CULTURE AND CHARACTERISTICS OF HELICOBACTER-BIZZOZERONII, A NEW CANINE GASTRIC HELICOBACTER SP

Organisms whose cells were large, tight spirals were isolated from gas tric biopsies of dogs. Touch cytology samples from all of the dogs con tained large spiral organisms. Characteristics of 10 strains are descr ibed. These organisms were 5 to 10 mu m long by 0.3 mu m wide, and eac h cell had 10 to 20 sheathed flagella at both ends of the cell. The ce lls did not have periplasmic fibrils. These organisms were microaeroph ilic and grew at 37 and 42 degrees C but not at 25 degrees C on brain heart infusion agar containing blood. They did not grow on brucella bl ood agar, They were catalase and oxidase positive, hydrolyzed urea but not hippurate, reduced nitrate, and were resistant to nalidixic acid but susceptible to cephalothin and metronidazole. In contrast to Helic obacter felis, they hydrolyzed indoxyl acetate, The sodium dodecyl sul fate-polyacrylamide gel electrophoresis protein profiles of all of the strains were similar, and the protein patterns of these organisms dif fered from those of other Helicobacter spp, Dot blot DNA-DNA hybridiza tion experiments revealed that the new strains were closely related to each other but clearly different from H. felis, Helicobacter pylori, Helicobacter mustelae, and Campylobacter jejuni., The name Helicobacte r bizzozeronii sp, nov, is proposed for these organisms, Our results s uggest that other ''uncultured'' gastric helicobacters may be cultured if optimal culture conditions are found.