A Study of Leptotrichia buccalis. I. Morphology and Preliminary Observations

¹ Department of Microbiology and the W. G. Zoller Memorial Dental Clinic, University of Chicago

A morphologic study of L. buccalis has been presented with a comparison with other studies by previous investigators. A method of maintaining these cultures either by lyophilization or by refrigerator storage was successfully achieved and has been presented.

There is a certain degree of pleomorphism exhibited by these cultures. However, in general, the morphology, with regard to both macroscopic or colonial and microscopic appearances, of this species appears to be quite stable. Further studies regarding their biochemical and other physiologic activities should be done to differentiate this species from other oral filamentous micro-organisms or filamentous micro-organisms from other sources.

The species L. buccalis appears to have a definite requirement for carbon dioxide and is incapable of reproduction at the same rate or magnitude in the absence of carbon dioxide either under anaerobic or microaerophilic conditions. Aerobic conditions require a lowering of Eh potential, as shown by the presence of good growth under these conditions when either cysteine or thioglycollate is added to the medium.

The classification and differentiation of this species has been briefly discussed, with the recommendation of retaining the genus and species name for this micro-organism.