Dietary fiber is an important carbon source for some of the most abundant species of the gut microbiota. In Bacteroidetes, gene clusters encoding protein systems necessary for metabolism of specific complex carbohydrates are colocalized into polysaccharide utilization loci, or PULs. Bacteroides thetaiotaomicron encodes 88 different PULs and their transcriptional expression is strictly regulated. In B. theta 32 PULs are regulated by an unusual class of TCSs known as Hybrid Two-Component Systems (HTCSs). In HTCSs, the transmembrane sensor histidine kinase and response regulator transcription factor of canonical TCSs are fused into a single polypeptide chain with extracellular ligand sensing, histidine autophosphorylation, phosphoryl transfer, and transcriptional regulation occurring within a single transmembrane dimer. Our studies focus on mechanistic characterization of phosphorylation and DNA binding of representative HTCS proteins. Structural characterization is being pursued by X-ray crystallography and cryo-EM. Cellular studies are aimed at defining the regulons of individual HTCSs and the coordination between HTCSs that determines preferential utilization of different dietary polysaccharides and host glycans.
Program Faculty
- Ann M. Stock
- Distinguished Professor
- Department: Department of Biochemistry and Molecular Biology
- Graduate Program(s): Biochemistry | Cell and Developmental Biology | Microbiology and Molecular Genetics
- Major Research Interest(s): Gene regulation, Microbiome, Signaling, Structural Biology
- Research Techniques: Atomic or Electron microscopy, Biochemistry, Fluorescent and super resolution microscopy, Protein Structure / Crystallography, Transcriptomics
- Research Organism(s): Bacteria, in vitro
- Phone: 1.8484459812
- Email:
This email address is being protected from spambots. You need JavaScript enabled to view it. - Robert Wood Johnson Medical School
- Center for Advanced Biotechnology and Medicine CABM, Room 338
- 679 Hoes Lane
- Piscataway, NJ 08854-5627
- Key Words: regulation of polysaccharide utilization by gut bacteria
- Lab Site URL
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