Summary: Osmoregulatory transporters ProP and ProU mediate the use of betaines as osmoprotectants by Glycine betaine and proline betaine are present in mammalian urines. Betaine uptake may therefore facilitate the growth of in the urinary tract, an environment of fluctuating osmolality. ProP transporter activity was approximately threefold higher in a pyelonephritis isolate, HU734, than in K-12. The growth rate of HU734 in aerated minimal salts medium was reduced twofold by 0.2 M NaCl in the absence and by 0.55 M NaCI in the presence of glycine betaine. Maximal growth rate stimulation was achieved when glycine betaine was added at a concentration as low as 25 μM. Deletion of the locus impaired the growth rate of HU734 in human urine but not in minimal medium supplemented with NaCI (0.4 M), with or without glycine betaine (0.1 mM). The expression of pyelonephritis-associated (P) pili was reduced when HU734 was cultured in a rich culture medium (LB) of elevated salinity. The lesion had no influence on P pilus expression or on the recovery of bacteria from the kidneys of inoculated mice. However, it did reduce their recovery from the bladders of inoculated mice 100-fold. These data provide the first direct evidence that osmoprotective betaine accumulation and transporter ProP are pertinent to both growth in human urine and colonization of the murine urinary tract by uropathogenic


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error