title: Analysis of the HD-GYP domain cyclic dimeric GMP phosphodiesterase reveals a role in motility and the enzootic life cycle of Borrelia burgdorferi.
abstract: HD-GYP domain cyclic dimeric GMP (c-di-GMP) phosphodiesterases are implicated in motility and virulence in bacteria. Borrelia burgdorferi possesses a single set of c-di-GMP-metabolizing enzymes, including a putative HD-GYP domain protein, BB0374. Recently, we characterized the EAL domain phosphodiesterase PdeA. A mutation in pdeA resulted in cells that were defective in motility and virulence. Here we demonstrate that BB0374/PdeB specifically hydrolyzed c-di-GMP with a K(m) of 2.9 nM, confirming that it is a functional phosphodiesterase. Furthermore, by measuring phosphodiesterase enzyme activity in extracts from cells containing the pdeA pdeB double mutant, we demonstrate that no additional phosphodiesterases are present in B. burgdorferi. pdeB single mutant cells exhibit significantly increased flexing, indicating a role for c-di-GMP in motility. Constructing and analyzing a pilZ pdeB double mutant suggests that PilZ likely interacts with chemotaxis signaling. While virulence in needle-inoculated C3H/HeN mice did not appear to be altered significantly in pdeB mutant cells, these cells exhibited a reduced ability to survive in Ixodes scapularis ticks. Consequently, those ticks were unable to transmit the infection to naïve mice. All of these phenotypes were restored when the mutant was complemented. Identification of this role of pdeB increases our understanding of the c-di-GMP signaling network in motility regulation and the life cycle of B. burgdorferi.
authors.affiliation: Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA.
authors.forename: Syed Z
authors.initials: SZ
authors.lastname: Sultan
authors.forename: Joshua E
authors.initials: JE
authors.lastname: Pitzer
authors.forename: Tristan
authors.initials: T
authors.lastname: Boquoi
authors.forename: Gerry
authors.initials: G
authors.lastname: Hobbs
authors.forename: Michael R
authors.initials: MR
authors.lastname: Miller
authors.forename: M A
authors.initials: MA
authors.lastname: Motaleb
mesh_terms: D015106:3',5'-Cyclic-GMP Phosphodiesterases / Q000378:metabolism*; D000818:Animals; D025065:Borrelia burgdorferi / Q000378:metabolism / Q000472:pathogenicity / Q000502:physiology*; D006152:Cyclic GMP / Q000031:analogs & derivatives / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D017353:Gene Deletion; D005816:Genetic Complementation Test; D018884:Ixodes / Q000382:microbiology*; D007700:Kinetics; D008124:Locomotion; D008193:Lyme Disease / Q000382:microbiology / Q000473:pathology; D051379:Mice; D008809:Mice, Inbred C3H; D012376:Rodent Diseases / Q000382:microbiology / Q000473:pathology; D014774:Virulence
chemical_list: C062025:bis(3',5')-cyclic diguanylic acid; D015106:3',5'-Cyclic-GMP Phosphodiesterases; D006152:Cyclic GMP