Stabilizing the enzyme in fish odor syndrome
Fish odor syndrome, or trimethylaminuria, is a disease in which the liver cannot break down the smelly chemical trimethylamine, or TMA, that is produced by enzymes from bacteria residing in the gut. There is no cure for fish odor syndrome, which gives people an unpleasant fishy smell that can affect breath, sweat, urine and vaginal fluids.
Our research team at the University of Warwick is working to prevent the syndrome through studying the enzyme in the gut that produces trimethylamine.
Fish odor syndrome starts when an enzyme pathway in the gut called CntA/B produces TMA. The enzyme breaks down a TMA precursor called L-carnitine, which is found in dairy, fish and meat. If an individual lacks a functional liver enzyme called FMO3, they cannot degrade TMA into a non-smelly chemical form, trimethylamine oxide, or TMAO. The TMA then builds up in the body and ends up in bodily fluids.
In a recent paper, published in the Journal of Biological Chemistry, our team in Yin Chen's lab at Warwick's School of Life Sciences focused on the CntA protein of the CntA/B enzyme, to stabilize and study it.
CntA/B is a notoriously hard enzyme to study, but once it was stabilized, we were able to gain insight into how CntA perceives its L-carnitine substrate with a 3D crystal structure model, and by studying the complete electron transfer pathway, we could see how the protein is able to turn over TMA.
Now that we understand how exactly TMA is produced in the gut and that the enzyme can be inhibited, there are grounds for further research into future discovery of drugs targeting the TMA-producing enzyme in the human gut.
We have identified novel, drug-like inhibitors that can inhibit CntA function and thus TMA formation with the potential to attenuate TMA formation in the gut microbiome. This is vital not only for people who have fish odor syndrome, but also because TMA can accelerate atherosclerosis and heart disease.
This article was adapted from a University of Warwick press release. Read the original here.
Enjoy reading ASBMB Today?
Become a member to receive the print edition four times a year and the digital edition monthly.
Learn moreGet the latest from ASBMB Today
Enter your email address, and we’ll send you a weekly email with recent articles, interviews and more.
Latest in Science
Science highlights or most popular articles

Cholesterol regulatory genes predict liver transplant outcomes
Researchers identify a link between cholesterol-regulating genes and liver transplant success, which could improve donor screening and patient outcomes.

Lipid signatures for a rare neurological disorder
Researchers find distinct lipid patterns linked to a rare autoimmune neurological disorder, offering hope for effective targeted therapies for patients.

Disease-linked mutations disrupt protein phase behavior
Researchers find that pathogenic missense mutations are enriched threefold in phrase-separating intrinsically disordered regions of proteins.

The dual role of asprosin in chronic fatty liver disease
Researchers uncover a hormone called asprosin that may serve as a potential biomarker for the diagnosis of chronic fatty liver disease and monitoring disease progression.

Novel inhibitor targets RAS-driven cancers
Researchers in Louisville identify a small-molecule drug that blocks RALGEF signaling downstream of mutant RAS. The compound suppresses tumor growth with low toxicity, revealing a new therapeutic strategy for RAS-driven malignancies.

Catching tau in the act
Using a new proximity-labeling approach, researchers reveal how tangles of the brain-associated protein tau may disrupt RNA biology long before neurons die.