Dmitri Mavrodi, Ph.D.

Assistant Professor, Department of Biological Sciences

I am a molecular microbiologist who is interested in the ecology of antibiotic-producing and plant-associated bacteria. The first line of my research is focused on the functional role of natural antibiotics. It has long been assumed that the primary function of these metabolites is to directly suppress competitors and yield a survival advantage to the producing bacteria in highly competitive natural and man-made environments. Recent studies suggest that antibiotics may promote virulence, protect bacteria from predation by protozoa, and act as molecular signals that regulate colony morphology and biofilm formation. However, most of these functions have been studied only under lab conditions and in a handful of bacterial strains. I use molecular techniques to better understand the ecological role of antibiotics in both pathogenic and beneficial bacteria in the context of microbial communities. The second line of my research is focused on beneficial plant root colonizing (rhizosphere) bacteria. These microorganisms play an important role in nature by protecting wild and crop plants from soilborne pathogens. They also stimulate nutrient uptake and organ development thus enhancing the ability of plants to resist abiotic stress factors. We have sequenced the genomes of several species of rhizosphere Pseudomonas bacteria. We plan to use tools of molecular genetics, functional genomics, and bioinformatics to identify cellular pathways and physiological responses that allow these beneficial rhizobacteria to maintain tight mutualistic interactions with the host plant under the conditions of environmental stress.

Selected recent publications:
1) Henkels MD, Kidarsa TA, Shaffer BT, Goebel NC, Burlinson P, Mavrodi DV, Bentley MA, Rangel LI, Davis EW, Thomashow LS, Zabriskie TM, Preston GM, and Loper JE (2014) Pseudomonas protegens Pf-5 causes discoloration and pitting of mushroom caps due to the production of antifungal metabolites. Mol Plant-Microbe Interact 27: 733-746
2) Mavrodi DV, and Parejko JA. Phenazines and biofilms. pp 71–88. In: S Chincholkar and L Thomashow (eds). Microbial phenazines. Springer-Verlag Berlin Heidelberg, Germany, 2013
3) Stockwell VO, Davis EW, Carey A, Shaffer BT, Mavrodi DV, Hassan KA, Hockett K, Thomashow LS, Paulsen IT, and Loper JE (2013) pA506, a conjugative plasmid of the plant epiphyte Pseudomonas fluorescens A506. Appl Environ Microbiol 79: 5272-5282
4) Mavrodi DV, Parejko JA, Mavrodi OV, Kwak Y-S, Weller DM, Blankenfeldt W, and Thomashow LS (2013) Recent insights into the diversity, frequency and ecological roles of phenazines in fluorescent Pseudomonas spp. Environ Microbiol 15: 675-686
5) Mavrodi DV, Mavrodi OV, Parejko JA, Bonsall RF, Kwak Y-S, Paulitz TC, Thomashow LS, and Weller DM (2012) Accumulation of the antibiotic phenazine-1-carboxylic acid in the rhizosphere of dryland cereals. Appl Environ Microbiol 78: 804-812
6) Loper JE, Hassan KA, Mavrodi DV, Davis EW, Lim CK, et al. (2012) Comparative genomics of plant-associated Pseudomonas spp: insights into diversity and inheritance of traits involved in multitrophic interactions. PLoS Genetics 8: e1002784
7) Parejko JA, Mavrodi DV, Mavrodi OV, Weller DM, and Thomashow LS (2012) Population structure and diversity of phenazine-1-carboxylic acid producing fluorescent Pseudomonas spp. from dryland cereal fields of central Washington State (USA). Microbial Ecol 64: 226-241
8) Mavrodi DV, Joe A, Mavrodi OV, Hassan KA, Weller DM, Paulsen IT, Loper JE, Alfano JR, and Thomashow LS (2011) Structural and functional analysis of the type III secretion system from Pseudomonas fluorescens Q8r1-96. J Bacteriol 193: 177–189
9) Mavrodi DV, Peever TL, Mavrodi OV, Parejko JA, Raaijmakers JM, Lemanceau P, Mazurier S, Heide L, Blankenfeldt W, Weller DM, and Thomashow LS (2010) Diversity and evolution of the phenazine biosynthesis pathway. Appl Environ Microbiol 76: 866–879
10) Mavrodi DV, Loper JE, Paulsen IT, and Thomashow LS (2009) Mobile genetic elements in the genome of the beneficial rhizobacterium Pseudomonas fluorescens Pf-5. BMC Microbiol 9: 8
11) Caldwell CC, Chen Y, Goetzmann HS, Hao Y, Borchers MT, Hassett DJ, Young LR, Mavrodi D, Thomashow L, and Lau GW (2009) Pseudomonas aeruginosa exotoxin pyocyanin causes cystic fibrosis airway pathogenesis. Am J Pathol 175: 2473–2488
12) Mavrodi OV, Mavrodi DV, Thomashow LS, and Weller DM (2007) Quantification of 2,4-diacetylphloroglucinol-producing Pseudomonas fluorescens in the plant rhizosphere by real-time PCR. Appl Environ Microbiol 73: 5531–5538