, the cause of louse-borne relapsing fever, has until recently been considered noncultivable, which has prevented characterization of this spirochete. We successfully cultivated 18 strains from patients with louse-borne relapsing fever and present the initial characterization of these isolates. Electron microscopy revealed spirochetal cells with pointed ends, an average wavelength of 1.8 μ.m, an amplitude of 0.8 μm, and 8 to 10 periplasmic flagella. The G+C ratio was 28.4 mol%. Whole DNA-DNA hybridizations showed similarity between the isolates of but not with , or the Lyme-associated borreliae. Sequencing studies of both the flagellin and 16S RNA genes revealed that the greatest similarity was between and Analysis of the sodium dodecyl sulfate-polyacrylamide gel electrophoresis profiles of strains revealed four groups based on the position of a major protein band (one of the groups showed some heterogeneity and was subdivided into four subgroups). Pulsed-field gel electrophoresis revealed five distinct patterns.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error