硫肽素是高度修饰的硫肽抗生素,其结构与硫链丝菌素 A 相似,并具有两个不寻常的特征。所有硫肽素均含有硫代酰胺(天然产物中的稀有部分),以及硫肽素的子集,其核心大环中存在哌啶,而不是硫肽中通常观察到的氧化程度较高的脱氢哌啶或吡啶环。在这里,我们报道了链霉菌中硫肽素生物合成基因(tpn)簇的鉴定以及基因产物TpnL,其显示出与(脱氮)黄素依赖性氧化还原酶的序列相似性。 TpnL 在硫链丝菌素 A 生产者劳伦链霉菌中的异源表达导致含哌啶类似物的产生。结合研究表明,TpnL 优先结合脱氮黄素辅因子辅酶 F420,体外重建 TpnL 活性证实该酶是 F420H2 依赖性脱氢哌啶还原酶。 TpnL 及其活性的鉴定为含哌啶系列 a 硫肽奠定了基础,该系列 a 硫肽是这个多样化抗生素家族的五个主要结构组之一。
of the ring A formation of the bacterial neocarazostatin A carbazole metabolite. We provide evidence of the involvement of two unusual aromatic polyketide proteins. This finding suggests how new enzymatic activities can be recruited to specific pathways to expand biosynthetic capacities. Finally, we leveraged our bioinformatics survey to identify the untapped capacity of carbazole biosynthesis.
Methods and systems for increasing production of equilibrium reactions
申请人:Cargill, Incorporated
公开号:EP2194042A3
公开(公告)日:2012-10-31
Methods and systems for increasing the production of monatin in a multi-step equilibrium pathway are described. In some embodiments, a method includes adding alanine to a reactor along with one or more reactants and one or more enzymes, and producing a mixture comprising monatin and one or more intermediates. The addition of alanine results in a decreased concentration of less stable intermediates and an increased concentration of monatin.
The thiaminediphosphate-dependent, branched-chain 2-keto aciddecarboxylase from Lactococcus lactis sup. cremoris B1157 (KdcA) is a new valuableenzyme for the synthesis of chiral 2-hydroxy ketones. The gene was cloned and the enzyme was expressed as an N-terminal hexahistidine fusion protein in Escherichia coli. It has a broad substrate range for the decarboxylation reaction including linear and
Polypeptides and biosynthetic pathways for the production of monatin and its precursors
申请人:Abraham W. Timothy
公开号:US20050244937A1
公开(公告)日:2005-11-03
Methods and compositions that can be used to make monatin from glucose, tryptophan, indole-3-lactic acid, indole-3-pyruvate, and 2-hydroxy 2-(indol-3-ylmethyl)-4-keto glutaric acid, are provided. Methods are also disclosed for produding the indole-3-pyruvate and 2-hydroxy 2-(indol-3-ylmethyl)-4-keto glutaric acid intermediates. Compositions provided include nucleic acid molecules, polypeptides, chemical structures, and cells. Methods include in vitro and in vivo processes, and the in vitro methods include chemical reactions.
Beverage compositions comprising monatin and methods of making same
申请人:Abraham W. Timothy
公开号:US20050106305A1
公开(公告)日:2005-05-19
The present invention relates to novel beverage compositions comprising monatin and methods for making such compositions. The present invention also relates to beverage compositions comprising specific monatin stereoisomers, specific blends of monatin stereoisomers, and/or monatin produced via a biosynthetic pathway in vivo (e.g., inside cells) or in vitro.