Transposable Prophages in Leptospira: An Ancient, Now Diverse, Group Predominant in Causative Agents of Weil’s Disease

The virome associated with the corkscrew shaped bacterium Leptospira, responsible for Weil’s disease, is scarcely known, and genetic tools available for these bacteria remain limited. To reduce these two issues, potential transposable prophages were searched in Leptospiraceae genomes. The 236 predicted transposable prophages were particularly abundant in the most pathogenic leptospiral clade, being potentially involved in the acquisition of virulent traits. According to genomic similarities and phylogenies, these prophages are distantly related to known transposable phages and are organized into six groups, one of them encompassing prophages with unusual TA-TA ends. Interestingly, structural and transposition proteins reconstruct different relationships between groups, suggesting ancestral recombinations. Based on the baseplate phylogeny, two large clades emerge, with specific gene-contents and high sequence divergence reflecting their ancient origin. Despite their high divergence, the size and overall genomic organization of all prophages are very conserved, a testimony to the highly constrained nature of their genomes. Finally, similarities between these prophages and the three known non-transposable phages infecting L. biflexa, suggest gene transfer between different Caudovirales inside their leptospiral host, and the possibility to use some of the transposable prophages in that model strain.

A case report of Weil’s disease

This study present the details of a case of classical Weil’s Disease, which is a severe form of leptospirosis, presenting with symptoms of fever, jaundice, joint pain, haemorrhagic manifestations and renal failure. Leptospirosis is an uncommon but not rare health problem in a tropical country like India. Clinical manifestations along with the laboratory findings are elaborated, so that a differential diagnosis from other common ailments with similar manifestations can be considered in favour of the disease. An early empirical management on high clinical suspicion can help to avoid multi-organ dysfunction and mortality associated with this disease.

Draft Genome Sequences of Leptospira interrogans Serovar Copenhageni Strains Isolated from Patients with Weil’s Disease in Brazil

Leptospirosis is a worldwide zoonosis caused by pathogenic species of Leptospira. In Brazil, this disease is endemic, presenting epidemic potential in rainy seasons. Here, we announce the whole-genome sequences of two L. interrogans serovar Copenhageni strains isolated from blood samples from two icteric patients associated with severe leptospirosis in Brazil.