Please note: The University of Texas Health Science Center at San Antonio will now be called "UT Health San Antonio."

Search Program Faculty/Research

Joel B. Baseman, Ph.D.

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Dr. Joel Baseman's lab studies the biology of Mycoplasma pneumoniae (MPN) and relate these studies to airway disease pathogenesis in humans and animal models. Their recent discovery of the Community-Acquired Respiratory Distress Syndrome (CARDS) toxin of MPN represents the first authentic virulence factor found in MPN, as the toxin behaves as a bona fide ADP-ribosylating (ADPR) toxin (like the classical ADPR toxins of pertussis and diphtheria) and vacuolating toxin (like VacA). They have compelling clinical evidence that CARDS TX is responsible for mediating acute and chronic airway diseases, including asthma.

They also examine the sexually transmitted mycoplasma, Mycoplasma genitalium (MGN) and are clarifying MGN virulence determinants that mediate the dynamic interactions between MGN and human target cells, leading to overt clinical disease. 

Selected Publications

Kannan, T.R., M. Krishnan, R. K. Ramasamy, A. Becker, O.N. Pakhomova, P.J. Hart, and J.B. Baseman. 2014. Functional mapping of community acquired respiratory distress syndrome (CARDS) toxin of Mycoplasma pneumoniae defines regions with ADP-ribosyltransferase, vacuolating, and receptor-binding activities. Mol. Microbiol. 93(3):568-81. PMID: 

Medina, J., J.J. Coalson, E.G. Brooks, C.J. LeSaux, V.T. Winter, A. Chaparro, M.F.R. Principe, L. Solis, T.R. Kannan, J.B. Baseman and P. Dube. 2014. Mycoplasma pneumoniae CARDS toxin exacerbates ovalbumin-induced asthma-like inflammation in BALB/c mice. PLoS One 9(7):e102613. 

Somarajan, S.R, F. Al-Asadi, K. Ramasamy, L. Pandranki, J.B. Baseman and T.R. Kannan. 2014. Annexin A2 mediates Mycoplasma pneumoniae CARDS toxin binding to eukaryotic cells.MBio 5(4):e01497-1514.

Bose, S., J.A. Segovia, S.R. Somarajan, T-H Chang, Kannan, T.R. and J.B. Baseman. 2014. ADP-ribosylation of NLRP3 by Mycoplasma pneumoniae CARDS toxin regulates inflammasome activity. MBio 23;5(6): e02186-14. 

Becker, A., T.R. Kannan, A.B. Taylor, O.N. Pakhomova, Y. Zhang, J. Jiang, S.R. Somarajan, A. Galaleldeen, S.P. Holloway, B. Demeler, J.B. Baseman and P.J. Hart. 2015. Structure of CARDS toxin, a unique ADP-ribosylating and vacuolating cytolating cytotoxin from Mycoplasma pneumoniae. Proc. Nat. Acad. Sci.;published ahead of print April 6, 2015, doi:10.1073/pnas.1420308112. 

Zhang W, Baseman JB. Functional Characterization of Osmotically Inducible Protein C (MG_427) from Mycoplasma genitalium. J Bacteriol. 2014 Mar;196(5):1012-9. 

Krishnan M, Kannan TR, Baseman JB. Mycoplasma pneumoniae CARDS toxin is internalized via clathrin-mediated endocytosis. PLoS One. 2013 May 7;8(5):e62706.

Kannan TR, Hardy RD, Coalson JJ, Cavuoti DC, Siegel JD, Cagle M, Musatovova O, Herrera C, Baseman JB. Fatal outcomes in family transmission of Mycoplasma pneumoniae. Clin Infect Dis. 2012 Jan 15;54(2):225-31.

Kannan TR, Coalson JJ, Cagle M, Musatovova O, Hardy RD, Baseman JB. Synthesis and distribution of CARDS toxin during Mycoplasma pneumoniae infection in a murine model. J Infect Dis. 2011 Nov 15;204(10):1596-604.

Peters J, Singh H, Brooks EG, Diaz J, Kannan TR, Coalson JJ, Baseman JG, Cagle M, Baseman JB. Persistence of community-acquired respiratory distress syndrome toxin-producing Mycoplasma pneumoniae in refractory asthma. Chest. 2011 Aug;140(2):401-7. doi: 10.1378/chest.11-0221.

Microbiology, Immunology, and Molecular Genetics 


Ph.D., Microbiology, University of Massachusetts, 1968

M.S., Microbiology, University of Massachusetts, 1965

B.S., Biology/Chemistry, Tufts University, 1963



Phone: (210) 562-4190

Research Profile
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