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Melissa Marks

Associate Professor of Biology; Department Chair

Headshot of Melissa Marks

Contact Information

Salem Campus

Olin Science Center 118
900 State Street
Salem  Oregon  97301
503-375-5425 (Fax)


  • Ph.D., Developmental Biology, Stanford University, Stanford, California
  • B.A., Biology, Grinnell College, Grinnell, Iowa

Teaching Philosophy

My teaching philosophy is comprised of three fairly simple, yet broad, tenets. First and foremost, students of all ages and ability levels learn by doing. This straightforward idea embodies my approach to science education. I believe that students learn, understand, and remember best when they confront real scientific problems both in and outside of the laboratory. It is important to remember that scientific “facts” were once unknown and that the observations and investigations of curious people continuously revise and expand our knowledge of life on Earth. Secondly, communication skills are essential. Proficiency in written and oral communication forms a foundation upon which scholars build throughout their lives, within both science and society. Finally, young scientists must develop a deep understanding the role of humanity and scientific ethics. Through participation in my courses or research program, students gain a better appreciation of the beauty and intricacy of life processes as well as the role humanity plays in the natural world.

Research Interests

The biology of an organism consists of intricately interwoven aspects that we must consider if we are to truly understand it. It is with a willingness to let the organisms inform the direction of the research that I approach my projects. My research concerns the genetics, ecology, and evolution in populations of aquatic bacteria (Caulobacter crescentus). As a postdoctoral fellow, I used next-generation sequencing technology to comprehensively map the genetic basis of all the known phenotypic differences between two strains of the nonpathogenic freshwater bacterium Caulobacter crescentus that have adapted to life in the laboratory environment. Since its initial isolation, C. crescentus has been cultured in laboratories throughout the world, accumulating phenotypic differences, including changes in susceptibility to bacteriophage, growth rate and lifespan, conferred through multiple genetic mechanisms. In the lab, we are currently working to quantify the role of glucose-6-phosphate dehydrogenase (zwf) expression on growth rate, characterize the interaction between C. crescentus and the bacteriophage CR30, map the genetic basis of bacteriophage susceptibility, biochemically characterize the C. crescentus exopolysaccharide (EPS) layer, and dissect the relationship between nutrient transport and lifespan.


  • Herr KL§, Carey AM, Heckman TI, Chávez JL, Johnson CN, Harvey E, Gamroth WA§, Wulfing BS§, Van Kessel RA§, and Marks ME. 2018. Exopolysaccharide production in Caulobacter crescentus: a resource allocation trade-off between protection and growth. PLOS ONE 13:e0190371.
         *These authors contributed equally to this work
       #These authors contributed equally to this work
       §Willamette University Undergraduate Student
  • Rogers SM, Tamkee P, Summers B, Balabahadra S, Marks M, Kingsley DM, Schluter D. (2012) Genetic signature of adaptive peak shift in threespine stickleback. Evolution 66:2439–2450.
  • Marks ME, Castro Rojas CM, Perbost C, Du L, Walnus T, Kapatral V and Crosson S. (2010) The genetic basis of laboratory adaptation in Caulobacter crescentus. Journal of Bacteriology: 192(14): 3678-88.
  • Shapiro MD*, Marks ME*, Peichel CL*, Blackman BK, Nereng KS, Jonsson B, Schluter D, Kingsly DM. (2004). Genetic and developmental basis of evolutionary pelvic reduction in threesprine sticklebacks. Nature: 428(6984): 717-723. (*co-first authors)
  • Rountree RB, Schoor M, Chen H, Marks ME, Harley V, Mishina Y, Kingsley DM. (2004) BMP receptor signaling is required for postnatal maintenance of articular cartilage. PloS Biology: 2(11): 1815-1827
  • Herbet JM, Hayhurst M, Marks ME, Kulessa H, Hogan BL, McConnell SK. (2003) BMP ligands act to pattern the dorsal telencphalic midline. Genesis 35(4):214-9.
Willamette University

Biology Department

Willamette University
900 State Street
Salem Oregon 97301 U.S.A.
503-375-5425 fax