| |
Linda
S. Thomashow
.jpg) 509-335-0930
thomasho@mail.wsu.edu
USDA-ARS Research
Geneticist and adjunct to the Molecular Plant Sciences and the
Departments of Microbiology and Plant Pathology. Ph.D. 1979,
UCLA.
Research
Certain
beneficial strains of fluorescent Pseudomonas bacterial species
colonize the roots of plants and provide biological control
of soilborne plant pathogens through the production in situ of
small organic molecules with antibiotic activity. One focus
of our research is to understand the genetics, biochemistry,
and regulation of synthesis of two classes of these metabolites,
phenazine and phloroglucinol compounds, with the goal of improving
the level and consistency of performance of the biocontrol agents
that produce them. Because these bacteria must deliver the antibiotics
to sites on roots impacted by fungal pathogens, we also are
working to understand the genetic and physiological basis for
a particularly aggressive root colonization phenotype exhibited
by some of our strains. Finally, because we have engineered
multiple antibiotic biosynthesis pathways and biocontrol mechanisms
into some of our most aggressive root colonizers, we are studying
the effects of these bacteria on their plant hosts and other,
nontarget plant-associated microorganisms.
Selected
Publications
Mavrodi, D. V., Blankenfeldt, W., and Thomashow, L. S. 2006. Phenazine
compounds in fluorescent Pseudomonas spp: Biosynthesis and regulation.
Annu. Rev. Phytopathol. (in press).
Khan, S. R., Mavrodi D. V., Jog, G. J., Suga, H., Thomashow, L.
S., and Farrand, S. K. 2005. Activation of the phz operon of Pseudomonas
fluorescens 2-79 requires the LuxR homolog PhzR, N-(3-OH-hexanoyl)-L-homoserine
lactone produced by the LuxI homologue PhzI, and a cis-acting phz-box.
J. Bacteriol. 187: 6517-6527.
Validov, S., Mavrodi, O., De La Fuente, L., Boronin, A., Weller,
D., Thomashow, L., and Mavrodi, D. 2005. Antagonistic activity
among 2,4-diacetylphloroglucinol-producing fluorescent Pseudomonas
spp. FEMS Microbiol. Lett. 242:249-256.
Paulsen, I.T., Press, C., Ravel, J., Kobayashi, D. Y., Myers,
G. S. A., Mavrodi, D. V., DeBoy, R.T., Seshadri, R., Ren, Q., Madupu,
R., Dodson, R. J., Durkin, A. S., Brinkac, L. M., Daugherty, S.
C., Sullivan, S. A., Rosovitz, M. J., Gwinn, M. L., Zhou, L., Nelson,
W. C., Weidman, J., Watkins, K., Tran, K., Khouri, H., Pierson,
E. A., Pierson, L. S., Thomashow, L. S., and Loper, J. E. 2005.
Complete genome sequence of the plant commensal Pseudomonas fluorescens
Pf-5: insights into the biological control of plant disease. Nature
Biotechnology 23: 873-878.
Blankenfeldt, W., Kuzin, A. P., Skarina, T., Korniyenko, Y., Tong,
L., Bayer, P., Janning, P., Thomashow, L. S., and Mavrodi, D. V.
2004. Structure and function of phenazine biosynthesis protein
PhzF from Pseudomonas fluorescens 2-79. Proc. Natl. Acad. Sci.
U.S.A. 101:16431-16436.
Mavrodi, D. V., Bleimling, N., Thomashow, L. S., and Blankenfeldt,
W. 2004. The purification, crystallization and preliminary structural
characterization of PhzF, a key enzyme in the phenazine-biosyntheis
pathway from Pseudomonas fluorescens 2-79. Acta Crystallogr. D
60:184-186.
Huang, Z., Bonsall, R. F., Mavrodi, D. V., Weller, D. M., and
Thomashow, L. S. 2004. Transformation of Pseudomonas fluorescens
with genes for biosynthesis of phenazine-1-carboxylic acid improves
biocontrol of Rhizoctonia root rot and in situ antibiotic production.
FEMS Microbiol. Ecol. 49:243-251.
De La Fuente, L., Thomashow, L. S., Weller, D. M., Bajsa, N.,
Quagliotto, L., Chernin L., and Arias, A. 2004. Pseudomonas fluorescens
UP61 isolated from birdsfoot trefoil rhizosphere produces multiple
antibiotics and exerts a broad spectrum of biocontrol activity.
Eur. J. Plant Pathol. 110:671-681.
Ahuja, E. G., Mavrodi, D. V, Thomashow, L. S., and Blankenfeldt,
W. 2004. Overexpression, purification and crystallization of PhzA,
the first enzyme of the phenazine biosynthesis pathway of Pseudomonas
fluorescens 2-79. Acta Crystallogr. D 60:1129-1131.
Viebahn, M., Glandorf, D. C. M., Ouwens, T. W. M., Smit, E., Leeflang,
P., Wernars, K. Thomashow, L. S., van Loon, L. C., and Bakker,
P. A. H. M. 2003. Repeated introduction of genetically modified
Pseudomonas putida WCS358r without intensified effects on the indigenous
microflora of field-grown wheat. Appl. Environ. Microbiol. 69:3110-3118.
Mavrodi, D. V., N. Bleimling, L. S. Thomashow, and W. Blankenfeldt.
2003. The purification, crystallization and preliminary structural
characterization of PhzF, a key enzyme in the phenazine-biosynthetic
pathway from Pseudomonas fluorescens 2-79. Acta Cryst. D:60:184-186.
Denison,
R. F., D. Bledsoe, M. Kahn, F. O’Gara, E. L. Simms,
and L. S. Thomashow. 2003. Cooperation in the rhizosphere and the “free
rider” problem. Ecology. 84:838-845.
Landa, B.B., D. M. Mavrodi, L. S. Thomashow, and D. M. Weller.
2003. Interactions between strains of 2,4-diacetylphloroglucinol-producing
Pseudomonas fluorescens in the rhizosphere of wheat. Phytopathology.
93:982-994.
Raaijmakers, J. M., Weller, D. M., Thomashow, L. S., and Cook,
R. J. 2002. Biocontrol of take-all. United States Patent No. 6,447,770
B1.
Weller, D. M., J. M. Raaijmakers, B. B. McSpadden Gardener, and
L. S. Thomashow. 2002. Microbial populations responsible for specific
soil suppressiveness to plant pathogens. Annu. Rev. Phytopathol.
40:309-348.
Landa, B. B., Mavrodi, O. V., Raaijmakers, J. M., McSpadden Gardener,
B. B., Thomashow, L. S., and Weller, D. M. 2002. Differential ability
of genotypes of 2,4-diacetylphloroglucinol-producing Pseudo-monas
fluorescens strains to colonize the roots of pea plants. Appl.
Environ. Microbiol. 68:3226-3237.
Bakker, P.A.H.M., D.C.M. Glandorf, M. Viebahn, T.W.M. Ouwens,
E. Smit, P. Leeflang, K. Wernars, L.S. Thomashow, J.E. Thomas-Oates,
and L C. van Loon. 2002. Effects of Pseudomonas putida modified
to product phenazine-1-carboxylid acid and 2,4-diacetyl-phloroglucinol
on the microflora of field grown wheat. Antonie van Leeuwenhoek
81:617-624.
Mavrodi, D. V., O. V. Mavrodi, B. B. McSpadden-Gardener, B. B.
Landa, D. M. Weller, and L. S. Thomashow. 2002. Identification
of differences in genome content among phlD-positive Pseudomonas
fluorescens strains by using PCR-based subtractive hybridization.
Appl. Environ. Microbiol. 68:5170-5176.
Thomashow, L. S., Bonsall, R. F., and Weller, D. M. 2002. Antibiotic
production by soil and rhizosphere microbes in situ. Pages 636-647
in: Manual of Environmental Microbiology, 2nd Edition. C. J. Hurst,
R. L. Crawford, G. R. Knudsen, M. J. McInerney, and L. D. Stetzenbach,
eds. ASM Press, Washington, D.C. 1138 pp.
Weller, D.M., Raaijmakers, J.M., McSpadden, Gardener, B.B. and
Thomashow, L.S. 2002. Microbial populations responsible for specific
soil suppressiveness to plant pathogens. Annu. Rev. Phytopathol.
40:309-348.
Mavrodi, D.V., Bonsall, R.F., Delaney, S.M., Soule, M.J., Phillips,
G. and Thomashow, L.S. 2001. Functional analysis of genes for biosynthesis
of pyocyanin and phenazine-1-carboxamide from Pseudomonas aeruginosa
PAO1. J Bacteriol. 183:6454-6465.
McDonald, M., Mavrodi, D.V., Thomashow, L.S. and Floss, H.G. 2001.
Phenazine biosynthesis in Pseudomonas fluorescens: Branchpoint
from the primary shikimate biosynthetic pathway and role of phenazine-1,6-dicarboxylic
acid. J. Am. Chem. Soc. 123:9459-9460.
Glandorf, D.C.M., Verheggen, P., Jansen, T., Jorritsma, J. W.,
Smit, E., Leeflang, P., Wernars, K., Thomashow, L.S., Laureijs,
E., Thomas-Oates, J.E., Bakker, P.A.H.M. and van Loon, L.C. 2001.
Effect of genetically modified Pseudomonas putida WCS358r on the
fungal rhizosphere microflora of field-grown wheat. Appl. Envir.
Microbiol. 67:3371-3378.
Bangera, M.G. and Thomashow, L.S. 1999. Identification and characterization
of a gene cluster for synthesis of the polyketide antibiotic 2,4-diacetylphloroglucinol
from Pseudomonas fluorescens Q2-87. J. Bacteriol. 181:3155-3163.
Weller, D.M., Raaijmakers, J.M., McSpadden, Gardener, B.B. and
Thomashow, L.S. 2002. Microbial populations responsible for specific
soil suppressiveness to plant pathogens. Annu. Rev. Phytopathol.
40:309-348.
Mavrodi, D.V., Mavrodi, O.V., McSpadden-Gardener, B.B., Landa,
B.B., Weller, D.M. and Thomashow, L.S. 2002. Identi-
fication of differences in genome content among phlD-positive Pseudomonas
fluorescens strains by using PCR-based subtractive hybridization.
Appl. Environ. Microbiol. 68(10):5170-5176.
Mavrodi, D.V., Bonsall, R.F., Delaney, S.M., Soule, M.J., Phillips,
G. and Thomashow, L.S. 2001. Functional analysis of genes for biosynthesis
of pyocyanin and phenazine-1-carboxamide from Pseudomonas aeruginosa
PAO1. J Bacteriol. 183:6454-6465.
McDonald, M., Mavrodi, D.V., Thomashow, L.S. and Floss, H.G. 2001.
Phenazine biosynthesis in Pseudomonas fluorescens: Branchpoint
from the primary shikimate biosynthetic pathway and role of phenazine-1,6-dicarboxylic
acid. J. Am. Chem. Soc. 123:9459-9460.
Glandorf, D.C.M., Verheggen, P., Jansen, T., Jorritsma, J. W.,
Smit, E., Leeflang, P., Wernars, K., Thomashow, L.S., Laureijs,
E., Thomas-Oates, J.E., Bakker, P.A.H.M. and van Loon, L.C. 2001.
Effect of genetically modified Pseudomonas putida WCS358r on the
fungal rhizosphere microflora of field-grown wheat. Appl. Envir.
Microbiol. 67:3371-3378.
|
|
|
|
