Valley Stewart

image of Valley Stewart



Microbiology and Molecular Genetics

Offices and Labs

239A Briggs Hall
(530) 754-7994


1982 PhD Microbiology University of Virginia
1977 BA Biology University of Colorado

Research Interests

Signaling in bacterium-plant interactions

I currently am a sabbatical leave visitor in the laboratory of Prof. Pamela Ronald (UC Davis), who studies the control of innate immune response by rice (Oryzae sativa) to Xanthomonas oryzae.  This bacterium causes economically significant diseases in an agricultural staple that also is a model for broadly understanding cereal genetics.  Our goal is to integrate analyses of both pathogen and host as we seek to understand plant resistance.

Completed Research Projects

Physiology and regulation of anaerobic resipiration in Escherichia coli (supported by NIGMS)

Phosphatase mechanism and function in two-component signal transduction (supported by NIGMS)

Nitrogen assimilation by Klebsiella oxytoca (supported by DOE)

Hyper-encapsulation by invasive Klebsiella pneumoniae (supported by NIAID)

Regulation of denitrification in Pseudomonas aeruginosa (supported by NIAID)


MIC 102 Introductory Microbiology
MIC 111 Human Microbiology
MIC 150 Genomes of Pathogenic Bacteria

Personal Interests

UC Davis Concert Band
UC Davis Symphony Orchestra


9/25/2015 8:22:16 AM
  • Boudes, M., N. Lazar, M. Graille, D. Durand, T. A. Gaidenko, V. Stewart, and H. van Tilbeurgh.  2012.  The structure of the NasR transcription antiterminator reveals a one-component system with a NIT nitrate receptor coupled to an ANTAR RNA-binding effector.  Mol. Microbiol. 85: 431-444.  PMID: 22690729

  • Huynh, T. N., C. E. Noriega, and V. Stewart.  2013.  Missense substitutions reflecting regulatory control of transmitter phosphatase activity in two-component signaling.  Mol. Microbiol. 88:459-472.  PMCID: PMC3633741

  • Huynh, T. N., L.-L. Chen, and V. Stewart.  2015.  Sensor–response regulator interactions in a cross-regulated signal transduction network.  Microbiology 161:1504-1515.  PMID: 25873583

  • Huynh, T. N., H.-Y. Lin, C. E. Noriega, A. V. Lin, and V. Stewart.  2015.  Crosstalk Inhibition Nullified by a Receiver Domain Missense Substitution.  J. Bacteriol. 197: 3294-3306.  PMID: 26260457