This AREA project aims to determine the function of surface adhesins in Veillonella's role as keystone species in periodontal dysbiosis. Periodontal diseases especially periodontitis affect the majority of people 65 years and older, and is the major cause of tooth loss in this population. Development of periodontitis involves a serial transition from healthy gum to gingivitis to periodontitis. It has been well established that periodontitis results from dysbiotic interactions between the subgingival microbiota and the host. In the center of this dysbiotic transition are Fusobacterium sp, especially F. nucleatum (Fn) and Veillonella sp (Va). Fn is a middle colonizer and ubiquitously present in all human dental biofilms. However, in healthy subjects, Fn exists in low abundance, while in subjects with gingivitis, its numbers increase substantially leading to gingival inflammation, which then causes increased exudates in the gingival pocket, enhancing growth of proteolytic, tissue destructive periodontopathogens. Fn also recruits many periodontopathogens to the biofilm via cell-cell coaggregation. While Fn is ubiquitously present in healthy biofilm, it cannot grow in vitro under conditions mimicking oral health, unless Va is present. Va is considered an early colonizer and ubiquitously present and highly abundant in oral biofilms. Va also coaggregates with Fn. These findings led us to hypothesize that it is the Va bacteria in the early biofilm that enable the growh of Fn, and by doing so function as keystone species in the subsequent dysbiotic transition of the oral biofilm.
Two specific Aims are proposed to test this hypothesis.
Aim 1 is to identify the functional domains of a streptococcal specific and an Fn specific adhesion, Aim2 is to determine the function of these adhesins on Fn growth in a 3- species biofilm model. We anticipate that by understanding the mechanisms of coaggregation and its effect on the growth of Fn, we could gain insights into the dysbiotic transformation of the dental biofilm by Veillonella. Currently, almost nothing is known about the earliest events leading to dysbiosis in the oral biofilm. Our study will have significant impact on development of strategies for periodontal disease prevention.
Periodontal diseases especially periodontitis affect the majority of people 65 years and older, and is the major cause of tooth loss in this population. Periodontitis is caused by a dysfunctional dental biofilm, thus understanding the mechanisms of this pathogenic transformation will help devise novel strategies for disease prevention.
|Zhou, Peng; Li, Xiaoli; Huang, I-Hsiu et al. (2017) Veillonella Catalase Protects the Growth of Fusobacterium nucleatum in Microaerophilic and Streptococcus gordonii-Resident Environments. Appl Environ Microbiol 83:|
|Zhou, Peng; Xie, Gary; Li, Xiaoli et al. (2017) Complete Genome Sequence of Veillonella atypica OK5, the First Transformable Strain in the Species. Genome Announc 5:|
|Zhou, Peng; Li, Xiaoli; Qi, Fengxia (2016) Identification and characterization of a haem biosynthesis locus in Veillonella. Microbiology 162:1735-1743|
|Zhou, Peng; Liu, Jinman; Li, Xiaoli et al. (2015) The Sialic Acid Binding Protein, Hsa, in Streptococcus gordonii DL1 also Mediates Intergeneric Coaggregation with Veillonella Species. PLoS One 10:e0143898|
|Zhou, Peng; Li, Xiaoli; Qi, Fengxia (2015) Establishment of a counter-selectable markerless mutagenesis system in Veillonella atypica. J Microbiol Methods 112:70-2|
|Chen, Xi; Liu, Nan; Khajotia, Sharukh et al. (2015) RNases J1 and J2 are critical pleiotropic regulators in Streptococcus mutans. Microbiology 161:797-806|
|Zhou, Peng; Liu, Jinman; Merritt, Justin et al. (2015) A YadA-like autotransporter, Hag1 in Veillonella atypica is a multivalent hemagglutinin involved in adherence to oral streptococci, Porphyromonas gingivalis, and human oral buccal cells. Mol Oral Microbiol 30:269-279|
|Liu, Jinman; Xie, Zhoujie; Merritt, Justin et al. (2012) Establishment of a tractable genetic transformation system in Veillonella spp. Appl Environ Microbiol 78:3488-91|
|Liu, Jinman; Merritt, Justin; Qi, Fengxia (2011) Genetic transformation of Veillonella parvula. FEMS Microbiol Lett 322:138-44|
|Liu, Jinman; Wu, Chenggang; Huang, I-Hsiu et al. (2011) Differential response of Streptococcus mutans towards friend and foe in mixed-species cultures. Microbiology 157:2433-44|