Effect of increasing concentrations of P5C reductase inhibitors on S. pyogenes growth. Late-log grown cultures were used to inoculate parallel tubes containing 3 ml of minimal medium to an initial OD600 of 0.1. One hour after the inoculum, a proper amount of a given bisphosphonate was added. The growth was followed for the subsequent 12 h as the increase in absorbance (a, d). After logarithmic transformation of the data, growth constants were calculated over the rectilinear part of the curves, whereas the final biomass (fresh weight) was evaluated following centrifugation 24 h after the inoculum (b, c)