Extended spectrum multi-drug resistance versus pathogenic factors- swarming, proteases, and urease- of Proteus species

Abstract

Multi-drug resistance (MDR) in isolates of P. vulgaris (Pv ), P. mirabilis (Pm ), P. hauseri (Ph ) and P. penneri (Pp ) was determined in our previous study. Here pathogenic features of isolates were investigated. Strong swarming motility was found in isolate 91 2(Pm ) although MDR had no effect on swarming. Inter-species swarming patterns in Proteus were different regardless of MDR-spectrum. Pv , Pm showed bull's eye swarming pattern and Pp , Ph featureless mat. Isolates’ variable onset times for urea hydrolysis were a consequence of urease producing abilities but not the activities of ureases. Possibly urease production is correlated to the cellular response under urea-induced media. In contrast, total time required to consume a constant amount of urea was identical to intra-species Proteus isolates. Ph requires 3h, Pm 5h, Pp 6-7h and Pv 9h that can be used as research tool for identification of Proteus species. MDR had no effects on the rate of cell proliferation. Ph is found as more opportunistic pathogen than others. Strong proteolysis by proteases of isolate 91 2 (Pm ) was a hyperactive effect of ZapA or other unknown proteases. Thus, 91 2 (Pm ) marked as most pathogenic Proteus strain regarding swarming and proteases. Further qualitative and quantitative analyses of proteases in 91 2 (Pm ) remain to be elucidated.