|
type |
Journal Article |
authors |
Wu L, Tong MH, Raab A, Fang Q, Wang S, Kyeremeh K, Yu Y, Deng H
|
title |
An unusual metal-bound 4-fluorothreonine transaldolase from Streptomyces sp. MA37 catalyses promiscuous transaldol reactions |
journal |
Appl Microbiol Biotechnol |
Activity |
2.2.1.8 |
Family |
2.2.1.8 |
sel |
selected |
ui |
32140842 |
year |
(2020) |
pages |
in press |
| |
keywords |
4-fluorothreonine; 4-fluorothreonine transaldolase; Streptomyces sp. MA37; Transaldolation; β-Hydroxy-α-amino acids |
abstract |
β-Hydroxy-α-amino acids (βH-AAs) are key components of many bioactive molecules as well as exist as specialised metabolites. Among these βH-AAs, 4-fluorothreonine (4-FT) is the only naturally occurring fluorinated AA discovered thus far. Here we report overexpression and biochemical characterisation of 4-fluorothreonine transaldolase from Streptomyces sp. MA37 (FTaseMA), a homologue of FTase previously identified in the biosynthesis of 4-FT in S. cattleya. FTaseMA displays considerable substrate plasticity to generate 4-FT as well as other β-hydroxy-α-amino acids with various functionalities at C4 position, giving the prospect of new chemo-enzymatic applications. The enzyme has a hybrid of two catalytic domains, serine hydroxymethyltransferase (S) and aldolase (A). Site-directed mutagenesis allowed the identification of the key residues of FTases, suggesting that the active site of A domain has a historical reminiscent feature in metal-dependent aldolases. Elemental analysis demonstrated that FTaseMA is indeed a Zn2+-dependent enzyme, the first example of pyridoxal phosphate (PLP) enzyme family fused with a metal-binding domain carrying out a distinct catalytic role. Finally, FTaseMA showed divergent evolutionary origin with other PLP dependent enzymes. |
last changed |
2020/03/07 15:15 |
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