St. Mary's University 1 Camino Santa MariaSan Antonio, TX 78228 +1-210-436-3011 St. Mary's University logo William Joseph Chaminade St. Mary's University, Texas

Larissa Walker, Ph.D.

Assistant Professor of Biological Sciences  | Forensic Science Specialist




  • Ph.D., Auburn University
  • B.S., William Carey University
  • B.A., William Carey University


Larissa Walker, Ph.D., is an Assistant Professor of Biological Sciences and directs the Forensic Science programs in Biology and Chemistry. She joined St. Mary's after working several years as a science writer with recent teaching positions at the University of Texas at San Antonio and Trinity University.

Walker's research is at the intersection of biochemistry and metagenomics, an emerging approach to studying the genetics of organisms at the community level. She has been awarded NSF and NIH fellowships to explore the ecological and physiological diversity of environmental microbes, especially with respect to natural product discovery and the spread of antibiotic resistance. More recently, she focused her attention on how microbes modify or degrade illicit drugs in and around the human body during the postmortem interval, which can obscure the time, cause and manner of death during forensic investigations.

Walker attributes her positive experiences to her undergraduate liberal arts education, which include a B.S. in Biology and a B.A. in English. Close interactions with faculty who helped her grow both scientifically and personally motivated her to be a dedicated mentor and role model to her own students. She encourages students to make connections with professors from all departments because this provides unique networking opportunities and an appreciation for how other disciplines complement science.

When not teaching or performing research, Walker regularly reviews textbooks published by McGraw Hill and Jones & Bartlett, and works as a consulting editor for universities and laboratories preparing for accreditation.

At St. Mary's, she is a FAM Program faculty mentor and is involved with Forensic Science curriculum development.


*Indicates undergraduate researcher
All publications are cited under maiden name (LC Parsley).

Parsley, LC, Linneman, J, Goode, AM, Becklund, K*, George, I, Linneman, J, Goodman, RM, Lopanik, N, and Liles, MR (2011). “Polyketide synthases identified from an arrayed metagenomic library are derived from soil Acidobacteria.” FEMS Microbiology Ecology 78(1):176-87.

Kakirde, KS, Parsley, LC, and Liles, MR (2010). “Size does matter: Application-driven approaches for soil metagenomics. Soil Biology and Biochemistry 42(11):1911-1923.

Parsley, LC and Liles, MR. (2010). “Fluorescence in situ hybridization of bacterial cell suspensions.” Cold Spring Harbor Press Protocols. Sep. 2010 (9):pdb.prot5493. doi:10.1101/pdb.prot5493.

Parsley, LC, Consuegra, EJ, Land, AM*, Kakirde, KS, Harper, WF Jr., and Liles, MR. (2010). “Discovery of diverse antibiotic resistance determinants from bacterial, plasmid, and bacteriophage metagenomes in an activated sludge community.” Applied and Environmental Microbiology 76(11): 3753-3757.

Parsley, LC, Consuegra, EJ, Thomas, SJ*, Bhavsar, J, Land, AM*, Bhuiyan, NN*, Mazher, MA*, Waters, RJ*, Wommack, KE, Harper, WF, and Liles, MR. (2010). “Census of the viral metagenome in an activated sludge microbial assemblage.” Applied and Environmental Microbiology 76(8): 2673-2677.

Parsley, LC, Wu, CC, Goodman, RM, and Liles, MR (2010). “Soil microbial DNA purification strategies for multiple metagenomic applications.” In Handbook of Molecular Microbial Ecology II: Metagenomics in Different Habitats. de Bruijn, F (ed). Wiley Publishing: Hoboken, NJ.

Liles, MR, Williamson, LL, Rodbumrer, J, Torsvik, V, Parsley, LC, Goodman, RM, and Handelsman, J (2009). “Isolation and cloning of high molecular metagenomic DNA from soil microorganisms.” Cold Spring Harbor Press Protocols. Aug. 2009 (8):pdb.prot5271. doi:10.1101/pdb.prot5271.

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