Summary
Two unnatural and unwanted amino acids, norvaline (Nva) and O-ethylhomoserine (O-EH) are formed as by-products in l-isoleucine production by Brevibacterium flavum AB-07 using a new process named the living cell reaction process. Nva formation was depressed by using a leucine auxotrophic mutant (AB-07-Leu-2) derived from strain AB-07. It was found that Nva formation was closely related to leucine biosynthesis. O-EH formation was repressed by addition of l-methionine to the reaction mixture. However, the homoserine-O-acetyltransferase of AB-07-Leu-2 was not subject to either inhibition or repression by addition of l-methionine. Furthermore, the O-EH-forming enzyme, which converts O-acetylhomoserine to O-EH, was speculated to be repressed by l-methionine.
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References
Bradford MM (1976) A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem 72:248–254
Eggeling I, Sahm H (1987) Regulation of acetohydroxy acid synthase in Corynebacterium glutamicum during fermentation of α-ketobutyrate to l-isoleucine. Appl Microbiol Biotechnol 25:346–351
Hill DW, Walters FH, Wilson TD, Stuart JD (1979) High performance liquid chromarographic determination of amino acids in the picomole range. Anal Chem 51:1338–1341
Ikeda S, Fujita I, Yoshinaga F (1976) Screening of l-isoleucine producers among ethionine resistant mutants of l-threonine producing bacteria. Agric Biol Chem 40:511–516
Kase H, Nakayama K (1975) O-Alkylhomoserine as an intermediate in methionine biosynthesis in Arthrobacter paraffineus, Corynebacterium glutamicum and Bacillus species. Agric Biol Chem 39:687–693
Kisumi M, Kato J, Komatsubara S, Chibata I (1971a) Increase in isoleucine accumulation by α-aminobutyric acid-resistant mutants of Serratia marcescens. Appl Microbiol 21:569–574
Kisumi M, Komatsubara S, Suguira M, Chibata I (1971b) Properties of isoleucine hydroxamate-resistant mutants of Serratia marcescens. J Gen Microbiol 69:291–297
Kisumi M, Sugiura M, Chibata I (1976a) Biosynthesis of norvaline, norleucine, and homoisoleucine in Serratia marcescens. J Biochem 80:333–339
Kisumi M, Sugiura M, Kato J, Chibata I (1976b) l-Norvaline and l-homoisoleucine formation by Serratia marcescens. J Biochem 79:1021–1028
Kohlaw GB, Leary TR (1970) α-Isopropylmalate synthase (Salmonella typhimurium). In: Tabor H, Tabor CW (eds) Methods in Enzymology, vol 17A. Academic Press, New York, pp 771–777
Miyajima R, Shiio I (1973) Regulation of aspartate family amino acid biosynthesis in Brevibacterium flavum. VII. Properties of homoserine O-transacetylase. J Biochem 73:1061–1068
Murooka Y, Harada T (1968) Fermentation of O-ethylhomoserine by bacteria. J Bacteriol 96:314–317
Murooka Y, Seto K, Harada T (1970) O-Alkylhomoserine synthesis from O-acetylhomoserine and alcohol. Biochem Biophys Res Commn 41:407–414
Murooka Y, Kakihara K, Miwa T, Seto K, Harada T (1977) O-Alkylhomoserine synthesis catalyzed by O-acetylhomoserine sulfhydrylase in microorganism. J Bacteriol 130:62–73
Nagai S, Flavin M (1967) Acetylhomoserine: an intermediate in the fungal biosynthesis of methionine. J Biol Chem 242:3884–3895
Shiio I, Sasaki A, Nakamori S, Sano K (1973) Production of l-isoleucine by AHV resistant mutants of Brevibacterium flavum. Agric Biol Chem 37:2053–2061
Terasawa M, Kakinura N, Shikata K, Yukawa H (1989) New process for l-isoleucine production. Process Biochem 24:60–61
Terasawa M, Inui M, Goto M, Shikata K, Imanari M, Yukawa H (1990) Living cell reaction process for l-isoleucine and l-valine production. J Ind Microbiol 5:289–293
Wilhelm C, Eggeling I, Nassenstein A, Jebsen C, Eggeling L, Sahm H (1989) Limitations during hydroxybutyrate conversion to isoleucine with Corynebacterium glutamicum, as analyzed by the formation of by-products. Appl Microbiol Biotechnol 31:458–462
Yukawa H, Terasawa M (1986) l-Isoleucine production by ethanol utilizing micro-organism. Process Biochem 21:196–199
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Terasawa, M., Inui, M., Goto, M. et al. Depression of by-product formation during l-isoleucine production by a living-cell reaction process. Appl Microbiol Biotechnol 35, 348–351 (1991). https://doi.org/10.1007/BF00172724
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DOI: https://doi.org/10.1007/BF00172724