Flavoproteins are proteins that contain a nucleic acid derivative of riboflavin: flavin adenine dinucleotide (FAD) or flavin mononucleotide (FMN). Flavoproteins are involved in a wide array of biological processes, such as photosynthesis, DNA repair and natural product biosynthesis. It should be noted that 5%-10% of flavoproteins have a covalently linked flavin prosthetic group. Such covalent linkages benefit the holoenzyme in several ways including improving the stability and catalytic potency. During the past decade, significant progress has been made in covalent flavoproteins, especially with respect to enzyme-dependent biogenesis and discovery of novel linkage types. The present review gives a condensed overview of investigations published from March 2009 to December 2021, with emphasis on the discovery, biogenesis and their catalytic role in natural product biosynthesis.
Flavoproteins/metabolism* ; Flavin-Adenine Dinucleotide/metabolism* ; Flavin Mononucleotide/metabolism* ; Riboflavin ; Biological Products

Riboflavin is a constituent of coenzyme, FMN, FAD and its content varies according to the physiological and nutritional status. However, the measurement of its content is so disputable that a new technique to determine its content has been developed, done by determination of glutathione reductase activity in red blood cell hemolysate. With this technique, the effect of various anesthetic agents (ether, halothane, tetracaine) upon riboflavin metabolism has been studied by the authors. In conclusion, the effects of anesthetics upon riboflavin metabolism are insignificant.
Anesthetics ; Erythrocytes* ; Flavin Mononucleotide ; Flavin-Adenine Dinucleotide ; Glutathione Reductase ; Glutathione* ; Halothane ; Metabolism ; Nutritional Status ; Riboflavin