73945-46-7Relevant articles and documents
Dynamic Kinetic Resolution for Asymmetric Synthesis of L-Noncanonical Amino Acids from D-Ser Using Tryptophan Synthase and Alanine Racemase
Yu, Jinhai,Li, Jing,Gao, Xia,Zeng, Shuiyun,Zhang, Hongjuan,Liu, Junzhong,Jiao, Qingcai
, p. 6618 - 6625 (2019/11/03)
L-Ser is often used to synthesize some significant l-noncanonical α-amino acids(l-ncAAs), which are the prevalent intermediates and precursors for functional synthetic compounds. In this study, threonine aldolase from Escherichia coli k-12 MG1655 has been used to synthesize l-Ser. In contrast to the maximum catalytic capacity (20 g/L) for l-threonine aldolase(LTA), d-Ser was synthesized with high yield (240 g/L) from cheap Gly and paraformaldehyde using d-threonine aldolase (DTA) from Arthrobacter sp ATCC. In order to fully utilize d-Ser and expand the resource of l-Ser, a dynamic kinetic resolution system was constructed to convert d/dl-Ser to l-Ser through combining alanine racemase (Alr) from Bacillus subtilis with l-tryptophan synthase (TrpS) from Escherichia coli k-12 MG1655, and l-ncAAs including l-Trp and l-Cys derivatives were synthesized with excellent enantioselectivity and in high yields. The results indicated l-ncAAs could be efficiently synthesized from d-Ser using this original and green dynamic kinetic resolution system, and the reliable l-Ser resource has been established from simple and achiral substrates.
Straightforward Regeneration of Reduced Flavin Adenine Dinucleotide Required for Enzymatic Tryptophan Halogenation
Ismail, Mohamed,Schroeder, Lea,Frese, Marcel,Kottke, Tilman,Hollmann, Frank,Paul, Caroline E.,Sewald, Norbert
, p. 1389 - 1395 (2019/02/10)
Flavin-dependent halogenases are known to regioselectively introduce halide substituents into aromatic moieties, for example, the indole ring of tryptophan. The process requires halide salts and oxygen instead of molecular halogen in the chemical halogena
Aromatic Halogenation by Using Bifunctional Flavin Reductase–Halogenase Fusion Enzymes
Andorfer, Mary C.,Belsare, Ketaki D.,Girlich, Anna M.,Lewis, Jared C.
, p. 2099 - 2103 (2017/10/07)
The remarkable site selectivity and broad substrate scope of flavin-dependent halogenases (FDHs) has led to much interest in their potential as biocatalysts. Multiple engineering efforts have demonstrated that FDHs can be tuned for non-native substrate scope and site selectivity. FDHs have also proven useful as in vivo biocatalysts and have been successfully incorporated into biosynthetic pathways to build new chlorinated aromatic compounds in several heterologous organisms. In both cases, reduced flavin cofactor, usually supplied by a separate flavin reductase (FR), is required. Herein, we report functional synthetic, fused FDH-FR proteins containing various FDHs and FRs joined by different linkers. We show that FDH-FR fusion proteins can increase product titers compared to the individual components for in vivo biocatalysis in Escherichia coli.
