ABSTRACT
The pronounced change in the buoyant density of Coxiella burnetii in CsCl gradients that was caused by treatment with formalin or ultraviolet radiation was not observed with Rickettsia rickettsii.
Subject(s)
Coxiella , Rickettsia rickettsii , Centrifugation, Density Gradient , Coxiella/drug effects , Coxiella/radiation effects , Formaldehyde/pharmacology , Rickettsia rickettsii/drug effects , Rickettsia rickettsii/radiation effects , Ultraviolet RaysABSTRACT
The metabolism of Rickettsia tsutsugamushi (Gilliam strain) multiplying in irradiated L cells was investigated by methods involving the use of (14)C-labeled substrates and cycloheximide, an inhibitor of eukaryotic metabolism. Cycloheximide-resistant amino acid and adenine incorporations were appreciably higher in infected than in uninfected cultures during the period from 3 to 5 or 6 days postinoculation. The metabolism of R. rickettsi was similarly studied in primary duck embryo cells, which are more susceptible to infection with this rickettsia than are L cells. A difference in cycloheximide-resistant activity between infected and uninfected cultures was also noted, but was small. This finding is attributed to the more limited growth of R. rickettsi.
