Amino acids are a fundamental building block for fur, muscle, and every other living tissue on Earth. These molecules come in “left-handed” (L) and “right-handed” (D) forms, a bit like gloves that fit different hands or mirror images. Life largely runs on the left-handed set, so biologists once assumed the right-handed versions were irrelevant. Yet nature quietly manufactures these D-amino acids and they can play a role in certain biological processes. In research led by Japanese analytical chemist Ren Kimura of the R&D-Analytical Science Research department of the Kao Corporation, Japan, researchers reveal that these overlooked molecules may offer an early-warning beacon for one of the most common and deadly ailments in cats, chronic kidney disease (or CKD for short), and they may even have potential in diagnosing human conditions.

Our gut contains a sleepless army, creating a hostile environment for pathogens, and helping to fortify our body’s immune defences. It may surprise you to learn that this army isn’t even human in nature, but is bacterial. The trillions of bacteria that naturally live in our gut, known as the gut microbiota, form an important component of our overall immunity against infectious disease. While bacteria can also cause disease, beneficial bacteria naturally colonise available spaces in our body, such as the gut, and play a key role in our immunity and physiology. Research conducted by Prof. Nelson Gekara of Stockholm University in Sweden and colleagues has revealed that these microscopic organisms play a crucial role in protecting us from viral infections, even in organs that are unconnected to the gut. Their study, published in the journal Immunity, uncovers a fascinating link between the gut microbiota and our body’s ability to fight viruses, offering new insights into immune function and the unintended consequences of antibiotic use.