Isocitrate Dehydrogenase and Isocitrate Lyase are Essential Enzymes for Riboflavin Production in Ashbya gossypii

• Published in: Biotechnology and bioprocess engineering Vol. 12; no. 2; pp. 92 - 99
• Main Authors: Kanamasa, Shin, Tajima, Satoshi, Park, Enoch Y
• Format: Journal Article
• Language: Korean
• Published: 한국생물공학회 01.04.2007
• Subjects: 생물공학; NAD^+-dependent$ isocitrate dehydrogenase 1; isocitrate lyase; riboflavin production; gene disruption; Ashbya gossypii
• ISSN: 1226-8372; 1976-3816

For this study, we hypothesized that mitochondrial $NAD^+-dependent$ isocitrate dehydrogenase 1 (ICDH1) and isocitrate lyase (ICL 1) were important enzymes for riboflavin synthesis in the fungus Ashbya gossypii. Here, the genes encoding ICDH1 and ICL1 were disrupted in order to analyze the enzymes' functions on riboflavin production by the fungus. The riboflavin production resulting from these disruptants was markedly decreased compared to the concentration produced by its parental strain when cultured in a rich nutrient medium used to optimize riboflavin production. Furthermore, when comparing the transcription levels of the genes encoding ICDH1 and ICL1, between wild-type A. gossypii and an itaconate resistant mutant of A. gossypii obtained by UV irradiation, the mRNA levels in the mutant were 1.8- and 2.0-fold higher than those in the wild-type strain, respectively. These results indicate that ICDH1 and ICL1 are key enzymes for riboflavin synthesis in A. gossypii.