Crystal structure of barley agmatine coumaroyltransferase, an N-acyltransferase from the BAHD superfamily

Abstract

The enzymes of the BAHD superfamily, a large group of acyl-CoA-dependent acyltransferases in plants, are involved in the biosynthesis of diverse secondary metabolites. While the structures of several O-acyltransferases from the BAHD superfamily, such as hydroxycinnamoyl-CoA shikimate hydroxycinnamoyl transferase, have been elucidated, no structural information on N-acyltransferases is available. Hordeum vulgare agmatine coumaroyltransferase (HvACT) is an N-acyltransferase from the BAHD superfamily and is one of the most important enzymes in the secondary metabolism of barley. Here, an apo-form structure of HvACT is reported as the first structure of an N-acyltransferase from the BAHD superfamily. HvACT crystals diffracted to 1.8 Å resolution and belonged to the monoclinic space group P21, with unit-cell parameters a = 57.6, b = 59.5, c = 73.6 Å, α = 90, β = 91.3 , γ = 90°. Like other known BAHD superfamily structures, HvACT contains two domains that adopt a two-layer αβ-sandwich architecture and a solvent-exposed channel that penetrates the enzyme core.

Loop Evolutionary Patterns Shape Catalytic Efficiency of TRI101/201 for Trichothecenes: Insights into Protein–Substrate Interactions

“…Nonetheless, the lack of comprehensive information regarding this branch has limited our exploration. Moreover, we observed that transferases with similar doughnut structures, such as BAHD superfamily enzymes (PDBID: 5KJS, 7CYS, 7W26, 8DQO,), possess comparable loop cover structures, suggesting that they may perform analogous functions in catalysis. Therefore, further research on such loop cover structures is crucial to comprehend the impact of intrinsic disordered loops on catalysis and to rationally design enzymes.…”

Analysing a Group of Homologous BAHD Enzymes Provides Insights into the Evolutionary Transition of Rosmarinic Acid Synthases from Hydroxycinnamoyl-CoA:Shikimate/Quinate Hydroxycinnamoyl Transferases

“…The protein structure models of MlAT6 were generated using the AlphaFold2 online server [34]. The molecular model revealed that MlAT6 possessed an active pocket located at the intersection of two pseudosymmetrical domains, consistent with the characteristic features of BAHD acyltransferases [35][36][37]. Subsequently, virtual docking experiments were performed to dock a p-coumaroyl-4'-hydroxyphenyllactate molecule and a p-coumaroyl shikimate molecule into the active cavity of MlAT6.…”

Family characteristics, phylogenetic reconstruction, and potential applications of the plant BAHD acyltransferase family

“…The first characterized crystal structure of N-acyltransferase (refers to the acyltransferases using nitrogenous metabolites as substrates) in the BAHD family was of Hordeum vulgare agmatine coumaroyltransferase ( Hv ACT) (PDB ID: 7CYS). The structure shares some commonality with Rs VS, that is, they both consist of two domains connected by a long and large crossover loop, but the Hv ACT contains 18 β-strands (β1–β18) and 13 α-helixes (α1–α13) ( Yamane et al., 2020 ) ( Figure 2B ). The crystal structures of BAHD members have been published one after another, and the number of described structures is currently 26 ( Garvey et al., 2008 ; Garvey et al., 2009 ; Lallemand et al., 2012 ; Manjasetty et al., 2012 ; Walker et al., 2013 ; Eudes et al., 2016b ; Levsh et al., 2016 ; Chiang et al., 2018 ).…”

“…The structure of Rs VS is reproduced according to reference reported by Ma et al. (2005) , and the structure of is Hv ACT reproduced according to reference reported Yamane et al. (2020) .…”

“…The BAHD acyltransferase family was named according to the first letter of each of the first four biochemically characterized enzymes within this family: benzylalcohol O-acetyltransferase (BEAT), anthocyanin O-hydroxycinnamoyltransferase (AHCT), anthranilate N-hydroxycinnamoyl/benzoyltransferase (HCBT), and deacetylvindoline 4-O-acetyltransferase (DAT) ( D’Auria, 2006 ). Members of the BAHD family have been reported in model plants, such as Arabidopsis, Barley, Rice, and Poplar, as well as in important medicinal and economic plants, including Pear, Chinese staff vine ( Celastrus angulatus ), Jasmine, Tea, and Taxus ( Aktar et al., 2022 ; Grienenberger et al., 2009 ; Zhang and Xu, 2018 ; Liu et al., 2020 ; Yamane et al., 2020 ; Yan et al., 2020 ; Wang et al., 2021a ; Wang et al., 2021b ; Zhao et al., 2021 ; Yuan et al., 2022 ). These BAHD proteins are involved in the formation of a variety of plant-derived active acylated natural products and their precursors, such as anthocyanins, alkaloids, aromatic alcohols/amines, aliphatic alcohols/amines, terpenoids and sugar detivatives.…”