RT-PCR analysis of vanT expression in wild -type (M93Sm and NB10) and vanT mutant (M02 and NB02) strains of V. anguillarum . Cells were grown overnight in LB20, washed twice in NSS, and resuspended in either LB20 or NSSM at 2 × 109 CFU/ml. RNA from LB20- (L) and NSSM- (M) grown cells was prepared and used in RT-PCR reactions. RNA was extracted from cells at 0 h and 3 h after resuspension. As a positive control, PCR was performed on DNA from M93Sm (lane A) and NB10 (lane B). As a negative control, RT was omitted from the reaction containing RNA samples; a representative result is shown in lane C. The PCR and RT-PCR products were visualized on a 1% agarose TAE gel containing ethidium bromide. Molecular weight standard (indicated in kilobase pairs) are in lane S. The data presented are representative of three replicate experiments.