The first definitive evidence for a phosphenolpyruvate-dependent sugar phosphotransferase sugar transport system in the family Bacteroidaceae was shown in our studies of sucrose utilization by Fusobacterium mortiferum ATCC 25557. Growth of F. mortiferum on sucrose resulted in cells which fermented sucrose to principally acetic and butyric acids and whose phosphorylation of sucrose was dependent on phosphoenolpyruvate. Anaerobic conditions were necessary for sucrose use by F. mortiferum. Two enzymes necessary for sucrose use, a sucrose- 6-phosphate hydrolase and an ATP dependent fructokinase, were purified to electrophoretic homogeneity from extracts of sucrose grown F. mortiferum. The physicochemical and catalytic properties of these enzymes have been examined, and the N-terminal amino acid sequences of both proteins determined. Disaccharide hydrolases have been demonstrated in sonic extracts of F. mortiferum grown on disaccharides and raffinose. A sucrose hydrolase has been demonstrated in extracts of melibiose grown F. mortiferum which is very similar to the sucrose-6-phosphate hydrolase obtained from sucrose grown cells. Similar hydrolases and alpha galactosidases have been shown in melibiose and raffinose grown cells of F. mortiferum suggesting that these are parts of a raffinose operon in this organism. A cystathionase has been demonstrated in extracts of F. mortiferum which is cross reactive with antibody to a homogeneously purified cystathionase from Bordetella avium having toxicity to osteoblasts in tissue culture. Similar activities have been shown in cultures of a variety of other fusobacteria.
