Crystal structure of the catalytic domain of PigE: A transaminase involved in the biosynthesis of 2-methyl-3-n-amyl-pyrrole (MAP) from Serratia sp FS14
Crystal structure of the catalytic domain of PigE: A transaminase involved in the biosynthesis of 2-methyl-3-n-amyl-pyrrole (MAP) from Serratia sp FS14
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PigE 催化结构域的晶体结构：一种参与沙雷氏菌 FS14 生物合成 2-甲基-3-正戊基-吡咯 (MAP) 的转氨酶
DOI：
10.1016/j.bbrc.2014.03.125
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发表时间：
2014-04-25
影响因子：
3.1
通讯作者：
Wang, Weiwu
中科院分区：
文献类型：
--
作者：
Lou, Xiangdi;Ran, Tingting;Wang, Weiwu
灵菌红素是沙雷氏菌和其他一些微生物通过分支生物合成途径合成的三吡咯红色素，分别合成MBC（4-甲氧基-2,2'-联吡咯-5-甲醛）和MAP（2-甲基-3-正戊基-吡咯），然后通过PigC缩合形成灵菌红素。 MAP由PigD、PigE和PigB依次合成。 PigE 催化氨基转氨基至 3-乙酰辛醛的醛基，产生氨基酮，氨基酮自发环化形成 H(2)MAP。在这里，我们首次报道了参与灵菌红前体MAP生物合成的PigE催化结构域的晶体结构，分辨率为2.3埃，不对称单元中含有同型二聚体。 PigE催化结构域的单体由三个以PLP为辅因子的结构域组成：连接催化结构域和PigE前部的小N端结构域、大PLP结合结构域和C端结构域。两个单体的残基在二聚体的界面处构建了 PLP 结合位点，类似于其他 PLP 依赖性酶。 PigE与嗜热栖热菌AcOAT的结构比较显示PigE具有更高的疏水性和更小的活性位点，这些差异可能是底物特异性的原因。 (C) 2014 Elsevier Inc. 保留所有权利。
Prodigiosin, a tripyrrole red pigment synthesized by Serratia and some other microbes through a bifurcated biosynthesis pathway, MBC (4-methoxy-2,2'-bipyrrole-5-carbaldehyde) and MAP (2-methyl-3-n-amyl-pyrrole) are synthesized separately and then condensed by PigC to form prodigiosin. MAP is synthesized sequentially by PigD, PigE and PigB. PigE catalyzes the transamination of an amino group to the aldehyde group of 3-acetyloctanal, resulting in an aminoketone, which spontaneously cyclizes to form H(2)MAP. Here we report the crystal structure of the catalytic domain of PigE which involved in the biosynthesis of prodigiosin precursor MAP for the first time to a resolution of 2.3 angstrom with a homodimer in the asymmetric unit. The monomer of PigE catalytic domain is composed of three domains with PLP as cofactor: a small N-terminal domain connecting the catalytic domain with the front part of PigE, a large PLP-binding domain and a C-terminal domain. The residues from both monomers build the PLP binding site at the interface of the dimer which resembles the other PLP-dependent enzymes. Structural comparison of PigE with Thermus thermophilus AcOAT showed a higher hydrophobic and smaller active site of PigE, these differences may be the reason for substrate specificity. (C) 2014 Elsevier Inc. All rights reserved.