"Enzyme Identified as Key Factor in the Yellow Coloration of Urine"

Scientists at the University of Maryland and the National Institutes of Health have identified bilirubin reductase, an enzyme produced by gut microbes, as the key factor in converting bilirubin into urobilin, which gives urine its yellow color. This discovery, published in Nature Microbiology, not only solves a longstanding biological question but also has significant implications for understanding the gut microbiome's influence on conditions like jaundice and inflammatory bowel disease. The presence or absence of bilirubin reductase in individuals could impact health conditions related to bilirubin levels, offering new insights into the gut-liver axis and the overall role of the gut microbiome in human health.