Spirochetes are a large and diverse group of helical or corkscrew-like bacteria that are adapted to live in a variety of environments, having several pathogenic genera, including the bacteria responsible for syphilis and Lyme disease. Leptospira interrogans causes leptospirosis in humans, a disease characterized by sudden hemorrhage resulting in severe or fatal damage to the liver, kidney, and lungs. Genetic analysis of the spirochetes has been hampered by the complexity of growth requirements and relatively long generation times. In the April 24 Nature, Shuang-Xi Ren and colleagues at the Chinese Academy of Sciences, Beijing, China, enable a thorough understanding of the mechanisms of virulence and pathology in L. interrogans (Nature, 422:888-893, April 24, 2003).
Ren et al. used whole-genome sequencing to analyze the virulent serovar type strain (Lai) of L. interrogans and predicted and compared protein-coding sequences within and outside the spirochete phylum. They identified a 4.33 Mb large chromosome ...