1996 Volume 13 Pages 117-122
Selenium, an essential trace element for mammals, birds, fishes, amphibia and some bacteria, shows various remarkable biological effects, and it is definitely required in various metabolic systems such as antioxidative defence systems, hormone regulated biosynthesis, constituents of muscle and anaerobic redox catalysis. The biological significance of selenium may be related to the unique functions of various selenoproteins which contain a selenocysteine residue as an integral part of their active site. Glutathione peroxidase is one of the most extensively studied selenoenzymes, and its catalysis is closely related to the antioxidative effects of selenium. However, glutathione peroxidase and other known selenoproteins such as iodothyronine 5’-deiodinase cannot explain all the biological effects of selenium. Discovery of a new selenoprotein would give us a significant insight for further understanding the physiological roles of selenium in human health. This article introduces protocol and skills frequently used in selenium biochemistry; the use of selenium-75 in detecting and identifying selenoenzymes, chemical identification of the selenocysteine residue, and precautions in selenoprotein purification.
