Professor Dr Andreas J. Bäumler
- Section Microbiology and Immunology
- Location Davis, CA, United States
- Election year 2020
Research
Research Priorities: Enteric pathogens, the host and its Microbiota
Andreas J. Bäumler is a microbiologist and immunologist. He pioneered studies on the physiology of enteric pathogens in the natural context of a host-associated microbial community. This work identified epithelial energy metabolism as host control mechanism critical for maintaining homeostasis. Gut dysbiosis resulting from disruption of this host control mechanism underlies a broad range of non-communicable diseases.
An imbalance in the colonic microbiota might underlie many human diseases, but the mechanisms maintaining homeostasis remain elusive. Bäumler’s work has established the concept that the metabolism of the colonic epithelium functions as a control switch, mediating a shift between homeostatic and dysbiotic communities. During homeostasis, colonic epithelial metabolism is directed towards oxidative phosphorylation, resulting in high epithelial oxygen consumption. The consequent epithelial hypoxia helps maintain a microbial community dominated by obligate anaerobic bacteria, which provide benefit by converting fiber into fermentation products absorbed by the host.
Bäumler’s work shows that conditions that alter the metabolism of the colonic epithelium increase epithelial oxygenation, thereby driving an expansion of facultative anaerobic Enterobacteriaceae, a hallmark of dysbiosis in the colon. This dysbiotic shift in the gut microbiota is observed during infection with enteric pathogens, such as Salmonella or Citrobacter, which subvert epithelial metabolism to escape niche protection conferred by the gut microbiota. However, this mechanism also underlies a dysbiotic expansion of Enterobacteriaceae, such as Escherichia coli, in models of inflammatory bowel disease, colorectal cancer or after antibiotic treatment.
Notably, Bäumler’s work shows that an increased availability of respiratory electron acceptors is a shared driver of gut dysbiosis in each of these settings. By providing a mechanistic explanation for gut homeostasis, his brand of reductionist microbiota research provides a novel lynchpin for strategies to remediate dysbiosis in a broad spectrum of human diseases by harnessing host control mechanisms to restore epithelial hypoxia for therapeutic means.
Andreas J. Bäumler is a microbiologist and immunologist. He pioneered studies on the physiology of enteric pathogens in the natural context of a host-associated microbial community. This work identified epithelial energy metabolism as host control mechanism critical for maintaining homeostasis. Gut dysbiosis resulting from disruption of this host control mechanism underlies a broad range of non-communicable diseases.
An imbalance in the colonic microbiota might underlie many human diseases, but the mechanisms maintaining homeostasis remain elusive. Bäumler’s work has established the concept that the metabolism of the colonic epithelium functions as a control switch, mediating a shift between homeostatic and dysbiotic communities. During homeostasis, colonic epithelial metabolism is directed towards oxidative phosphorylation, resulting in high epithelial oxygen consumption. The consequent epithelial hypoxia helps maintain a microbial community dominated by obligate anaerobic bacteria, which provide benefit by converting fiber into fermentation products absorbed by the host.
Bäumler’s work shows that conditions that alter the metabolism of the colonic epithelium increase epithelial oxygenation, thereby driving an expansion of facultative anaerobic Enterobacteriaceae, a hallmark of dysbiosis in the colon. This dysbiotic shift in the gut microbiota is observed during infection with enteric pathogens, such as Salmonella or Citrobacter, which subvert epithelial metabolism to escape niche protection conferred by the gut microbiota. However, this mechanism also underlies a dysbiotic expansion of Enterobacteriaceae, such as Escherichia coli, in models of inflammatory bowel disease, colorectal cancer or after antibiotic treatment.
Notably, Bäumler’s work shows that an increased availability of respiratory electron acceptors is a shared driver of gut dysbiosis in each of these settings. By providing a mechanistic explanation for gut homeostasis, his brand of reductionist microbiota research provides a novel lynchpin for strategies to remediate dysbiosis in a broad spectrum of human diseases by harnessing host control mechanisms to restore epithelial hypoxia for therapeutic means.
Career
- since 2005 Professor of Medical Microbiology and Immunology, University of California, Davis, USA
- 2001-2005 Associate Professor of Medical Microbiology and Immunology, Texas A&M University Health Science Center, College Station, USA
- 1996-2001 Assistant Professor of Medical Microbiology and Immunology, Texas A&M University Health Science Center, College Station, USA
- 1995-1996 Research Assistant Professor of Molecular Microbiology and Immunology, Oregon Health & Science University, Portland, USA
- 1992-1995 Postdoctoral fellow, Department of Molecular Microbiology and Immunology, Oregon Health & Science University, Portland, USA
- 1989-1992 Doctor of Natural Sciences, Department of Microbiology II, Eberhard Karls University of Tübingen, Germany
Functions
- since 2017 Editor in Chief of Infection and Immunity
- since 2007 Vice Chair of Research, Department of Medical Microbiology and Immunology, University of California, Davis, USA
Honours and Memberships
- since 2023 Member, National Academy of Sciences, USA
- 2021 Robert Koch Award, Robert-Koch-Stiftung
- since 2020 Member of the German National Academy of Sciences Leopoldina
- since 2010 Fellow of the American Academy of Microbiology