New advances to break the genetic tractability barrier of human Prevotella species

The Prevotella genus is one of the most abundant and diverse genera in the oral cavity, and includes numerous prominent oral microbiome species that have been recognized for decades to play critical roles in mucosal health and disease. Accordingly, recent culture-independent studies have found oral Prevotella species to be strongly associated with a broad range of both oral and extraoral conditions, especially polymicrobial abscesses and multiple types of malignancies. Despite this, shockingly little is known about the biology of all Prevotella species, largely as a consequence of the notorious genetic intractability within the entire genus. Recently, we encountered this same limitation due to our ongoing studies of host interactions with our Prevotella human odontogenic abscess clinical isolates. While we have identified a variety of intriguing host interaction phenotypes, further mechanistic studies of these phenomena have been stymied by the lack of options for Prevotella genetic manipulation. Consequently, we have recently focused our attention on genetic system development for oral prevotellae. In our preliminary studies, we provide evidence of natural competence from 20 fully sequenced abscess clinical isolates of P. melaninogenica, and we have been able to exploit this ability to genetically manipulate multiple strains using cloning-independent methodologies. Furthermore, preliminary evidence suggests that the P. melaninogenica DNA uptake apparatus is likely to represent an entirely new class of natural competence machinery. Thus, we hypothesize that P. melaninogenica natural competence can serve as a model to break the genetic tractability barrier within the Prevotella genus and reveal the genetic basis for its natural competence ability. The goals of this project will be achieved in two Specific Aims that: 1) characterize the natural competence ability of oral Prevotella and 2) develop a complete genetic toolbox for detailed genetic studies of oral Prevotella. Project Number: 1R21DE034151-01A1 | Fiscal Year: 2025 | NIH Institute/Center: National Institute of Dental and Craniofacial Research (NIDCR) | Principal Investigator: Justin Merritt | Institution: OREGON HEALTH & SCIENCE UNIVERSITY, PORTLAND, OR | Award Amount: $234,000 | Activity Code: R21 | Study Section: Oral, Dental and Craniofacial Sciences Study Section[ODCS] View on NIH RePORTER: https://reporter.nih.gov/project-details/11138198