Arginine promotes Proteus mirabilis motility and fitness by contributing to conservation of the proton gradient and proton motive force

Abstract

Swarming contributes to Proteus mirabilis pathogenicity by facilitating access to the catheterized urinary tract. We previously demonstrated that 0.1–20 mmol/L arginine promotes swarming on normally nonpermissive media and that putrescine biosynthesis is required for arginine-induced swarming. We also previously determined that arginine-induced swarming is pH dependent, indicating that the external proton concentration is critical for arginine-dependent effects on swarming. In this study, we utilized survival at pH 5 and motility as surrogates for measuring changes in the proton gradient (ΔpH) and proton motive force (μH+) in response to arginine. We determined that arginine primarily contributes to ΔpH (and therefore μH+) through the action of arginine decarboxylase (speA), independent of the role of this enzyme in putrescine biosynthesis. In addition to being required for motility, speA also contributed to fitness during infection. In conclusion, consumption of intracellular protons via arginine decarboxylase is one mechanism used by P. mirabilis to conserve ΔpH and μH+ for motility.

Genes Required for the Anti-fungal Activity of a Bacterial Endophyte Isolated from a Corn Landrace Grown Continuously by Subsistence Farmers Since 1000 BC

“…Arginine can be converted to ornithine by arginase. In the context of the other mutants identified in this study, arginine was previously found to increase c-di-GMP levels and perhaps via this pathway, this amino acid was observed to promote biofilm formation ( Chen et al, 2013 ) and alter swarming ( Sturgill and Rather, 2004 ; Bernier et al, 2011 ; Armbruster et al, 2013 , 2014 ). Consistent with the literature, in this study, the ADC/ODC mutant caused reduced biofilm formation and loss of flagella, however, the swarming motility was not affected ( Figures 3A,O,Z ; Supplementary Table S3 ).…”

Pathogenesis of Proteus mirabilis Infection

“…As non-swarming mutants are only capable of migrating across hydrogel-coated catheters, swarming is likely an important aspect of initial bladder colonization in catheterized individuals. Five cues that can induce swarming in P. mirabilis are present in human urine (arginine, glutamine, histidine, malate, and ornithine), and may contribute to swarm cell differentiation and migration across urine-bathed catheters as they promote swarming on urine agar plates (165, 317, 318) (Fig. 33).…”

Deacidification by FhlA-dependent hydrogenase is involved in urease activity and urinary stone formation in uropathogenic Proteus mirabilis

“…that Hyf complex is similar to respiratory NADH dehydrogenase complex I 11,13,14 and the complex I was shown to provide the proton motive force (PMF) 31 , which could affect acid resistance, susceptibilities of polymyxin B and aminoglycosides, motility and growth under treatment of the PMF uncoupler [32][33][34][35][36][37] . We monitored the PMF- (Table 3; Fig.…”