In the intricate process of natural product biosynthesis,a metabolon can enhance metabolic flux by associating sequential enzymes.A fungal metabolon,comprising of flavin-dependent monooxygenase Spe F and P450 monooxyg...In the intricate process of natural product biosynthesis,a metabolon can enhance metabolic flux by associating sequential enzymes.A fungal metabolon,comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G,is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B.Using notoamide E as a substance,Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation,followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit.Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement.This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.展开更多
Metabolons are transientmulti-protein complexes of sequential enzymes that mediate substrate channeling.They differ from multi-enzyme complexes in that they are dynamic,rather than permanent,and as such have considera...Metabolons are transientmulti-protein complexes of sequential enzymes that mediate substrate channeling.They differ from multi-enzyme complexes in that they are dynamic,rather than permanent,and as such have considerably lower dissociation constants.Despite the fact that a huge number of metabolons have been suggested to exist in plants,most of these claims are erroneous as only a handful of these have been proven to channelmetabolites.We believe that physical protein-protein interactions between consecutive enzymes of a pathway should rather be called enzyme-enzyme assemblies.In this review,we describe how metabolons are generally assembled by transient interactions and held together by both structural elements and non-covalent interactions.Experimental evidence for their existence comes fromprotein-protein interaction studies,which indicate that the enzymes physically interact,and direct substrate channelingmeasurements,which indicate that they functionally interact.Unfortunately,advances in cell biology and proteomics have far outstripped those in classical enzymology and flux measurements,rendering most reports reliant purely on interactome studies.Recent developments in co-fractionation mass spectrometry will likely further exacerbate this bias.Given this,only dynamic enzyme-enzyme assemblies in which both physical and functional interactions have been demonstrated should be termed metabolons.We discuss the level of evidence for the manifold plant pathways that have been postulated to contain metabolons and then list examples in both primary and secondary metabolism for which strong evidence has been provided to support these claims.In doing so,we pay particular attention to experimental and mathematical approaches to study metabolons as well as complexities that arise in attempting to follow them.Finally,we discuss perspectives for improving our understanding of these fascinating but enigmatic interactions.展开更多
基金supported by the National Natural Science Foundation of China(U1812403 to Xiao-Jiang Hao,2193304 to Yun-Dong Wu,81573323 and 31770392 to Ying-Tong Di,and 22177050 to Ming-Ming Cao)the Project of Yunnan Characteristic Plant Screening and R&D Service CXO Platform(2022YKZY001)the Yunnan Provincial Science and Technology Department(202003AD150012 to Xiao-Jiang Hao,202201AS070040 and 202302AA310035 to Ying-Tong Di)。
文摘In the intricate process of natural product biosynthesis,a metabolon can enhance metabolic flux by associating sequential enzymes.A fungal metabolon,comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G,is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B.Using notoamide E as a substance,Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation,followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit.Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement.This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.
基金supported by funding from the Max Planck Society(Y.Z.and A.R.F.)the European Union’s Horizon 2020 research and innovation programme,project PlantaSYST(SGA-CSA no.739582 under FPA no.664620)for supporting their research.
文摘Metabolons are transientmulti-protein complexes of sequential enzymes that mediate substrate channeling.They differ from multi-enzyme complexes in that they are dynamic,rather than permanent,and as such have considerably lower dissociation constants.Despite the fact that a huge number of metabolons have been suggested to exist in plants,most of these claims are erroneous as only a handful of these have been proven to channelmetabolites.We believe that physical protein-protein interactions between consecutive enzymes of a pathway should rather be called enzyme-enzyme assemblies.In this review,we describe how metabolons are generally assembled by transient interactions and held together by both structural elements and non-covalent interactions.Experimental evidence for their existence comes fromprotein-protein interaction studies,which indicate that the enzymes physically interact,and direct substrate channelingmeasurements,which indicate that they functionally interact.Unfortunately,advances in cell biology and proteomics have far outstripped those in classical enzymology and flux measurements,rendering most reports reliant purely on interactome studies.Recent developments in co-fractionation mass spectrometry will likely further exacerbate this bias.Given this,only dynamic enzyme-enzyme assemblies in which both physical and functional interactions have been demonstrated should be termed metabolons.We discuss the level of evidence for the manifold plant pathways that have been postulated to contain metabolons and then list examples in both primary and secondary metabolism for which strong evidence has been provided to support these claims.In doing so,we pay particular attention to experimental and mathematical approaches to study metabolons as well as complexities that arise in attempting to follow them.Finally,we discuss perspectives for improving our understanding of these fascinating but enigmatic interactions.
