Intraspecies diversity of Coxiella burnetii as revealed by com1 and mucZ sequence comparison

Coxiella burnetii Is classified within the gamma subgroup of the Proteobact eria. All strains tested to date have an identical 16S rRNA sequence but 20 different genotypes have been determined by pulsed field gel electrophores is (PFGE). In this study, intraspecies genetic diversity was investigated b y sequence comparison of 715 bp of the Com1 encoding gene (com1) and 774 bp of the MucZ encoding gene (mucZ) in 37 strains isolated from animals and h umans with acute or chronic Q fever in Europe, North America and Africa. Fi ve and four groups were established from sequence analysis of com1 and mucZ , respectively. Neither relation of the defined groups to geographical dist ribution of the isolates was noted nor relation to disease form (acute/chro nic). The same isolates were grouped together regardless of the gene being investigated. Comparison of the five proposed groups to previous groups, yi elded after digestion by NotI PFGE, allowed for an intermediate classificat ion of C. burnetii isolates between those obtained by using 16S rDNA (one g roup) and PFGE (20 groups). (C) 1999 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.