However, GSH content was significantly higher for ABU 83972 than for the
UPEC in the stationary phase. No significant difference was observed in enzyme-synthesised GSH [γ-glutamylcysteine synthetase (GshA) and glutathione synthetase (GshB)] or GSSG content JPH203 cell line between UPEC and strain ABU 83972 or between growth phases (Additional file 1: Table S1 and Additional file 2: Table S2). Gor activity was significantly higher for strain ABU 83972 than that of UPEC for all measurements and varied significantly between mid-exponential phase and the stationary phase (Figure 3b, Additional file 1: Table S1 and Additional file 2: Table S2). Enzymes responsible for the detoxification of Selleck VRT752271 superoxide radicals and hydrogen peroxide Strain ABU 83972 growth in urine was associated with higher activity of the H2O2 detoxification system. Catalase activity
represents the peroxidase activity of several enzymes (Figure 1b), such as hydroperoxydase I (HPI), hydroperoxydase II (HPII) and the alkyl hydroperoxydase (AhpC) [39, 40]. Catalase activity of strain ABU 83972 was significantly higher in mid-exponential phase and stayed the same in stationary phase, for both groups (Figure 3d, Additional file 1: Table S1 and Additional file 2: Table S2). Enzymes responsible for superoxide radical O2 .- detoxification were induced more during growth and were also more active in this strain. All superoxide dismutases, periplasmic and cytosolic activity increased significantly during growth, becoming significantly greater in the stationary phase YH25448 manufacturer for strain ABU 83972 only (Figure 3e3f). Moreover, glucose-6 phosphate dehydrogenase (G6PDH) activity of strain ABU 83972 was significantly greater in the mid-exponential phase, and decreased to levels similar to those of UPEC in the stationary phase (Figure 3c). This more active G6PDH could contribute
to the synthesis of antioxydants (NADPH, GSH). As shown above, ABU 83972 growth in urine was related to a significantly higher level of TBARS in the mid-exponential phase. The high level of antioxidant defenses of strain ABU 83972 resulted in a decrease of TBARS, so there Tyrosine-protein kinase BLK was no difference in the levels of TBARS in the stationary phase between ABU strain 83972 and CFT073 or three UPEC. Discussion Our studies demonstrate that growth in urine may be associated with endogenous oxidative stress. It is well known that urine supports bacterial growth. Several studies have shown that UPEC strains grow well in human urine, whereas faecal isolates tended to grow more poorly [19, 41]. Other studies have also reported that ABU isolates grow faster than UPEC strains . However, Alteri and Mobley have recently shown that growth in urine is not restricted to UPEC bacteria or ABU strains. Commensal and enteropathogen E. coli strains produced growth curves indistinguishable from those of UPEC .