Judy D. Wall, PhD



Curators Distinguished Professor Emerita



BA Chemistry University of North Carolina Greensboro, N.C.
PhD Biochemistry Duke University Durham, N.C.

Research Areas

Environmental microbiology; bioremediation of toxic metal; genetics and biochemistry of sulfate-reducing bacteria.

Research Description

Have you ever come across a stagnant pool that smelled like rotten eggs when you disturbed it? Or, have you wondered why iron pipes corrode in soil? Both the smell and the corrosion are caused by the sulfate-reducing bacteria that derive energy not from oxygen, but from sulfate, which is reduced to hydrogen sulfide. Do these bacteria only cause problems? Probably not, because we believe they can assist bioremediation, the destruction of toxic contaminants in the environment. Since oxygen kills these bacteria, all work with them must be carried out in the absence of air. Obviously, none but the most committed (stubborn) would work with them.

We are investigating the genetics and metabolism of hydrogen, iron, and sulfate in these bacteria. Just how do they make energy and is hydrogen an important intermediate in their metabolism as well as a substrate? How do they corrode iron? Metallic iron can serve as reductant and the Fe2+ produced is water soluble, until it is irrevocably precipitated by the sulfide ions also produced by the bacteria. Are the bacteria caught in a vicious cycle of removing iron that they need for growth, by the sulfide that is produced during growth? Do they need an iron acquisition system to grow?

The laboratory is also looking at metabolism of toxic metals by these bacteria that may contribute to the bioremediation of contaminated soils and groundwater. These bacteria convert a soluble form of uranium to an insoluble form that precipitates from water. Can we understand how this occurs? Can we increase the rate that this happens? Is the insoluble form used or is it inert forever? Many questions drive the research. Our studies abound with Southerns, cloning, PCRs, transposons, and problems. What we need now is a little intelligent help in understanding these fascinating and challenging organisms.

Notable Honors and Awards

  • Awarded Emerita status by Biochemistry Faculty, 2018
  • Southeastern Conference Faculty Achievement Award Winner, 2014
  • Curators’ Distinguished Professor, University of Missouri System, 2013
  • Fellow, American Academy for the Advancement of Science
  • Fellow, American Academy of Microbiology
  • Board of Governors, American Academy of Microbiology
  • Editor-in-Chief, Applied and Environmental Microbiology, 1995-01
  • American Society for Microbiology Chair/Elect & Chair Division K 1990-92
  • Editorial Boards
    • Environmental Microbiology (2005-18)
    • Journal of Bacteriology (1988-96; 2007-15)
    • Applied and Environmental Microbiology (1992-93; 2001-21; Editor 1993-95; Editor-in-Chief 1995-2001)
    • Annual Review of Microbiology (1997-2001)
  • Advisory Boards
    • DOE Biological and Environmental Research Advisory Committee (2008-2017)
    • NSF Center for Dark Energy Biosphere Investigations External Advisory Board (2016-2019)
    • DOE Systems Biology Knowledgebase, KBase (2012-2020)
    • PNNL Environmental Molecular Sciences Laboratory Advisory Committee (2017-2020)
    • LBNL Ecosystems and Networks Integrated with Genes and Molecular Assemblies (ENIGMA) Science Advisory Board (2019-)
  • Conference organization
    • Member Working Group for EU-US Environmental Biotechnology Taskforce, 1994-present
    • Chair, DOE BERAC Expert Committee on Low Dose Radiation Research Evaluation, 2015-16
    • Co-Organizer, DOE Molecular Science Challenges Workshop, May 27-28, 2014
    • Co-Organizer, Sulfate-Reducing Bacteria Genome Sequencing Jamboree, 2003
    • Gordon Research Conference on Applied and Environmental Microbiology, Co-Chair, 2001; Chair, 2003
    • Organizing Committee, International Symposium on Photosynthetic Prokaryotes, 1988-94
    • Organizer, 6th Annual Conference for the Molecular Biology Conference, Molecular Biology of Photosynthetic Prokaryotes, 1980

Selected Publications

Day LA, De León KB, Kempher ML, Zhou J, Wall JD. (2019). Complete Genome Sequence of Desulfovibrio desulfuricans IC1, a Sulfonate-Respiring Anaerobe. Microbiol Resour Announc. 8(31). doi: 10.1128/MRA.00456-19. [PubMed]

Christensen GA, Gionfriddo CM, King AJ, Moberly JG, Miller CL, Somenahally AC, Callister SJ, Brewer H, Podar M, Brown SD, Palumbo AV, Brandt CC, Wymore AM, Brooks SC, Hwang C, Fields MW, Wall JD, Gilmour CC, Elias DA. (2019). Determining the Reliability of Measuring Mercury Cycling Gene Abundance with Correlations with Mercury and Methylmercury Concentrations. Environ Sci Technol. 53(15):8649-8663. doi: 10.1021/acs.est.8b06389. [PubMed]

Date SS, Parks JM, Rush KW, Wall JD, Ragsdale SW, Johs A. (2019). Kinetics of Enzymatic Mercury Methylation at Nanomolar Concentrations Catalyzed by HgcAB. Appl Environ Microbiol. 85(13). doi: 10.1128/AEM.00438-19. Print 2019 Jul 1. [PubMed]

Rajeev L, Luning EG, Zane GM, Juba TR, Kazakov AE, Novichkov PS, Wall JD, Mukhopadhyay A. (2019). LurR is a regulator of the central lactate oxidation pathway in sulfate-reducing Desulfovibrio species. PLoS One. 14(4):e0214960. doi: 10.1371/journal.pone.0214960. eCollection 2019. [PubMed]

Bertran E, Leavitt WD, Pellerin A, Zane GM, Wall JD, Halevy I, Wing BA, Johnston DT. (2018). Deconstructing the Dissimilatory Sulfate Reduction Pathway: Isotope Fractionation of a Mutant Unable of Growth on Sulfate. Front Microbiol. 9:3110. doi: 10.3389/fmicb.2018.03110. eCollection 2018. [PubMed]

Rajeev L, Garber ME, Zane GM, Price MN, Dubchak I, Wall JD, Novichkov PS, Mukhopadhyay A, Kazakov AE. (2019). A new family of transcriptional regulators of tungstoenzymes and molybdate/tungstate transport. Environ Microbiol. 21(2):784-799. doi: 10.1111/1462-2920.14500. [PubMed]

Ge X, Vaccaro BJ, Thorgersen MP, Poole FL 2nd, Majumder EL, Zane GM, De León KB, Lancaster WA, Moon JW, Paradis CJ, von Netzer F, Stahl DA, Adams PD, Arkin AP, Wall JD, Hazen TC, Adams MWW. (2019). Iron- and aluminium-induced depletion of molybdenum in acidic environments impedes the nitrogen cycle. Environ Microbiol. 21(1):152-163. doi: 10.1111/1462-2920.14435. [PubMed]

Price MN, Wetmore KM, Waters RJ, Callaghan M, Ray J, Liu H, Kuehl JV, Melnyk RA, Lamson JS, Suh Y, Carlson HK, Esquivel Z, Sadeeshkumar H, Chakraborty R, Zane GM, Rubin BE, Wall JD, Visel A, Bristow J, Blow MJ, Arkin AP, Deutschbauer AM. (2018). Mutant phenotypes for thousands of bacterial genes of unknown function. Nature. 557(7706):503-509. doi: 10.1038/s41586-018-0124-0. [PubMed]

Zhang C, Parrello D, Brown PJB, Wall JD, Hu Z. (2018). A novel whole-cell biosensor of Pseudomonas aeruginosa to monitor the expression of quorum sensing genes. Appl Microbiol Biotechnol. 102(14):6023-6038. doi: 10.1007/s00253-018-9044-z. [PubMed]

Franco LC, Steinbeisser S, Zane GM, Wall JD, Fields MW. (2018). Cr(VI) reduction and physiological toxicity are impacted by resource ratio in Desulfovibrio vulgaris. Appl Microbiol Biotechnol. 102(6):2839-2850. doi: 10.1007/s00253-017-8724-4. [PubMed]

Price MN, Zane GM, Kuehl JV, Melnyk RA, Wall JD, Deutschbauer AM, Arkin AP. (2018). Filling gaps in bacterial amino acid biosynthesis pathways with high-throughput genetics. PLoS Genet. 14(1):e1007147. doi: 10.1371/journal.pgen.1007147. eCollection 2018 Jan. Erratum in: PLoS Genet. 2019 Apr 3;15(4):e1008106. [PubMed]

Christensen GA, Somenahally AC, Moberly JG, Miller CM, King AJ, Gilmour CC, Brown SD, Podar M, Brandt CC, Brooks SC, Palumbo AV, Wall JD, Elias DA. (2018). Carbon Amendments Alter Microbial Community Structure and Net Mercury Methylation Potential in Sediments. Appl Environ Microbiol. 84(3). doi: 10.1128/AEM.01049-17. Print 2018 Feb 1. [PubMed]