Dr. Evan G. Johnson

Contact Information

Citrus Research and Education Center
Lake Alfred, Florida
Plant Pathology
Phone: 863.956.1151 ext. 1371
Email: egjohnson@ufl.edu

Education

Ph.D. Plant Pathology Aug 2007 major: Molecular Plant Pathology minors: Microbiology and Chemical Biology

Dissertation title: Biosynthesis of Plant Cell Wall-Induced Thaxtomin and Nitric Oxide by Plant-Pathogenic Streptomyces Spp. Coadvisors: Rosemary Loria, Donna M. Gibson

B.A. May 2001 majors: Biology, Chemistry. Wabash College, Crawfordsville, IN

Positions

2008-present – Post-doc, Citrus Research and Education Center, Uiniversity of Florida, Lake Alfred, FL.

2007 – Research Intern, Vybion Inc. Ithaca, NY.

2001-2007 – Graduate Research Assistant/Teaching Assistant/Research Fellow, Department of Plant Pathology, Cornell University, Ithaca, NY.

2000-01 – Undergraduate Teaching Assistant, Quantitative skills center, Chemistry, Wabash College, Crawfordsville, IN.

1999-2000 – Undergraduate Research Intern, Department of Chemistry, Wabash College, Crawfordsville, IN.

1997 – Summer research assistant, US Forest Service, Intermountain Fire Sciences Laboratory, Missoula, MT.

Specialization

Molecular Plant Pathology, Secondary Metabolism

Ongoing Research

Colonization and survival of Xanthomonas axonopodis pv. citri, the causal agent of citrus canker, on citrus fruit and leaves.

Determination of the temporal effects of different cropping systems of tomato on the diversity of the arbuscular mycorrhizal fungal (AMF) community in soils in subtropical environments.

Refereed Publications

R. Loria, D. R. Bignell, S. Moll, J. C. Huguet-Tapia, M. V. Joshi, E. G. Johnson, R. F. Seipke, D. M. Gibson.  2008.  Thaxtomin biosynthesis: The path to plant pathogenicity in the genus Streptomyces.  Antonie van Leeuwenhoek International Journal of General and Molecular Microbiology, DOI 10.1007/s10482-008-9240-4.

E. G. Johnson, J. P. Sparks, B. Dzikovski, B. R. Crane, D. M. Gibson, R. Loria.  2008.  Plant-pathogenic Streptomyces species produce nitric oxide synthase derived nitric oxide in response to host signals.  Chemistry and Biology, 15(1):43-50.

E. G. Johnson, M. V. Joshi, D. M. Gibson, R. Loria.  2007.  Cello-oligosaccharides released from host plants induce pathogenicity in scab-causing Streptomyces species.  Physiological and Molecular Plant Pathology, 71:18-25.

M. V. Joshi, D. R. D. Bignell, E. G. Johnson, Jed P. Sparks, D. M. Gibson, R. Loria.  2007.  The AraC/XylS regulator TxtR modulates thaxtomin biosynthesis and virulence in Streptomyces scabies.  Molecular Microbiology, 66:633-642.

Professional Memberships

• 2002 – Present: American Phytopathologica Society
• 2005 – Present: International Society of Molecular Plant-Microbe Interactions