James A. Imlay

About

James A. Imlay is the Maybelle Leland Swanlund Endowed Chair and Associate Head of the Department of Microbiology at the University of Illinois. He holds a B.S. in Chemistry and English from Duke University (1981), a Ph.D. in Biochemistry from the University of California, Berkeley (1987), and completed postdoctoral work in Biochemistry at Duke University (1987-1992). His research focuses on the molecular mechanisms of oxidative damage and the cellular defenses against oxidants, with a particular emphasis on microbial physiology and enzymology. Imlay's laboratory investigates fundamental questions about the toxicity of reactive oxygen species such as superoxide (O2-) and hydrogen peroxide (H2O2), how these species arise within cells, the biomolecular damage they cause, and the strategies cells employ to avoid or repair this damage. His work primarily uses Escherichia coli as a model organism, given its well-understood metabolism, but the findings have broader implications for other bacteria and higher organisms. Imlay's research has elucidated how flavoenzymes inadvertently generate reactive oxygen species during aerobic metabolism, identified the specific enzyme targets of superoxide and hydrogen peroxide, and detailed the cellular repair and defense mechanisms, including enzyme repair, metal cofactor replacement, and iron sequestration. Additionally, his studies extend to understanding why obligate anaerobes cannot grow in the presence of oxygen and how phagocytes kill…

Research topics

• Chemistry
• Biology
• Biochemistry
• Cell biology
• Genetics
• Microbiology
• Engineering
• Ecology
• Biochemical engineering
• Physiology

Selected publications

• When anaerobes encounter oxygen: mechanisms of oxygen toxicity, tolerance and defence

  Nature Reviews Microbiology · 2021 · 299 citations

  Senior authorCorresponding
  PublisherOA PDFDOI

• Where in the world do bacteria experience oxidative stress?

  Environmental Microbiology · 2018-10-11 · 296 citations

  reviewOpen access1st authorCorresponding

  Summary Reactive oxygen species – superoxide, hydrogen peroxide and hydroxyl radicals – have long been suspected of constraining bacterial growth in important microbial habitats and indeed of shaping microbial communities. Over recent decades, studies of paradigmatic organisms such as Escherichia coli , Salmonella typhimurium , Bacillus subtilis and Saccharomyces cerevisiae have pinpointed the biomolecules that oxidants can damage and the strategies by which microbes minimize their injuries. Wha…

  PublisherOA PDFDOI

• How Microbes Defend Themselves From Incoming Hydrogen Peroxide

  Frontiers in Immunology · 2021 · 140 citations

  Senior authorCorresponding

  -mediated damage. However, individual organisms have tailored these transcription factors and their regulons to suit their particular environmental niches. Some bacteria even contain both OxyR and PerR, raising the question as to why they need both systems. In lab experiments these regulators can also respond to nitric oxide and disulfide stress, although it is unclear whether the responses are physiologically relevant. The next step is to extend these studies to natural environments, so that we…

  PublisherOA PDFDOI

• How Microbes Evolved to Tolerate Oxygen

  Trends in Microbiology · 2020 · 110 citations

  Senior authorCorresponding
  PublisherOA PDFDOI

• Cystine import is a valuable but risky process whose hazards <i>Escherichia coli</i> minimizes by inducing a cysteine exporter

  Molecular Microbiology · 2019-10-15 · 59 citations

  articleOpen accessSenior authorCorresponding

  The structure of free cysteine makes it vulnerable to oxidation by molecular oxygen; consequently, organisms that live in oxic habitats have acquired the ability to import cystine as a sulfur source. We show that cystine imported into Escherichia coli can transfer disulfide bonds to cytoplasmic proteins. To minimize this problem, the imported cystine is rapidly reduced. However, this conversion of cystine to cysteine precludes product inhibition of the importer, so cystine import continues into…

  PublisherOA PDFDOI

Recent grants

• The Physiology of Oxidative Stress in Escherichia coli

  NIH · $7.9M · 1994–2025

• Oxidative stress and the cellular thiol status of Escherichia coli

  NIH · $2.2M · 2012–2021

• The Physiology of Oxidative Stress in Escherichia coli

  NIH · $5.3M · 1994–2017

Frequent coauthors

• Irwin Fridovich

  Duke University Hospital

  26 shared

• Sergey Korshunov

  University of Illinois Urbana-Champaign

  8 shared

• Stefanos Giannakis

  Universidad Politécnica de Madrid

  8 shared

• Karin R. Chonoles Imlay

  University of Illinois Urbana-Champaign

  7 shared

• Sanjay Kumar Rohaun

  University of Illinois Urbana-Champaign

  6 shared

• Sethu Ramakrishnan

  University of Illinois Urbana-Champaign

  6 shared

• Anshika Gupta

  Ministry of Health and Family Welfare

  6 shared

• Stuart Linn

  University of California, Berkeley

  6 shared

Labs

• Imlay LabPI

  University of Illinois at Urbana-Champaign

Awards & honors

• Maybelle Leland Swanlund Endowed Chair, Microbiology

Similar researchers at University of Illinois Urbana-Champaign

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• Gary J. Olsenh-58
• Cari Vanderpoolh-35