For years, the specific reason behind the yellow color of urine remained a secret, puzzling researchers and physician alike. However, a recent development has lastly shed light on this everyday biological characteristic. A new research study found that an enzyme, called bilirubin reductase, is eventually accountable for giving urine its particular yellow color.
” Its remarkable that an everyday biological phenomenon went unexplained for so long, and our group is thrilled to be able to explain it,” said lead author Brantley Hall, an assistant professor at the University of Marylands Department of Cell Biology and Molecular Genetics.
Credit: DALL-E 3.
The journey from red to yellow
” Now that weve determined this enzyme, we can begin examining how the bacteria in our gut effect circulating bilirubin levels and related health conditions like jaundice,” said research study co-author and NIH Investigator Xiaofang Jiang. “This discovery lays the structure for understanding the gut-liver axis.”
This process yields bilirubin, an intense orange substance. Bilirubin then takes a trip to the gut, where gut bacteria change it into a colorless substance called urobilinogen.
Bilirubin then takes a trip to the gut, where gut bacteria transform it into a colorless compound called urobilinogen. Previous research studies had actually identified the conversion of bilirubin to urobilinogen but stopped working to determine the particular enzyme responsible. Clients with jaundice have a high build-up of bilirubin, whereas lower levels of urobilin have been observed in people with IBD.
A brand-new research study discovered that an enzyme, understood as bilirubin reductase, is eventually accountable for giving urine its characteristic yellow color.
The authors think this discovery could significantly impact our understanding of various health conditions. For example, it might shed light on the role of the gut microbiome in diseases like jaundice and inflammatory bowel disease (IBD). Patients with jaundice have a high accumulation of bilirubin, whereas lower levels of urobilin have been observed in people with IBD.
The findings appeared in the journal Nature Microbiology.
Previous studies had identified the conversion of bilirubin to urobilinogen but failed to determine the specific enzyme accountable. The current discovery of bilirubin reductase fills this knowledge space. This enzyme is produced predominantly by a group of gut germs referred to as Firmicutes, which prevail in the human gut microbiome.
These insights were revealed thanks to modern-day genomic sequencing innovations, which made it possible for researchers to compare the genomes of bacteria that can and can not convert bilirubin into urobilinogen. By doing so, they determined the gene responsible for producing bilirubin reductase. Further tests involving the model organism E. coli validated the enzymes function in this conversion.
These insights were exposed thanks to modern genomic sequencing technologies, which made it possible for researchers to compare the genomes of bacteria that can and can not convert bilirubin into urobilinogen.
While this discovery is a considerable leap forward, additional research is needed to understand how the absence of bilirubin reductase contributes to some medical conditions. In addition to jaundice and inflammatory bowel illness, the gut microbiome has actually been connected to various illness and conditions, from allergic reactions to arthritis to psoriasis.
A follow-up substantial study involving the gut microbiomes of 1,801 healthy adults revealed that nearly all individuals had germs carrying the gene for bilirubin reductase. Nevertheless, its frequency was notably lower in people with IBD and in babies under three months old, who are more susceptible to jaundice.
