Abstract
A marked reduction in uptake of α-santonin, accompanied by loss of ability of cells to transform the substrate, is observed on shocking Sphingomonas paucimobilis strain S ATCC 43388 cells by freeze - thaw method. The shock fluid shows a 26% quench in fluorescence at 350nm on incubation with the substrate. Addition of shock fluid to the freeze thawed cells restores both uptake as well as transformation of α-santonin to near normal.