Tropheryma whipplei is an emerging huamn pathogen which causes Whipple's disease, which is characterized by systemic effects with alteration in the general state of health, chronic enteritis, joint pain, culture-negative endocarditis, encephalitis and uveitis. The reservoir and mode of transmission of this bacterium are unknown, and treatment of the disease is poorly codified.

We have isolated the first strain of Tropheryma whipplei (the Twist strain) and shown that it is an intracellular bacterium. Analysis of 16S rDNA, groEL and rpoB sequences place it between the peptidoglycan group B actinomycetes and the Cellulomonadaceae.

Sequencing of the genome of this first strain will lead to a better understanding of the evolutionary and physiologic bases for the obligatory intracellular parasitism of this bacteria.