HELICOBACTER TROGONTUM SP-NOV, ISOLATED FROM THE RAT INTESTINE

A new Helicobacter species that colonizes the colonic mucosa of Wistar and Holtzman rats was isolated and characterized. This bacterium was gram negative, its cells were rod shaped with pointed ends, and its pr otoplasmic cylinder was entwined with periplasmic fibers. It was catal ase and oxidase positive, rapidly hydrolyzed urea, and was susceptible to metronidazole and resistant to cephalothin and nalidixic acid. The new organism was microaerophilic and grew at 42 degrees C, a feature that differentiates it from two other murine intestine colonizers, Hel icobacter hepaticus and Helicobacter muridarum. On the basis of 16S rR NA sequence analysis data, the new organism was identified as a Helico bacter species that is most closely related to N. hepaticus. This bact erium is named Helicobacter trogontum. The type strain is strain LRB 8 581 (= ATCC 700114).