HYDROLYTIC ENZYMES AND LECTIN-BINDING ACTIVITY OF BLACK-PIGMENTED ANAEROBIC RODS

Recent taxonomic studies on black-pigmented anaerobic rods, a group of bacteria found on mucosal surfaces of humans and animals, led to the subdivision of existing species and to the creation of new species. Th e aim of this study was to characterize all 11 currently recognized sp ecies of black-pigmented bacteria (55 strains) for their ability to hy drolyse a variety of natural and synthetic substrates and for their le ctin reactivity. Although most of the strains demonstrated some activi ty against proteinaceous substrates, Porphyromonas gingivalis was the only species able to hydrolyse type I collagen. Most strains possessed glycylprolyl protease activity, elastase-like activity and phospholip ase C activity, whereas trypsin-like activity was restricted to P. gin givalis, Porphyromonas salivosa and Bacteroides macacae. beta-Lactamas e activity was demonstrated in five strains belonging to the saccharol ytic group. The lectin reactivity of the bacteria was determined by a dot-blot procedure using horseradish-peroxidase-conjugated lectins. Th ree lectins, LOTUS A, RCA-I and ConA, failed to react with any of the bacteria tested. WGA reacted strongly with the cell surface of human b iotypes of asaccharolytic black-pigmented bacteria (P. gingivalis, Por phyromonas asaccharolytica and Porphyromonas endodontalis) and Prevote lla intermedia. The animal biotype strains of P. gingivalis showed a h igher affinity for SBA and PNA than for WGA.