DERMATOPHILUS CHELONAE SP-NOV, ISOLATED FROM CHELONIDS IN AUSTRALIA

Three isolates of a previously undescribed Demtatophilus sp, obtained from chelonids (two strains obtained from turtles and one strain obtai ned from a tortoise) were compared with 30 Dermatophilus congolensis i solates obtained from Australian mammals, The microscopic appearance, the colony morphology, and most biochemical test results for the chelo nid isolates were characteristic of the genus Dermatophilus. Our isola tes differed from the mammalian D, congolensis isolates in a number of cultural characteristics, including faster growth at 27 degrees C tha n at 37 degrees C, formation of two hemolysis zones around colonies on blood agar at 37 degrees C in the presence of 10% CO2, poor motility, and production of a distinctive odor, The DNA restriction enzyme dige stion and protein electrophoresis patterns of our strains were distinc t, The electrophoretic mobilities of 11 enzymes differed from the mobi lities observed with D, congolensis strains, A monoclonal antibody to a surface antigen of an ovine isolate did not react with zoospores or filaments of the chelonid isolates, Biochemical differences between ou r isolates and D, congolensis included the ability of the chelonid iso lates to reduce nitrate to nitrite and the fact that the chelonid isol ates exhibit collagenase activity in vitro, We propose that the chelon id isolates should be placed in a new species, Dermatophilus chelonae, Strain W16, which was isolated from a nose scab on a snapping turtle, is the type strain; a culture of this strain has been deposited in th e American Type Culture Collection as strain ATCC 51576.