title: Differential control of Yersinia pestis biofilm formation in vitro and in the flea vector by two c-di-GMP diguanylate cyclases.
abstract: Yersinia pestis forms a biofilm in the foregut of its flea vector that promotes transmission by flea bite. As in many bacteria, biofilm formation in Y. pestis is controlled by intracellular levels of the bacterial second messenger c-di-GMP. Two Y. pestis diguanylate cyclase (DGC) enzymes, encoded by hmsT and y3730, and one phosphodiesterase (PDE), encoded by hmsP, have been shown to control biofilm production in vitro via their opposing c-di-GMP synthesis and degradation activities, respectively. In this study, we provide further evidence that hmsT, hmsP, and y3730 are the only three genes involved in c-di-GMP metabolism in Y. pestis and evaluated the two DGCs for their comparative roles in biofilm formation in vitro and in the flea vector. As with HmsT, the DGC activity of Y3730 depended on a catalytic GGDEF domain, but the relative contribution of the two enzymes to the biofilm phenotype was influenced strongly by the environmental niche. Deletion of y3730 had a very minor effect on in vitro biofilm formation, but resulted in greatly reduced biofilm formation in the flea. In contrast, the predominant effect of hmsT was on in vitro biofilm formation. DGC activity was also required for the Hms-independent autoaggregation phenotype of Y. pestis, but was not required for virulence in a mouse model of bubonic plague. Our results confirm that only one PDE (HmsP) and two DGCs (HmsT and Y3730) control c-di-GMP levels in Y. pestis, indicate that hmsT and y3730 are regulated post-transcriptionally to differentially control biofilm formation in vitro and in the flea vector, and identify a second c-di-GMP-regulated phenotype in Y. pestis.
authors.affiliation: Laboratory of Zoonotic Pathogens, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America. sunyc@ipbcams.ac.cn
authors.forename: Yi-Cheng
authors.initials: YC
authors.lastname: Sun
authors.forename: Alexandra
authors.initials: A
authors.lastname: Koumoutsi
authors.forename: Clayton
authors.initials: C
authors.lastname: Jarrett
authors.forename: Kevin
authors.initials: K
authors.lastname: Lawrence
authors.forename: Frank C
authors.initials: FC
authors.lastname: Gherardini
authors.forename: Creg
authors.initials: C
authors.lastname: Darby
authors.forename: B Joseph
authors.initials: BJ
authors.lastname: Hinnebusch
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism*; D018441:Biofilms; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000737:chemistry; D004195:Disease Models, Animal; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000378:metabolism*; D051379:Mice; D009154:Mutation; D010641:Phenotype; D019761:Phosphorus-Oxygen Lyases / Q000737:chemistry* / Q000378:metabolism*; D010930:Plague / Q000378:metabolism; D017434:Protein Structure, Tertiary; D005423:Siphonaptera; D014774:Virulence / Q000235:genetics; D015010:Yersinia pestis / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; C122178:HMST protein, Yersinia pestis; C062025:bis(3',5')-cyclic diguanylic acid; D019761:Phosphorus-Oxygen Lyases; C060720:diguanylate cyclase; D006152:Cyclic GMP