• B.S., 2001, Purdue University, Biochemistry.
  • Ph.D., 2006, The University of Chicago, Microbiology.
  • Postdoctoral research: Tufts University School of Medicine.

Joined the department in 2010.

Sorg Lab Website

Research Description

My lab is focused on the mechanisms of spore germination and bile acid resistance in Clostridium difficileC. difficile is a Gram-positive, spore forming, anaerobe that causes infections in people who have undergone antibiotic regimens.  Previously, we had shown that certain bile acids promote C. difficile spore germination while others inhibit germination.  Bile acids are small molecules made by the liver that help the absorption of fat and cholesterol in the GI tract while also serving as a protective barrier against invading pathogens.  Because C. difficile spores use the ratios of bile acids as cues for germination, the actively growing bacteria must have adapted means to avoid their toxic properties.  We are currently focused on identifying these factors and the mechanisms by which C. difficile spores germinate.

  1. Girinathan, BP, Monot, M, Boyle, D, McAllister, KN, Sorg, JA, Dupuy, B et al.. Effect of tcdR Mutation on Sporulation in the Epidemic Clostridium difficile Strain R20291. mSphere. ;2 (1):. doi: 10.1128/mSphere.00383-16. PubMed PMID:28217744 PubMed Central PMC5311115.
  2. Francis, MB, Sorg, JA. Dipicolinic Acid Release by Germinating Clostridium difficile Spores Occurs through a Mechanosensing Mechanism. mSphere. ;1 (6):. doi: 10.1128/mSphere.00306-16. PubMed PMID:27981237 PubMed Central PMC5156672.
  3. Bhattacharjee, D, McAllister, KN, Sorg, JA. Germinants and Their Receptors in Clostridia. J. Bacteriol. 2016;198 (20):2767-75. doi: 10.1128/JB.00405-16. PubMed PMID:27432831 PubMed Central PMC5038010.
  4. Francis, MB, Sorg, JA. Detecting Cortex Fragments During Bacterial Spore Germination. J Vis Exp. 2016; (112):. doi: 10.3791/54146. PubMed PMID:27403726 PubMed Central PMC4970447.
  5. Bhattacharjee, D, Francis, MB, Ding, X, McAllister, KN, Shrestha, R, Sorg, JA et al.. Reexamining the Germination Phenotypes of Several Clostridium difficile Strains Suggests Another Role for the CspC Germinant Receptor. J. Bacteriol. 2015;198 (5):777-86. doi: 10.1128/JB.00908-15. PubMed PMID:26668265 PubMed Central PMC4810609.
  6. Fimlaid, KA, Jensen, O, Donnelly, ML, Francis, MB, Sorg, JA, Shen, A et al.. Identification of a Novel Lipoprotein Regulator of Clostridium difficile Spore Germination. PLoS Pathog. 2015;11 (10):e1005239. doi: 10.1371/journal.ppat.1005239. PubMed PMID:26496694 PubMed Central PMC4619724.
  7. Bouillaut, L, McBride, S, Sorg, JA, Schmidt, DJ, Suarez, JM, Tzipori, S et al.. Effects of surotomycin on Clostridium difficile viability and toxin production in vitro. Antimicrob. Agents Chemother. 2015;59 (7):4199-205. doi: 10.1128/AAC.00275-15. PubMed PMID:25941230 PubMed Central PMC4468702.
  8. Francis, MB, Allen, CA, Sorg, JA. Spore Cortex Hydrolysis Precedes Dipicolinic Acid Release during Clostridium difficile Spore Germination. J. Bacteriol. 2015;197 (14):2276-83. doi: 10.1128/JB.02575-14. PubMed PMID:25917906 PubMed Central PMC4524186.
  9. Sorg, JA. Microbial bile acid metabolic clusters: the bouncers at the bar. Cell Host Microbe. 2014;16 (5):551-2. doi: 10.1016/j.chom.2014.10.015. PubMed PMID:25525784 PubMed Central PMC4977530.
  10. Paredes-Sabja, D, Shen, A, Sorg, JA. Clostridium difficile spore biology: sporulation, germination, and spore structural proteins. Trends Microbiol. 2014;22 (7):406-16. doi: 10.1016/j.tim.2014.04.003. PubMed PMID:24814671 PubMed Central PMC4098856.
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Joseph Sorg

Joseph Sorg
Associate Professor

3258 TAMU
College Station, TX 77843-3258

Biological Sciences Building East
Room 314C

Biological Sciences Building East
Room 316
Fax: 979-845-2891
Email: jsorg@bio.tamu.edu

Curriculum Vitae