Characterization of acetolactate decarboxylase of Streptococcus thermophilus and its stereoselectivity in decarboxylation of α-hydroxy-β-ketoacids
作者:Zi-Qi Zheng、Cai-Yun Luo、Han Chen、Huan Sun、Xian Hui、Zi-Dong Chen、Wen-Yun Gao、Heng Li
DOI:10.1016/j.bioorg.2022.105719
日期:2022.5
catabolic enzyme catalyzes the decarboxylation of (±)-acetolactate to produce a single product, (R)-acetoin. It can also convert other racemic α-hydroxy-β-ketoacids to corresponding α -hydroxyketones in R-configuration. In this work, we prepared ALDC of Streptococcus thermophilus (StALDC) and explored its stereoselectivity on different substrates. The enzyme displays no enantioselectivity on substrate
乙酰乳酸脱羧酶 (ALDC) 是一种充分表征的分解代谢酶,可催化 (±)-乙酰乳酸脱羧生成单一产物 ( R )-乙偶姻。它还可以将其他外消旋的α-羟基-β-酮酸转化为相应的R-构型的α-羟基酮。在这项工作中,我们制备了嗜热链球菌(StALDC) 的 ALDC,并探索了它在不同底物上的立体选择性。该酶对底物 (±)-乙酰乳酸不显示对映选择性,但对产物乙偶姻显示R-选择性,这与各种 ALDC 报告的数据相同。然而,当化合物 (±) - 2-propionyl-2-hydroxybutyrate 用作底物时,酶表现出S-对底物和产物均具有选择性,即只能将( S ) -2-丙酰基-2-羟基丁酸脱羧生成( S ) -4-羟基-3-己酮,而不是其R-异构体,这完全不同于为枯草芽孢杆菌ALDC 公布的数据。据我们所知,这是首次报道ALDC的底物依赖性对映选择性,并在同源性建模和分子对接实验的基础上讨论了StALDC的特征。
Enantioselective Intermolecular Aldehyde-Ketone Cross-Coupling through an Enzymatic Carboligation Reaction
substrate tolerance of the enzyme is very broad and includes cyclic and open‐chain ketones, as well as diketones and α‐ and β‐ketoesters as acceptor substrates. The absolute configurations of two enzymatic products were determined by single‐crystal structure analysis.
Happy new YerE:标题反应的第一个例子是使用 ThDP 依赖性酶催化剂呈现的。该酶的底物耐受性非常广泛,包括环状和开链酮,以及作为受体底物的二酮和 α- 和 β-酮酯。通过单晶结构分析确定两种酶产物的绝对构型。
TRICYCLIC HETEROCYCLIC COMPOUNDS, COMPOSITIONS AND METHODS OF USE THEREOF
申请人:Babu Srinivasan
公开号:US20110201593A1
公开(公告)日:2011-08-18
The invention provides novel compounds of formula I having the general formula:
wherein R
1
, R
2
, R
3
, X and Y are as described herein. Accordingly, the compounds may be provided in pharmaceutically acceptable compositions and used for the treatment of immunological or hyperproliferative disorders.
Complete Biosynthetic Pathway of the Phosphonate Phosphonothrixin: Two Distinct Thiamine Diphosphate-Dependent Enzymes Divide the Work to Form a C–C Bond
catalyzes the transfer of a two-carbon unit attached to the thiamine diphosphate (TPP) cofactor (provided by the acetohydroxyacid synthase homologue, PtxB7) to HOPA to produce PTX. This study reveals a unique C–C bond formation in which two distinct TPP-dependent enzymes, PtxB5/6 and PtxB7, divide the work to transfer an acetyl group, highlighting an unprecedented biosynthetic strategy for natural products