LAUSR

Cholera caused by the Gram negative bacterium Vibrio cholerae has been a serious threat in under developed countries. Though rehydration therapy has been the mainstay of the disease management, antibiotics are also being used as an adjunct in the treatment regime causing an increase in the circulation of antibiotic resistant V. cholerae strains. In the present study, adaptive laboratory evolution, whole genome sequencing and molecular docking studies were carried out to identify putative mutations related to doxycycline resistance in V. cholerae. rpsJ (V57L) was identified to be important in conferring doxycycline resistance as the mutationwas identified to alter the ribosome structure near the doxycycline binding site as revealed by the molecular docking studies. Dxycycline stress also induced co-resistance to colistin antibiotic, a last resort drug to treat extensively drug resistant bacteria. The study illustrates a possible mechanism of doxycycline selected resistance in V. cholerae for the first time and doxycycline selected co-resistance which warrants strict restrictions on the indiscriminate use of antibiotics.