John D. Helmann

John D. Helmann




Department of Microbiology
327 Wing Hall
Cornell University
Ithaca, NY 14853-2703


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Department Profile


John Helmann earned bachelor's degrees in Chemistry and Biology (University of California, Santa Cruz) in 1982. He then joined the Department of Biochemistry at the University of California at Berkeley where he studied bacterial RNA polymerase with Dr. Michael Chamberlin and earned a Ph.D. in 1987. From 1987 to 1990, Dr. Helmann worked as a post-doctoral fellow with Dr. Christopher T. Walsh at the Harvard Medical School. His post-doctoral research, on the regulation of bacterial mercuric ion resistance determinants, was supported by the Jane Coffin Childs Memorial Medical Research Foundation. Dr. Helmann joined the Section of Microbiology at Cornell as an Assistant Professor in 1990 and joined the graduate field of Biochemistry, Molecular, and Cell Biology in 1991. He was promoted to Associate Professor in 1996 and Professor in 2002.

Research Description

The difference between what an organism can do (genetic potential) and what it actually does (phenotype) is often regulated at the level of transcription. Our laboratory studies Bacillus subtilis, a Gram-positive soil bacterium and genetic model system. We are interested in the global patterns of transcriptional control and the mechanisms of the corresponding regulatory proteins and pathways. more


    T. Mascher, A. Hachmann, and J.D. Helmann. Regulatory Overlap and Functional Redundancy Among Bacillus subtilis Extracytoplasmic Function (ECF) Sigma-Factors. J Bacteriol. 2007 Aug 3; [Epub ahead of print]

    S. Soonsanga, M. Fuangthong, and J.D. Helmann Mutational analysis of active site residues essential for sensing of organic hydroperoxides by Bacillus subtilis OhrR. J Bacteriol. 2007 Jul 27; [Epub ahead of print]

    S. Jordan, E. Rietkotter, M.A. Strauch, F. Kalamorz, B.G. Butcher, J.D. Helmann and T. Mascher. 2007. LiaRS-dependent gene expression is embedded in transition state regulation in Bacillus subtilis. Microbiology. 153:2530-40.

    F. Hochgräfe, J. Mostertz, D.C. Pöther, D. Becher, J.D. Helmann JD, and M. Hecker. S-cysteinylation is a general mechanism for thiol protection of Bacillus subtilis proteins after oxidative stress.J Biol Chem. 2007 Jul 4; [Epub ahead of print]

    B.G. Butcher, T. Mascher, and J. D. Helmann. 2007. Environmental sensing and the role of extracytoplasmic function (ECF) sigma factors in Bacterial Physiology- A Molecular Approach, Walid M. El-Sharoud (Ed.). Springer-Verlag GmbH Berlin Heidelberg.

    J. D. Helmann, S. Soonsanga, and S. Gabriel. 2007. Metalloregulators: Arbiters of Metal Sufficiency, in How Bacteria Handle Heavy Metals (Microbiology Monographs). Dietrich H. Nies and Simon Silver (Eds.), Springer-Verlag GmbH Berlin Heidelberg.

    L. Salzberg and J.D. Helmann. 2007. An antibiotic-inducible cell-wall associated protein that protects Bacillus subtilis from autolysis. J. Bacteriol. 189:4671-80.

    J.W. Lee, S. Soonsanga, and J.D. Helmann. 2007. A complex thiolate switch regulates the Bacillus subtilis organic peroxide sensor OhrR. Proc. Natl. Acad. Sci USA . 104:8743-8.

    J.W. Lee and J.D. Helmann. 2007 Functional specialization within the Fur family of metalloregulators. Biometals. Jan 10; [Epub ahead of print]

    M. A. DeWitt, J. I. Kliegman, J.D. Helmann, R.G. Brennan, D.L. Farrens and A. Glasfeld. 2007. The Conformations of the Manganese Transport Regulator of Bacillus subtilis in its Metal-free State. J. Mol. Biol. 365:1257-1265.

    T. Mascher, J.D. Helmann, G. Under. 2006. Stimulus perception in bacterial signal-transducing histidine kinases. Microbiol Mol Biol Rev. 70:910-38.

    J.W. Lee and J.D. Helmann. 2006 Biochemical Characterization of the Structural Zn2+ Site in the Bacillus subtilis Peroxide Sensor PerR. J Biol Chem 281, 23567-23578.

    S. Jordan, A. Junker, J.D. Helmann, and T. Mascher. 2006. Regulation of LiaRS-Dependent Gene Expression in Bacillus subtilis: Identification of Inhibitor Proteins, Regulator Binding Sites, and Target Gene of a Conserved Cell Envelope Stress-Sensing Two Component System. J. Bacteriol. 188:5153-5166.

    J. Ollinger, K.-B. Song, H. Antelmann, M. Hecker, and J.D. Helmann. 2006. Role of the Fur Regulon in Iron Transport in Bacillus subtilis. J. Bacteriol. 188: 3664-3673.

    B. Butcher and J.D. Helmann. 2006. Identification of Bacillus subtilis  σW-dependent genes that provide intrinsic resistance to antimicrobial compounds produced by Bacilli.  Mol. Microbiol. 60:765-782.

    J.I.  Kliegman, S.L. Griner, J.D. Helmann, R.G. Brennan and A. Glasfeld. 2006. The Structural Basis for the Metal Selective Activation of the Manganese Transport Regulator of Bacillus subtilis.  Biochemistry  45:3493-3505.

    J.-W. Lee and J.D. Helmann. 2006. The PerR transcription factor senses H2O2 by metal catalysed histidine oxidation. Nature 440:363-367.

    P.S. Choi, Z. Naal, C. Moore, E. Casado-Rivera, H.D. Abruña, J.D. Helmann, J.P. Shapleigh. 2006. Assessing the impact of nitric oxide produced by denitrifiers on other bacteria. Applied and Env. Microbiol. 72:2200-2205.

    Click here for Dr. Helmann's PubMed listings.