Tyrosine 92 of aristolochene synthase directs cyclisation of farnesyl pyrophosphateElectronic supplementary information (ESI) available: GC-profiles of co-injections of 4 from ASY92V and authentic material and mass spectra of 4 produced by ASY92V and an authentic sample. See http://www.rsc.org/suppdata/cc/b2/b206517g/
作者:Melanie J. Calvert、Susan E. Taylor、Rudolf K. Allemann
DOI:10.1039/b206517g
日期:2002.10.11
A mutant of Aristolochene Synthase (AS), in which Tyr 92 was replaced by Val, produced the alicyclic beta-(E)-farnesene as the major product, indicating that cyclisation of FPP is controlled by Tyr 92 in AS.
Templating effects in aristolochene synthase catalysis: elimination versus cyclisation
作者:Juan A. Faraldos、Verónica González、Michael Senske、Rudolf K. Allemann
DOI:10.1039/c1ob06184d
日期:——
Analysis of the products generated by mutants of aristolochene synthase from P. roqueforti (PR-AS) revealed the prominent structural role played by the aliphatic residue Leu 108 in maintaining the productive conformation of farnesyl diphosphate to ensure C1–C10 (σ-bond) ring-closure and hence (+)-aristolochene production.
通过分析藜芦属植物马兜铃烯合成酶(PR-AS)突变体产生的产物,发现脂肪族残基 Leu 108 在维持二磷酸法呢基的生产构象以确保 C1-C10(σ-键)环闭合从而产生 (+)- 马兜铃烯方面发挥着重要的结构作用。
Aristolochene Synthase: Mechanistic Analysis of Active Site Residues by Site-Directed Mutagenesis
作者:Brunella Felicetti、David E. Cane
DOI:10.1021/ja0499593
日期:2004.6.1
(-)-valencene (5) in a 94:4:2 ratio. By contrast, the closely related aristolochene synthase from Aspergillus terreus cyclized farnesyl diphosphate only to (+)-aristolochene (4). Site-directedmutagenesis of amino acid residues in two highly conserved Mg(2+)-binding domains led in most cases to reductions in both k(cat) and k(cat)/K(m) as well as increases in the proportion of (S)-(-)germacrene A (2)
Stabilisation of eudesmane cation by tryptophan 334 during aristolochene synthase catalysisElectronic Supplementary Information (ESI) available: GC profiles of co-injections of germacrene A from ASW334F and ASW334V with authentic germacrene A; mass spectra of germacrene A produced by ASW334V and of an authentic sample; mass spectra of valencene produced by ASW334F and of an authentic sample. See http://www.rsc.org/suppdata/cc/b3/b306867f/
作者:Athina Deligeorgopoulou、Susan E. Taylor、Silvia Forcat、Rudolf K. Allemann
DOI:10.1039/b306867f
日期:——
Analysis of the hydrocarbons produced during catalysis by mutants of aristolochene synthase from Penicillium roqueforti indicated that Trp 334 had a pivotal function for the efficient production of aristolochene from farnesylpyrophosphate most likely by stabilising the intermediate, eudesmane cation.
Stabilisation of transition states prior to and following eudesmane cation in aristolochene synthase
作者:Silvia Forcat、Rudolf K. Allemann
DOI:10.1039/b604147g
日期:——
The mechanistic details of the cyclisation of farnesylpyrophosphate (FPP) by aristolochene synthase (AS) from Penicillium roqueforti have only recently begun to emerge, mainly through the analysis of the reaction products generated by AS-mutants. The reaction proceeds through several intermediates including germacrene A and eudesmane cation. Previous work suggested that the side chain of phenylalanine 178 promoted the conversion of eudesmane cation to aristolochene. We now report that the catalytic function of this residue during the conversion of eudesmane cation to aristolochene is mainly due to the large size of its side chain, which facilitates the hydride shift from C2 to C3, rather than its aromatic character. In addition, F178 appears to control the regioselectivity of the final deprotonation step and, together with F112, helps stabilise the developing positive charge on C1 after the expulsion of pyrophosphate from the substrate. These results complete a screen of likely active-site aromatic residues and establish their respective roles in the conversion of FPP to aristolochene.
主要通过分析 AS 突变体产生的反应产物,人们最近才开始了解到花青素合成酶(AS)环化焦磷酸芳樟酯(FPP)的机理细节。该反应通过几个中间产物进行,其中包括革兰氏烯 A 和桉叶烷阳离子。以前的研究表明,苯丙氨酸 178 的侧链促进了桉叶烷阳离子向马兜铃烯的转化。我们现在报告说,在桉叶烷阳离子转化为马兜铃烯的过程中,该残基的催化作用主要是由于其侧链的大尺寸,这有利于氢化物从 C2 转移到 C3,而不是其芳香特性。此外,F178 似乎还能控制最后去质子化步骤的区域选择性,并与 F112 一起,在焦磷酸从底物中排出后,帮助稳定 C1 上正在形成的正电荷。这些结果完成了对可能的活性位点芳香残基的筛选,并确定了它们各自在 FPP 转化为马兜铃烯过程中的作用。