Biological characterization of a c-di-GMP metabolism-related gene PA2072 mutant from Pseudomonas aeruginosa PAO1

Abstract:

Abstract:[Background] Pseudomonas aeruginosa, a Gram-negative bacterium, is a common opportunistic pathogen of nosocomial infection. Cyclic di-guanosine monophosphate (c-di-GMP), a secondary messenger ubiquitous in bacteria, plays a role in regulating the physiological and biochemical functions of bacteria. PA2072 is a gene involved in c-di-GMP metabolism in P. aeruginosa PAO1. [Objective] To investigate the biological functions of PA2072 in P. aeruginosa PAO1. [Methods] The suicide vectors carrying the full length and different domains of PA2072 were constructed by common molecular cloning technology. Three mutant strains of PA2072 were obtained and studied. The swimming, swarming, and twitching motility, as well as the biofilm formation, of the strains was studied. Congo Red staining was further employed to determine the c-di-GMP levels of the strains. [Results] PA2072 mutant strains and complement strains were successfully constructed. The deletion of PA2072 affected the biofilm formation, and the individual domains of PA2072 also played a role in biofilm formation. The motility tests showed that PA2072 was involved in the regulation of bacterial motility. Compared with the wild-type PAO1 strain, PA2072-delected strains displayed red lawn, which indicated an increased level of intracellular c-di-GMP. [Conclusion] The deletion of PA2072 affects the phenotypes of P. aeruginosa, which might be because of the changes in c-di-GMP level. Our work lays a foundation for further characterization of the biological functions of PA2072.

Key words:Pseudomonas aeruginosa PAO1;c-di-GMP;PA2072-deleted mutant