bacterium Interactions in Oral Microbial Ecology

“…Many oral bacteria, especially anaerobes, secrete a variety of proteases (Mayrand et al, 1980) that can act on numerous host proteins, including collagen (Robertson et al, 1984), complement (Schenkein, 1988), fibronectin (Pellat et al, 1989;Wikstrom and Linde, 1986;Lantz et al, 199 la), and fibrinogen (Lantz et al,199 ib). Little work has focused, however, on the degradation of salivary molecules by oral bacteria.…”