Photo of Dr. Paul Orwin

Dr. Paul Orwin



B.S., Harvey Mudd College
Ph.D., University of Minnesota


BIOL 220 - Principles of Microbiology
BIOL 492 - Recombinant DNA Techniques
BIOL 320 - Microorganisms

Research Interests:

Behavior of Variovorax paradoxus on surfaces

Variovorax paradoxus is a soil microorganism associated with many vital biological transformations, including remediation of toxic compounds and promotion of plant growth. It has a tremendous variety of metabolic capacities, including heterotrophic growth on a large number of carbon sources, and lithoautotrophic growth using hydrogen gas and carbon dioxide as sources of energy and carbon, respectively. Our lab has focused on a critical component of soil survival and success, the ability to attach to and move on surfaces. The surface attached sessile phase, biofilm formation, is a crucial and widespread bacterial lifestyle, associated with virulence as well as environmental growth under many conditions. Swarming motility is a mechanism of bacterial movement on a surface that involves a number of cell surface appendages as well as production of a wetting agent and a hygroscopic matrix. The combination of surface attachment and motility, and the decision to move or "put down roots" is a crucial determinant of success in the heterogeneous soil environment. Our overall goal is to understand the structural components that underlie these two phenotypes, and the regulatory circuits that control these decisions.

Representative Publications:

Baquiran JP, Thater B, Sedky S, De Ley P, Crowley D, and Orwin, PM. 2013. Culture-Independent Investigation of the Microbiome Associated with the Nematode Acrobeloides maximus. PloS one, 8(7): e67425.

Han J-I, Spain JC, Leadbetter JR, Ovchinnikova G, Goodwin LA, Han CS, Woyke T, Davenport KW, and Orwin PM. 2013. Genome of the Root-Associated Plant Growth-Promoting Bacterium Variovorax paradoxus Strain EPS. Genome Announcements, 1(5): e00843-13.

Pehl MJ, Jamieson WD, Kong K, Forbester JL, Fredendall RJ, Gregory GA, McFarland JE, Healy JM, and Orwin PM. 2012. Genes that influence swarming motility and biofilm formation in Variovorax paradoxus EPS. PloS one, 7(2): e31832.

Han JI, Choi HK, Lee SW, Orwin PM, Kim J, LaRoe SL, Kim T-G, O'Neil J, Leadbetter JR, Lee SY, Hur, C-G, Spain JC, Ovchinnikova G, Goodwin L, and Han C. 2011. Complete Genome Sequence of the Metabolically Versatile Plant Growth-Promoting Endophyte Variovorax paradoxus S110. Journal of Bacteriology, 193(5), 1183-1190.

Schottel JL, Orwin PM, Anderson CR, and Flickinger MC. 2008. Spatial Expression of a Mercury-Inducible Green Fluorescent Protein within a Nanoporous Latex-Based Biosensor Coating. Journal of Industrial Microbiology and Biotechnology, 35(4), 283-290.

Orwin PM, Fitzgerald JR, Leung DY, Gutierrez JA, Bohach GA, and Schlievert PM. 2003. Characterization of Staphylococcus aureus Enterotoxin L. Infection and Immunity, 71(5), 2916-2919.

Orwin PM, Leung DYM, Tripp TJ, Bohach GA, Earhart CA, Ohlendorf DH, and Schlievert PM. 2002. Characterization of a Novel Staphylococcal Enterotoxin-like Superantigen, a Member of the Group V Subfamily of Pyrogenic Toxins. Biochemistry, 41. 14033-14040.

Yarwood JM, McCormick JK, Paustian ML, Orwin PM, Kapur V, Schlievert PM. 2002. Characterization and Expression Analysis of Staphylococcus aureus Pathogenicity Island 3. Implications for the Evolution of Staphylococcal Pathogenicity Islands. J Biol Chem. 2002 Apr 12;277(15):13138-47.

Orwin PM, Leung DYM, Donahue HL, Novick RP, and Schlievert PM. 2001. Biochemical and Biological Properties of Staphylococcal Enterotoxin K. Infect. Immun. 69. 360-366.