Morphological And Physiological Responses To Npcrna Pmir-137 Knockout In Proteus Mirabilis

Abstract

Proteus mirabilis is a Gram-negative, facultatively anaerobic rod-shaped bacterium, known for its ability to form multicellular surface mobility termed swarming. Proteus mirabilis causes symptomatic urinary tract infections, such as cystitis and pyelonephritis, and catheter-associated urinary tract infections. There are several virulent factors associated with P. mirabilis such as flagella, fimbriae, hemolysin, urease, and outer membrane proteins. It uses flagella-mediated motility in order to reach the ureters and renal parenchyma in the host urinary system, eventually causing urinary tract infection. Flagella are hollow tubes composed of a long helical filament, a small, curved structure (the hook) and the basal body embedded on the cell surface which plays a significant role in bacterial movement through aqueous environment. Our previous study revealed 240 novel Hfq-associated nonprotein coding RNAs in P. mirabilis. Interestingly, npcRNA PmiR-137, the Hfq-associated novel non-protein coding RNA is predicted to regulate the virulence associated with the mRNA of flagella proteins. Thus, the PmiR-137 was knocked out to study the morphological and physiological differences between the wild-type and mutant strain. The mutant strain exhibited higher motility and biofilm production compared to the wild-type strain. The mutant strain was unable to survive heat shock and oxidative stress conditions, resulting in a lower percentage of relative survival rate. However, no morphological differences could be observed between the wild-type and mutant strain.