Edward G. Ruby, Ph.D. Professor, Medical Microbiology and Immunology Room 5203 Microbial Sciences Building 1550 Linden Drive Madison, WI 53706-1521 Office: (608) 262-5911 Lab: (608) 262-5550 Fax: (608) 262-8418 egruby@wisc.edu

Research Interests

One of the long-term objectives of our research is to define the bacterial basis for biochemical and molecular events that characterize colonization of animal epithelial tissue. To accomplish this goal we have chosen as a model system the symbiotic infection of the light organ of the squid Euprymna scolopes by the luminous bacterium Vibrio fischeri. This system provides a simple, experimentally accessible, paradigm for studying specific, beneficial, host-bacterial interactions. Our recent investigations have centered on the events characterizing the initiation, colonization, and persistence of the symbiotic infection in newly hatched juvenile squids using bacterial mutants to manipulate and assay the complex succession of signaling and responses through which the host and bacterium communicate. Our recent completion of the V. fischeri genome project, and the construction of gene microarrays, has opened a new chapter in these studies.

We believe that this natural biological system serves as a model of pathogenic vibrio infection and, perhaps, of the evolution of the virulence state in vibrios; that is, bacterial and host determinants that potentiate light organ symbiosis may reveal convergences with known vibrio virulence factors, and promote the discovery of as yet undescribed ones. This work will also aid our understanding of the mechanisms by which benign colonizations of mollusk tissue serve as a reservoir for human pathogenic Vibrio species.

Academic Positions

1996-2004 – Professor & Senior Researcher, PBRC, University of Hawaii
1982-1997 – Professor, Biological Sciences, Univ. Southern Calif.

Academic Training

Postdoctoral, Univ. Calif., Los Angeles
Postdoctoral, Woods Hole Oceanogr. Instit.
Postdoctoral, Harvard University
Ph.D., Univ. Calif., San Diego
B.Sc., Stetson University

Recent Publications – NCBI PubMed search for "E.G. Ruby"

Adin DM, Phillips NJ, Gibson BW, Apicella MA, Ruby EG, McFall-Ngai MJ, Hall DB, Stabb EV. 2007. Characterization of htrB and msbB mutants of the light organ symbiont Vibrio fischeri. Appl. Environ. Microbiol. 2007 Dec 7; [Epub ahead of print]

Antunes LC, Schaefer AL, Ferreira RB, Qin N, Stevens AM, Ruby EG, Greenberg EP. 2007. Transcriptome analysis of the Vibrio fischeri LuxR-LuxI regulon. J. Bacteriol. 189:8387-8391.

Hussa EA, O'Shea TM, Darnell CL, Ruby EG, Visick KL. 2007. Two-component response regulators of Vibrio fischeri: identification, mutagenesis, and characterization. J. Bacteriol. 189:5825-5838.

Nelson EJ, Tunsjø HS, Fidopiastis PM, Sørum H, Ruby EG. 2007. A novel lux operon in the cryptically bioluminescent fish pathogen Vibrio salmonicida is associated with virulence. Appl Environ Microbiol. 73:1825-1833.

Whistler CA, Koropatnick TA, Pollack A, McFall-Ngai MJ, Ruby EG. 2007. The GacA global regulator of Vibrio fischeri is required for normal host tissue responses that limit subsequent bacterial colonization. Cellul. Microbiol. 9:766-778.

Visick KL, Ruby EG. 2006. Vibrio fischeri and its host: it takes two to tango. Curr. Opin. Microbiol. 9:632-638.

Sycuro LK, Ruby EG, McFall-Ngai M. 2006. Confocal microscopy of the light organ crypts in juvenile Euprymna scolopes reveals their morphological complexity and dynamic function in symbiosis. J. Morphol. 267:555-568.

Lupp, C., E. G. Ruby. 2005. Vibrio fischeri Uses Two Quorum-Sensing Systems for the Regulation of Early and Late Colonization Factors. J. Bacteriol., 187(11):3620-3629.

Ruby, E.G., M. Urbanowski, J. Campbell, A. Dunn, M. Faini, R. Gunsalus, P. Lostroh, C. Lupp, J. McCann, D. Millikan, A. Schaefer, E. Stabb, A. Stevens, K. Visick, C. Whistler, and E.P. Greenberg. 2005. Complete genome sequence of Vibrio fischeri: a symbiotic bacterium with pathogenic congeners. PNAS USA, (102):3004-09.

Lupp, C., E. G. Ruby. 2004. Vibrio fischeri LuxS and AinS: Comparative Study of Two Signal Synthases. J. Bacteriol., 186(12):3873-81.

Millikan, D. S., E. G. Ruby. 2004. Vibrio fischeri Flagellin A Is Essential for Normal Motility and for Symbiotic Competence during Initial Squid Light Organ Colonization. J Bacteriol., 186(13):4315-25.

Whistler, C.A., and E.G. Ruby. 2003. GacA regulates symbiotic colonization traits of V. fischeri and facilitates a beneficial association with an animal host. J. Bacteriol. 185:7202-7212.

McCann, J., E.V. Stabb, D.S. Millikan, and E.G. Ruby. 2003. Population dynamics of Vibrio fischeri during infection of Euprymna scolopes. Appl. Environ. Microbiol. 69:5928-5934.

Lupp, C., M. Urbanowski, E.P. Greenberg, and E.G. Ruby. 2003. The Vibrio fischeri quorum-sensing systems ain and lux sequentially induce luminescence gene expression, and are important for persistence in the squid host. Mol. Microbiol. 50:319-331.

Millikan, D.S., and E.G. Ruby. 2003. FlrA, a s54-dependent transcriptional activator in Vibrio fischeri, is required for motility and symbiotic light organ colonization. J. Bacteriol. 185:3547-3557.

Miyamoto, C.M., P.V. Dunlap, E.G. Ruby, and E.A. Meighen. 2003. LuxO controls luxR expression in Vibrio harveyi: evidence for a common regulatory mechanism in Vibrio. Mol. Microbiol. 48:537-548.

Stabb, E.V., and E.G. Ruby. 2003. Contribution of pilA to competitive colonization of Euprymna scolopes by Vibrio fischeri. Appl. Environ. Microbiol. 69:820-826.

Stabb, E.V., and E.G. Ruby. 2002. New RP4-based plasmids for conjugation between Escherichia coli and members of the Vibrionaceae. Meth. Enzymol. 358:413-426.

Lupp, C., R.E.W. Hancock, and E.G. Ruby. 2002. The Vibrio fischeri sapABCDF locus is required for normal growth, both in culture and in symbiosis. Arch. Microbiol. 179:57-65.

Fidopiastis, P.M., C.M. Miyamoto, M.G. Jobling, E.A. Meighen, and E.G. Ruby. 2002. LitR, a new transcriptional activator in Vibrio fischeri, regulates luminescence and symbiotic light organ colonization. Mol. Microbiol. 45:131-143.

Millikan, D.S., and E.G. Ruby. 2002. An altered motility phenotype in Vibrio fischeri that correlates with a symbiotic colonization defect. Appl. Environ. Microbiol. 68:2519-2528.

Aeckersberg, F., C. Lupp, B. Feliciano and E.G. Ruby. 2001. The Vibrio fischeri outer membrane protein OmpU plays a role in normal symbiotic colonization. J. Bacteriol. 183:6590-6597.

Stabb, E.V., K.A. Reich, and E.G. Ruby. 2001 Vibrio fischeri genes hvnA and hvnB encode secreted NAD+-glycohydrolases. J. Bacteriol. 183:309-317.

Nyholm, S.V., E.V. Stabb, E.G. Ruby, and M.J. McFall-Ngai. 2000. Establishment of an animal-bacteria association: recruiting symbiotic vibrios from the environment. Proc. Natl. Acad. Sci. USA 97:10231-10235.

Visick, K.L., J. Foster, J. Doino, M.J. McFall-Ngai, and E.G. Ruby. 2000. Vibrio fischeri lux genes play an important role in colonization and development of the host light organ. J. Bacteriol. 182:4578-4586.

Graf, J., and E.G. Ruby. 2000. Novel effects of a transposon insertion in the Vibrio fischeri glnD gene: defects in iron uptake and symbiotic persistence in addition to nitrogen utilization. Mol. Microbiol. 37:168-179.

Fidopiastis, P.M., H. Sörom, and E.G. Ruby. 1999. Cryptic luminescence in the cold-water fish pathogen Vibrio salmonicida. Arch. Microbiol. 171:205-209.