The main goal of my research program is to understand the role of microbes in ecosystem functioning, with ecosystems ranging from soils to processed food products to the human gut. I currently conduct studies examining how fermentation of plant foods affects composition and bioavailability of phytochemicals beneficial for human health. Focus plants include rice bran and fermented Chinese tea, both of which have been used traditionally as medicines in Asian cultures and have shown activity in a number of chronic and infectious disease models. Another area of study is how dietary phytochemicals affect the composition of gut microbes. Our native microflora protects against pathogen infection, aids in digestion of dietary components to contribute to host energy status, and influences mucosal and systemic immune development. Thus, the ability to manipulate the gut microbiota through diet is a viable disease prevention strategy. I have focused my recent research efforts on identifying the inter-relationships between diet, microflora, and microbial metabolism to gain a better understanding of their underlying mechanisms. These studies have been highly interdisciplinary research efforts conducted in collaboration with Dr. Elizabeth Ryan (CSU-Clinical Sciences) and Dr. Melissa Wdowik (CSU-Food Science and Nutrition).
Ph.D. (2008): Cell and Molecular Biology. Colorado State University, Fort Collins, CO.
Dissertation: Interactions between plants and the human opportunistic pathogen, Pseudomonas aeruginosa.
M.Sc. (1997): Plant pathology. Pennsylvania State University, State College, PA.
Thesis: Investigation of the genetic variability in the fungal pathogens, Alternaria solani and Alternaria alternata.
B.S. (1995): Biology-Genetics and Development/Minor-Microbiology. Pennsylvania State University, State College, PA.
08/2011-current: Assistant Professor, Dept. of Food Science and Nutrition, Colorado State University
10/2008-7/2011: Assistant Professor, Dept. of Horticulture, Colorado State University
8/2007-8/2008: Visiting Scientist, Institute of Environmental Studies, Pontifical Catholic University of Peru, Lima, Peru.
9/2002-8/2007: Research Associate, Dept. of Horticulture, Colorado State University
9/2002-11/2003: Risk analyst, USDA, APHIS, PPQ-Fort Collins, CO
7/1998-8/2002: Plant Protection Officer, USDA, APHIS, PPQ-Jamaica, NY/Aurora, CO
9/1994-5/1995: Research Assistant, Dept. of Plant Pathology, Pennsylvania State University
5-8/1994: Research Assistant, Dept. of Entomology, Pennsylvania State University
9/1993-5/1994: Research Assistant, Dept. of Plant Pathology, Pennsylvania State University
2008-present Consultant for El Pedregal, Agricola Chapi, Pantanos de Villa, INIA, USDA-FAS, Denver Diabetes Foundation, Golden Flower Trading Company
2009-present Peace Corp Master’s International, Horticulture Advisor
2009-present Conducting clinical trials at Poudre Valley Hospital in collaboration with the Depts. of Food Science and Nutrition and Clinical Sciences.
2009-present Member of American Society of Microbiology
2011 Member of the Phytochemical Society of North America
2011 Member of the Association of Tropical Biology and Conservation
4/2010 Conducted HPLC training workshop for Peruvian government officials
2010-present CSU representative for Western Association of Agricultural Experiment Station Directors project W2122
2011 Initiated and implemented IMOU with Hunan Agricultural University, Changsha, China
Xu X, Hu Y, Xiao W*, Weir TL*, Ryan EP, Huang J, He X, Wu J (2011) Effects of Fu Brick Tea consumption on the production performance, egg traits and the lipid metabolism in laying hens. J Agric. Food Chem. Under review.
Barnett BA and Weir TL* (2011) Bacterial secretion. In: Secretions and Exudates in Biological Systems (eds. Baluska F, Vivanco JM). Springer, Berlin, Germany. In press.
Kumar A, Duffy A, Forster G, Goodyear AW, Weir TL, Leach JE, Dow S, Ryan EP (2011) Dietary rice bran reduces susceptibility to Salmonella enteric Typhimurium infection in mice. PLOS Medicine. Under review
Weir TL*, Hu Y, Ryan EP, Lin W, Murray P, Fu D, Snook R, Xiao W. (2011) Medicinal teas: a review to summarize health benefits and highlight fermented tea. Herbalgram. Under review.
Fu D, Ryan EP, Huang J, Liu Z, Weir TL, Snook R, Ryan T (2011) Fermented Camellia sinensis, Fuzhuan Tea, regulates hyperlipidemia and transcription factors involved in lipid catabolism. Food Research International. In press.
Ryan EP, Heuberger AL, Weir TL, Barnett BA, Broeckling CD, Prenni JE (2011) Rice bran fermented with Saccharomyces boulardii generates novel metabolite profiles with bioactivity. J Food Agric Chem. 59, 1862-1870.
Weir TL, Newbold TAS, Vivanco JM, van Haren M, Fritchman C, et al. (2011) Plant Inhabiting Ant, Pseudomyrmex triplarinus, utilizes chemical cues for host discrimination. Biotropica. 43, DOI 10.1111/j.1744-7429.2011.00786.x
Weir TL, Manter DM, Kofer W. (2011) Microbes: A new frontier in tropical chemical biology. In: Chemical Biology of the Tropics: An interdisciplinary approach. (eds. Vivanco JM, Weir TL). Springer, Berlin, Germany. Pp114
Manter DK, Weir TL, Vivanco JM (2010) Sample pooling masks PCR-based estimates of soil microbial richness and community structure. Appl. Environ. Microbiol. 76, 2086-2090.
Badri D, Weir TL, van der Lelie D, Vivanco JM (2009) Rhizosphere chemical dialogues: plant–microbe interactions. Curr. Opin. Biotech. 20, 642-650.
Weir TL, Stull VJ, Badri D, et al. (2008) Examination of global gene expression suggests an important role for nutrient acquisition in early pathogenesis in a Pseudomonas aeruginosa-plant infection model. Appl. Environ. Microbiol. 74: 5784-5791.
Weir TL, Vivanco JM (2008) Allelopathy: Full circle from phytotoxicity to methods of resistance. In: Allelopathy in sustainable agriculture and forestry. Zeng RS, Luo SM, Malick A (eds.) Springer-Verlag, Berlin Heidelberg.
Weir TL* (2007) The role of allelopathy and mycorrhizal associations in biological invasions. Allelopathy J 20:43-50.
Weir TL, Bais HP, Stull VJ et al (2006) Oxalate contributes to the resistance of Gaillardia grandiflora and Lupinus sericeus to a phytotoxin produced by Centaurea maculosa. Planta 223: 785-795.
Weir TL, Perry LG, Vivanco JM (2006) Phytoxins produced by invasive weeds and their applications in agriculture and the restoration of natural areas. In Natural Products for Pest Management (Rimando, A. M. and S.O. Duke, eds.). Symposium Series No. 927. Washington, D.C.: American Chemical Society, pp 99-112.
Prithiviraj B, Bais HP, Weir TL, et al (2005) Down regulation of virulence factors of Pseudomonas aeruginosa by salicylic acid attenuates its virulence on Arabidopsis thaliana and Caenorhabditis elegans. Infect. Immun. 73: 5319-5328.
Prithiviraj B*, Weir TL*, Bais HP, Schweizer HP, Vivanco JM (2005) Plant models for animal pathogenesis. Cell. Microbiol.7: 315-324.
CSU Infectious Disease Supercluster; Investigation of antimicrobial activity by fermented tea extracts: implications for novel therapeutics. $25K, 7/2011-6/2012.
Colorado Wheat Research Foundation; Interactions between winter wheat and ACC deaminase positive bacteria in relation to drought tolerance. $10K, 2010-2011.
Denver Diabetes Foundation/Golden Flower Trading Company. Foundation gift ~$88K 2011.
NIH-NCI; Probiotic metabolism of rice bran for cancer prevention, $157K, 2010-2012
Pending Support:
USDA-NIFA Foundational Program, $400K, submitted 6/2011
National Pork Board; Natural feed additives to increase feed efficiency and reduce Salmonella typhimurium fecal shedding in pigs. $40K, submitted 5/2011.
NIH-NCI R21; Microbial Metabolism of Rice Bran for Colon Cancer Prevention. $250K, submitted 6/2011.
AGRI 692-International Agricultural Systems, Spring 2010
H792- Horticulture Seminar Series, Spring 2007
Hort 480-Medicinal and value added uses of plants, Spring 2007, 2003
Hort 580- Topics in Rhizosphere Biology, Spring 2006