Faculty & Research
- Contact Information
- Contact Yves Brun by ybrun [at] indiana [dot] edu
- By telephone: 812-855-8860/5-7239(lab)
- JH 447G / JH 447F (lab)
- Research Areas
- Genomics and Bioinformatics
- Microbial Cell Biology and Environmental Responses
- Microbial Interactions and Pathogenesis
Ph.D., Université Laval, Québec, Canada, 1990
Postdoctoral Fellow, Stanford University, 1990-93
- 1997, Senior Class Award for Teaching Excellence in Biology1998-2003, National Science Foundation CAREER Award1999, Department of Biology Teaching Excellence Recognition Award2001, Indiana University Trustees Teaching Award.2003-2007, Editor, Journal of Bacteriology2005, IBASM Academic Scientific Achievement Award2006, Top 2006 Stories in Science by The Future of Things2010, Fellow of the American Academy of Microbiology2012, Fellow of the American Association for the Advancement of Science
Our research interests and experimental approaches range widely. We work to answer questions about bacterial development and life history, including the mechanisms that underlie observed phenotypes, and the evolutionary forces that shape them:
- How do bacteria regulate the complex task of differentiation to create distinct cell types and morphologies?
- How do individual bacteria coordinate their adhesion to surfaces? What role does adhesion play in community ecology?
- Why do bacteria age, and what mechanisms drive the aging process?
As a model, we study the simple differentiating bacterium Caulobacter crescentus in which each cell division produces a motile swarmer cell and a stalked cell. In addition to differences in morphology, the two progeny cells have different fates. Only the stalked cell is competent to replicate DNA and divide. We increasingly study non-model bacterial species related to Caulobacter in order to bring an evolutionary perspective to our studies.
Caulobacter is easy to grow, has excellent genetics and a sequenced genome, and is ideally suited for cell biological approaches. We use a multitude of approaches that include mathematical modeling, biophysics, biochemistry, molecular biology, cell biology, microscopy, genetics, genomics, and proteomics. Our wide range of expertise and excellent collaborators allow us to focus on biological questions rather than specific methods and provides an outstanding multidisciplinary environment.
Regulation of cell differentiation. The different stages of polar development in Caulobacter are tightly coordinated with the cell cycle. We study transcriptional and proteolytic regulatory mechanisms and regulators that control the timed and ordered progression of these stages. We also study a checkpoint that couples polar development with cell division.
Control of cellular asymmetry. Before they divide, Caulobacter cells are asymmetric with a flagellum at one pole and a stalk and adhesive holdfast at the other pole. We have used genetic and molecular methods to identify genes that are involved in the maintenance of cellular asymmetry and we are studying their mechanism of action. We also have a strong interest in the mechanisms that target proteins and structures to a specific pole of the cell
Bacterial adhesion and biofilm formation. Adhesion is an important component of bacterial infections and is the first step of biofilm formation. In Caulobacter, adhesion is mediated by the holdfast, a complex polysaccharide with strong adhesive properties found at the tip of the stalk. We study the mechanism and regulation of single cell attachment to surfaces, holdfast synthesis, and the subsequent events that lead to the formation of biofilms.
Evolutionary genomics. We are taking advantage of next generation sequencing methods to sequence the genome of bacteria closely related to Caulobacter to investigate the evolution of cell shape and differentiation and the regulatory networks that control them. Towards this goal, we are isolating bacteria related to Caulobacter from a variety of environments using a phylogeny based screen to avoid the bias due to isolations based on phenotype.
Bacterial aging. Recent work has shown that organisms previously thought to be immortal, such as bacteria, demonstrate age-specific declines in reproduction. Asymmetry is thought to be important for aging by allowing the preferential segregation of damaged molecules to mother cells. We are using the asymmetrically dividing Caulobacter and close relatives that divide by the even more asymmetric mechanism of budding such as Hyphomonas to address the mechanism of aging and the role of asymmetry in this process.
- Li, G., Brown, P.B., J.X. Tang, Zhu, J., Quardokus, E.M., Fuqua, C., and Y.V. Brun. 2012. Surface contact stimulates the just-in-time deployment of bacterial adhesins. Molecular Microbiology, 83:41-51. [MicroCommentary] [Press release] [NIH Biomedical Beat feature] [article]
- Brown, P.J.B., M.A. de Pedro, D.T. Kysela, C. Van der Henst, J. Kim, X. De Bolle, C. Fuqua, and Y.V. Brun. 2012. Polar growth in the Alphaproteobacterial Order Rhizobiales. PNAS, 190: 1697-1701. [Press release] [Science Editor's Choice highlight] [article]
H.V. Hughes, C. Jiang, and Y.V. Brun. 2012. Quick guide: Caulobacter crescentus. Current Biology. 22: R507-509. [article]
- Kuru, E., H.V. Hughes, P.J.B. Brown, E. Hall, S. Tekkam, F. Cava, M.A. de Pedro, Y.V. Brun, and M.S. VanNieuwenhze. 2012. In situ Probing of Newly Synthesized Peptidoglycan in Live Bacteria with Fluorescent D-Amino Acids. Angewandte Chemie, DOI: 10.1002/anie.201206749. [Press release][Chemical and Engineering News feature][NIH Biomedical Beat Feature][Nature Reviews Microbiology feature][Nature Chemistry feature][NPR A Moment of Science] [article]
- Patel, K.B., E. Toh, X.B. Fernandez, A. Hanuszkiewicz, G.G. Hardy, Y.V. Brun, M. Bernards, and M.A. Valvano. 2012. Characterization of UDP-Glucose:Undecaprenyl-Phosphate Glucose-1-Phosphate Transferases of Escherichia coli and Caulobacter crescentus. Journal of Bacteriology, 194: 2646-57. [article]
- Madren, S.M., M.D. Hoffman, P.J.B. Brown, D.T. Kysela, Y.V. Brun and S.C. Jacobson. 2012. Microfluidic device for automated synchronization of bacterial cells. Analytical Chemistry, DOI: 10.1021/ac301565g. [Chemical & Engineering News feature] [article]
- Pejaver, V.R., J. An, S. Rhee, A. Bhan, J.-H. Choi, B. Liu, H. Lee, P.J.B. Brown, D. Kysela, Y.V. Brun, and S. Kim. 2012. GeneclusterViz: a tool for conserved gene cluster visualization, exploration and analysis. Bioinformatics Application Note, 28(11):1527-9. [article]
- Curtis, P.D., Quardokus, E.M., Lawler, M.L., Guo, X., Klein, D., Chen, J.C., Arnold, R.J., and Y.V. Brun. The scaffolding and signaling functions of a localization factor impact polar development. 2012. Molecular Microbiology, 84: 712-735. [article]
- Schlimpert, S., E. Klein, A. Briegel, H.V. Hughes, J. Kahnt, K. Bolte, U.G. Maier, Y.V. Brun, G.J. Jensen, Z. Gitai, and M. Thanbichler. Compartmentalization of a bacterial cell by protein diffusion barriers. 2012. Cell, 151: 1159-1160. [Cell Leading Edge Preview][Nature Reviews Microbiology feature] [article]
- Brown, P.J.B., D. Kysela, and Y.V. Brun. 2011. Polarity and the diversity of growth mechanisms in bacteria. Seminars in Cell and Developmental Biology. 22: 790-798. doi:10.1016/j.semcdb.2011.06.006. [abstract] [article]
- Li, G., J. Bensson, L. Nisimova, D. Munger , P. Mahautmr, and J. X. Tang, M.R. Maxey, and Y.V. Brun. 2011. Accumulation of swimming bacteria near a solid surface. Physical Review E, 84, 041932 [article]
- Chertkov, O., P.J.B. Brown, D.T. Kysela, 18 authors, H.-P. Klenk, Y.V. Brun. 2012. Complete genome sequence of Hirschia baltica type strain (IFAM 1418T). Standards in Genomic Sciences, 5:287-297. [article]
- Brown, P.J.B., D. Kysela, A. Buechlein, C. Hemmerich, and Y.V. Brun. 2011. Genome sequences of eight morphologically diverse Alphaproteobacteria. Journal of bacteriology, 193: 4567-8. [article]
- Hardy, G., R. Allen, E. Toh, M. Long, P.J.B. Brown, J. Cole-Tobian, and Y. V. Brun. 2010. A localized multimeric anchor attaches the Caulobacter holdfast to the cell pole. Molecular Microbiology, 76: 409-427. [abstract]
- Curtis, P.D. and Y.V. Brun. 2010. Getting in the loop: regulation of development in Caulobacter crescentus. Microbiology and Molecular Biology Reviews, 74: 13-41. [abstract]
- Berne, C., Kysela, D.T., and Y.V. Brun. 2010. A bacterial extracellular DNA inhibits settling of motile progeny cells within a biofilm. Molecular Microbiology, 76: 409-427. [abstract][commentary][press release][communiqué de presse]
- Hughes, V., E., Huitema, S., Pritchard, K.C., Keiler, Y.V., Brun, and P. Viollier. 2010. Protein localization and dynamics within a bacterial organelle. PNAS, 107:5599-604. [abstract]
- Curtis, P.D. and Y.V. Brun. 2010. A Novel Effector Protein Modulates Response Regulator Activity without Altering Phosphorylation. Molecular Cell, 39: 319-320. [abstract]
- Li, Z., M. Trimble, Y.V. Brun, and G. Jensen. 2007. Direct in situ Visualization of FtsZ Filaments in Caulobacter crescentus by Electron Cryotomography. The EMBO Journal, 26, 4694-4708. [abstract]
- Wagner, J.K., S. Setayeshgar, L. Sharon, J. Reilly, and Y.V. Brun. 2006. A nutrient uptake role for bacterial cell envelope extensions. PNAS, 103: 11772-11777. [abstract][Press release][Commentary]
- Tsang, P., G. Li, Y.V. Brun, B. Freund, and J. X. Tang. 2006. Adhesion of single bacterial cells in the micronewton range. PNAS, 103: 5764-68. [abstract][Press release]