Discovery and Characterization of Gut Microbiota Decarboxylases That Can Produce the Neurotransmitter Tryptamine

Overview

Journal Cell Host Microbe

Publisher Cell Press

Specialties Infectious Diseases
Microbiology

Date 2014 Sep 30

PMID 25263219

Citations 318

Authors

Brianna B Williams

Andrew H Van Benschoten

Peter Cimermancic

Mohamed S Donia

Michael Zimmermann

Mao Taketani

Atsushi Ishihara

Purna C Kashyap

James S Fraser

Michael A Fischbach

Affiliations

Soon will be listed here.

Abstract

Several recent studies describe the influence of the gut microbiota on host brain and behavior. However, the mechanisms responsible for microbiota-nervous system interactions are largely unknown. Using a combination of genetics, biochemistry, and crystallography, we identify and characterize two phylogenetically distinct enzymes found in the human microbiome that decarboxylate tryptophan to form the β-arylamine neurotransmitter tryptamine. Although this enzymatic activity is exceedingly rare among bacteria more broadly, analysis of the Human Microbiome Project data demonstrate that at least 10% of the human population harbors at least one bacterium encoding a tryptophan decarboxylase in their gut community. Our results uncover a previously unrecognized enzymatic activity that can give rise to host-modulatory compounds and suggests a potential direct mechanism by which gut microbiota can influence host physiology, including behavior.

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