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Đulović A, Usanović K, Kukoč Modun L, Blažević I. Selenium Biofortification Effect on Glucosinolate Content of Brassica oleracea var. italic and Eruca vesicaria. Molecules 2023; 28:7203. [PMID: 37894683 PMCID: PMC10609431 DOI: 10.3390/molecules28207203] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/18/2023] [Accepted: 10/19/2023] [Indexed: 10/29/2023] Open
Abstract
Glucosinolates (GSLs) in different plant parts of broccoli (Brassica oleracea var. italic) and rocket (Eruca vesicaria) were analyzed qualitatively and quantitatively before and after treatment with sodium selenate (2 and 5 mM), by their desulfo-counterparts using the UHPLC-DAD-MS/MS technique. Twelve GSLs were detected in broccoli (five aliphatic, one arylaliphatic, and six indolic), where 4-(methylsulfanyl)butyl GSL (glucoerucin) was the main one in the roots (4.88-9.89 µmol/g DW), 4-(methylsulfinyl)butyl GSL (glucoraphanin) in stems (0.44-1.11 µmol/g DW), and 4-hydroxyindol-3-ylmethyl GSL (4-hydroxyglucobrassicin) in leaves (0.51-0.60 µmol/g DW). No GSL containing selenium was detected in the treated broccoli. Ten GSLs were detected in rocket (seven aliphatic and three indolic), where 4-(methylsulfanyl)butyl GSL (glucoerucin) was the main one in the roots (4.50-20.59 µmol/g DW) and 4-methoxyindol-3-ylmethyl GSL (4-methoxyglucobrassicin) in the aerial part (0.57-5.69 µmol/g DW). As a result of induced stress by selenium fertilization, the total GSL content generally increased in both plants. In contrast to broccoli, the roots and the aerial part of the rocket treated with a high concentration of sodium selenate contained 4-(methylseleno)butyl GSL (glucoselenoerucin) (0.36-4.48 µmol/g DW). Although methionine-derived GSLs are the most abundant in both plants, the plants' ability to tolerate selenate and its regulation by selenoglucosinolate production is species- and growth-stage-dependent.
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Affiliation(s)
- Azra Đulović
- Department of Organic Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21000 Split, Croatia; (A.Đ.); (K.U.)
| | - Katarina Usanović
- Department of Organic Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21000 Split, Croatia; (A.Đ.); (K.U.)
| | - Lea Kukoč Modun
- Department of Analytical Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21000 Split, Croatia;
| | - Ivica Blažević
- Department of Organic Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21000 Split, Croatia; (A.Đ.); (K.U.)
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Qin H, King GJ, Borpatragohain P, Zou J. Developing multifunctional crops by engineering Brassicaceae glucosinolate pathways. PLANT COMMUNICATIONS 2023:100565. [PMID: 36823985 PMCID: PMC10363516 DOI: 10.1016/j.xplc.2023.100565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 02/15/2023] [Accepted: 02/20/2023] [Indexed: 06/18/2023]
Abstract
Glucosinolates (GSLs), found mainly in species of the Brassicaceae family, are one of the most well-studied classes of secondary metabolites. Produced by the action of myrosinase on GSLs, GSL-derived hydrolysis products (GHPs) primarily defend against biotic stress in planta. They also significantly affect the quality of crop products, with a subset of GHPs contributing unique food flavors and multiple therapeutic benefits or causing disagreeable food odors and health risks. Here, we explore the potential of these bioactive functions, which could be exploited for future sustainable agriculture. We first summarize our accumulated understanding of GSL diversity and distribution across representative Brassicaceae species. We then systematically discuss and evaluate the potential of exploited and unutilized genes involved in GSL biosynthesis, transport, and hydrolysis as candidate GSL engineering targets. Benefiting from available information on GSL and GHP functions, we explore options for multifunctional Brassicaceae crop ideotypes to meet future demand for food diversification and sustainable crop production. An integrated roadmap is subsequently proposed to guide ideotype development, in which maximization of beneficial effects and minimization of detrimental effects of GHPs could be combined and associated with various end uses. Based on several use-case examples, we discuss advantages and limitations of available biotechnological approaches that may contribute to effective deployment and could provide novel insights for optimization of future GSL engineering.
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Affiliation(s)
- Han Qin
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
| | - Graham J King
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW, Australia
| | | | - Jun Zou
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
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Đulović A, Popović M, Burčul F, Čikeš Čulić V, Marijan S, Ruščić M, Anđelković N, Blažević I. Glucosinolates of Sisymbrium officinale and S. orientale. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27238431. [PMID: 36500524 PMCID: PMC9736730 DOI: 10.3390/molecules27238431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/22/2022] [Accepted: 11/29/2022] [Indexed: 12/05/2022]
Abstract
Glucosinolates (GSLs) from Sysimbrium officinale and S. orientale were analyzed qualitatively and quantitatively by their desulfo-counterparts using UHPLC-DAD-MS/MS. Eight GSLs were identified in S. officinale, including Val-derived (glucoputranjivin) and Trp-derived (4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin, and neoglucobrassicin) as the major ones followed by Leu-derived (Isobutyl GSL), Ile-derived (glucocochlearin) and Phe/Tyr-derived (glucosinalbin). Different S. orientale plant parts contained six GSLs, with Met-derived (progoitrin, epiprogoitrin, and gluconapin) and homoPhe-derived (gluconasturtiin) as the major ones, followed by glucosinalbin and neoglucobrassicin. GSL breakdown products obtained by hydrodistillation (HD) and microwave-assisted distillation from S. officinale, as well as isopropyl isothiocyanate, as the major volatile in both isolates, were tested for their cytotoxic activity using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Generally, all volatile isolates showed similar activity toward the three cancer cell lines. The best activity was shown by isopropyl isothiocyanate at a concentration of 100 µg/mL after 72 h of incubation, with 53.18% for MDA-MB-231, 56.61% for A549, and 60.02% for the T24 cell line.
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Affiliation(s)
- Azra Đulović
- Department of Organic Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21000 Split, Croatia
| | - Marijana Popović
- Department of Organic Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21000 Split, Croatia
| | - Franko Burčul
- Department of Analytical Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21000 Split, Croatia
| | | | - Sandra Marijan
- School of Medicine, University of Split, Šoltanska 2, 21000 Split, Croatia
| | - Mirko Ruščić
- Department of Biology, Faculty of Science, University of Split, Ruđera Boškovića 33, 21000 Split, Croatia
| | - Nikolina Anđelković
- Department of Organic Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21000 Split, Croatia
| | - Ivica Blažević
- Department of Organic Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21000 Split, Croatia
- Correspondence: ; Tel.: +385-21-329-434
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Agerbirk N, Pattison DI, Mandáková T, Lysak MA, Montaut S, Staerk D. Ancient Biosyntheses in an Oil Crop: Glucosinolate Profiles in Limnanthes alba and Its Relatives (Limnanthaceae, Brassicales). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:1134-1147. [PMID: 35061395 DOI: 10.1021/acs.jafc.1c07299] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The glucosinolate (GSL) profiles of four Limnanthaceae species, including the oil crop Limnanthes alba (meadowfoam), were investigated by an ultrahigh-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UHPLC-QToF-MS/MS) analysis of desulfoGSLs after desulfation of native GSLs, supplemented by NMR of desulfated 2-hydroxy-2-methylpropylGSL and 3-methoxybenzylGSL. Leaves, roots, and seeds were investigated, providing an overview of biosynthetic capabilities in the genera Floerkea and Limnanthes. Methoxyl groups on benzylGSLs were in meta but not para positions; two 3,5-disubstituted benzylGSLs are tentatively proposed. 2-Hydroxy-2-methylpropylGSL was accompanied by an isomer that was not a previously reported GSL. The combined GSL profile of the family included GSLs derived from valine, leucine, isoleucine, phenylalanine, and tyrosine, and possibly methionine and tryptophan. Substituted indole GSLs and GSLs derived from chain-elongated amino acids or alanine were searched for but not detected. Hypothetic glycosides of GSLs were detected at low levels. Based on biochemical interpretation, we suggest biosynthetic schemes and gene families (CYP79C, GSOH) relevant for tailoring GSL profiles in Limnanthes crops.
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Affiliation(s)
- Niels Agerbirk
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - David I Pattison
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Terezie Mandáková
- CEITEC─Central European Institute of Technology, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Martin A Lysak
- CEITEC─Central European Institute of Technology, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Sabine Montaut
- Biomolecular Sciences Programme, School of Natural Sciences, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6, Canada
| | - Dan Staerk
- Department of Drug Design and Pharmacology, University of Copenhagen, Jagtvej 162, 2100 Copenhagen, Denmark
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Đulović A, Burčul F, Čulić VČ, Ruščić M, Brzović P, Montaut S, Rollin P, Blažević I. Lepidium graminifolium L.: Glucosinolate Profile and Antiproliferative Potential of Volatile Isolates. Molecules 2021; 26:molecules26175183. [PMID: 34500622 PMCID: PMC8434519 DOI: 10.3390/molecules26175183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/19/2021] [Accepted: 08/23/2021] [Indexed: 11/18/2022] Open
Abstract
Glucosinolates (GSLs) from Lepidium graminifolium L. were analyzed qualitatively and quantitatively by their desulfo-counterparts using UHPLC-DAD-MS/MS technique and by their volatile breakdown products-isothiocyanates (ITCs) using GC-MS analysis. Thirteen GSLs were identified with arylaliphatic as the major ones in the following order: 3-hydroxybenzyl GSL (glucolepigramin, 7), benzyl GSL (glucotropaeolin, 9), 3,4,5-trimethoxybenzyl GSL (11), 3-methoxybenzyl GSL (glucolimnanthin, 12), 4-hydroxy-3,5-dimethoxybenzyl GSL (3,5-dimethoxysinalbin, 8), 4-hydroxybenzyl GSL (glucosinalbin, 6), 3,4-dimethoxybenzyl GSL (10) and 2-phenylethyl GSL (gluconasturtiin, 13). GSL breakdown products obtained by hydrodistillation (HD) and CH2Cl2 extraction after hydrolysis by myrosinase for 24 h (EXT) as well as benzyl ITC were tested for their cytotoxic activity using MTT assay. Generally, EXT showed noticeable antiproliferative activity against human bladder cancer cell line UM-UC-3 and human glioblastoma cell line LN229, and can be considered as moderately active, while IC50 of benzyl ITC was 12.3 μg/mL, which can be considered as highly active.
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Affiliation(s)
- Azra Đulović
- Department of Organic Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21000 Split, Croatia; (A.Đ.); (P.B.)
| | - Franko Burčul
- Department of Analytical Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21000 Split, Croatia;
| | | | - Mirko Ruščić
- Department of Biology, Faculty of Science, University of Split, Ruđera Boškovića 33, 21000 Split, Croatia;
| | - Petra Brzović
- Department of Organic Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21000 Split, Croatia; (A.Đ.); (P.B.)
| | - Sabine Montaut
- Biomolecular Sciences Programme, School of Biological, Chemical and Forensic Sciences, Laurentian University, 935 Ramsey Lake Road, Sudbury, ON P3E 2C6, Canada;
| | - Patrick Rollin
- Institut de Chimie Organique et Analytique, Université d’Orléans et CNRS, UMR 7311, 45000 Orléans, France;
| | - Ivica Blažević
- Department of Organic Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21000 Split, Croatia; (A.Đ.); (P.B.)
- Correspondence: ; Tel.: +385-21-329-434
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Trabelcy B, Chinkov N, Samuni-Blank M, Merav M, Izhaki I, Carmeli S, Gerchman Y. Investigation of glucosinolates in the desert plant Ochradenus baccatus (Brassicales: Resedaceae). Unveiling glucoochradenin, a new arabinosylated glucosinolate. PHYTOCHEMISTRY 2021; 187:112760. [PMID: 33839520 DOI: 10.1016/j.phytochem.2021.112760] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/21/2021] [Accepted: 03/25/2021] [Indexed: 06/12/2023]
Abstract
Here we describe the structure elucidation and quantification of six glucosinolates (GSLs) from the roots of the desert plant Ochradenus baccatus, Delile 1813 (family Resedaceae; order Brassicales). The structure elucidation was established on the corresponding enzymatically desulfated derivatives of the native GSLs of the plant. Among these GSLs we describe the previously undescribed 2″-O-(α-L-arabinopyranosyloxy)benzylglucosinolate (1a), for which we propose the name glucoochradenin. The other five glucosinolates (2a-6a) were (2S)-2-hydroxy-2-phenylethylglucosinolate (2a; glucobarbarin), 2″-O-(α-L-rhamnopyranosyloxy)benzylglucosinolate (3a), benzylglucosinolate (4a; glucotropaeolin), indol-3-ylmethylglucosinolate (5a; glucobrassicin) and phenethylglucosinolate (6a; gluconasturtiin), all elucidated as their desulfo-derivatives, 2b-6b respectively). Structures were elucidated by MS and 1D and 2D-NMR techniques, the identity of the arabinose verified by ion chromatography, and the absolute configuration of the sugar units determined by hydrolysis, coupling to cysteine methyl-ester and phenyl isothiocyanate followed by HPLC-MS analysis of the resulted diastereomers. Response factors were generated for desulfo-2″-O-(α-L-arabinopyranosyloxy)benzylglucosinolate and for desulfo-2″-O-(α-L-rhamnopyranosyloxy)benzylglucosinolate and all six GSLs were quantified, indicating that the root of O. baccatus is rich in GSLs (Avg. 61.3 ± 10.0 μmol/g DW and up to 337.2 μmol/g DW).
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Affiliation(s)
- Beny Trabelcy
- Department of Environmental and Evolutionary Biology, Faculty of Natural Sciences, University of Haifa, Haifa, 3498838, Israel
| | - Nicka Chinkov
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Campus Oranim, Kiryat Tivon, 36006, Israel
| | - Michal Samuni-Blank
- Department of Environmental and Evolutionary Biology, Faculty of Natural Sciences, University of Haifa, Haifa, 3498838, Israel
| | - Mayan Merav
- Raymond and Beverly Sackler School of Chemistry and Faculty of Exact Sciences, Tel Aviv University Tel Aviv University, 69978, Israel
| | - Ido Izhaki
- Department of Environmental and Evolutionary Biology, Faculty of Natural Sciences, University of Haifa, Haifa, 3498838, Israel
| | - Shmuel Carmeli
- Raymond and Beverly Sackler School of Chemistry and Faculty of Exact Sciences, Tel Aviv University Tel Aviv University, 69978, Israel
| | - Yoram Gerchman
- Department of Environmental and Evolutionary Biology, Faculty of Natural Sciences, University of Haifa, Haifa, 3498838, Israel; Oranim College, Campus Oranim, Kiryat Tivon, 36006, Israel.
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Agerbirk N, Hansen CC, Olsen CE, Kiefer C, Hauser TP, Christensen S, Jensen KR, Ørgaard M, Pattison DI, Lange CBA, Cipollini D, Koch MA. Glucosinolate profiles and phylogeny in Barbarea compared to other tribe Cardamineae (Brassicaceae) and Reseda (Resedaceae), based on a library of ion trap HPLC-MS/MS data of reference desulfoglucosinolates. PHYTOCHEMISTRY 2021; 185:112658. [PMID: 33744557 DOI: 10.1016/j.phytochem.2021.112658] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 12/30/2020] [Accepted: 01/03/2021] [Indexed: 06/12/2023]
Abstract
A library of ion trap MS2 spectra and HPLC retention times reported here allowed distinction in plants of at least 70 known glucosinolates (GSLs) and some additional proposed GSLs. We determined GSL profiles of selected members of the tribe Cardamineae (Brassicaceae) as well as Reseda (Resedaceae) used as outgroup in evolutionary studies. We included several accessions of each species and a range of organs, and paid attention to minor peaks and GSLs not detected. In this way, we obtained GSL profiles of Barbarea australis, Barbarea grayi, Planodes virginica selected for its apparent intermediacy between Barbarea and the remaining tribe and family, and Rorippa sylvestris and Nasturtium officinale, for which the presence of acyl derivatives of GSLs was previously untested. We also screened Armoracia rusticana, with a remarkably diverse GSL profile, the emerging model species Cardamine hirsuta, for which we discovered a GSL polymorphism, and Reseda luteola and Reseda odorata. The potential for aliphatic GSL biosynthesis in Barbarea vulgaris was of interest, and we subjected P-type and G-type B. vulgaris to several induction regimes in an attempt to induce aliphatic GSL. However, aliphatic GSLs were not detected in any of the B. vulgaris types. We characterized the investigated chemotypes phylogenetically, based on nuclear rDNA internal transcribed spacer (ITS) sequences, in order to understand their relation to the species B. vulgaris in general, and found them to be representative of the species as it occurs in Europe, as far as documented in available ITS-sequence repositories. In short, we provide GSL profiles of a wide variety of tribe Cardamineae plants and conclude aliphatic GSLs to be absent or below our limit of detection in two major evolutionary lines of B. vulgaris. Concerning analytical chemistry, we conclude that availability of authentic reference compounds or reference materials is critical for reliable GSL analysis and characterize two publicly available reference materials: seeds of P. virginica and N. officinale.
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Affiliation(s)
- Niels Agerbirk
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark.
| | - Cecilie Cetti Hansen
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Carl Erik Olsen
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Christiane Kiefer
- Department of Biodiversity and Plant Systematics, Centre for Organismal Studies, Heidelberg University, 69120, Heidelberg, Germany
| | - Thure P Hauser
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Stina Christensen
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Karen R Jensen
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Marian Ørgaard
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - David I Pattison
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Conny Bruun Asmussen Lange
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Don Cipollini
- Department of Biological Sciences, Wright State University, 3640 Colonel Glenn Highway, Dayton, OH, 45435, USA
| | - Marcus A Koch
- Department of Biodiversity and Plant Systematics, Centre for Organismal Studies, Heidelberg University, 69120, Heidelberg, Germany
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Agerbirk N, Hansen CC, Kiefer C, Hauser TP, Ørgaard M, Asmussen Lange CB, Cipollini D, Koch MA. Comparison of glucosinolate diversity in the crucifer tribe Cardamineae and the remaining order Brassicales highlights repetitive evolutionary loss and gain of biosynthetic steps. PHYTOCHEMISTRY 2021; 185:112668. [PMID: 33743499 DOI: 10.1016/j.phytochem.2021.112668] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 01/05/2021] [Accepted: 01/09/2021] [Indexed: 06/12/2023]
Abstract
We review glucosinolate (GSL) diversity and analyze phylogeny in the crucifer tribe Cardamineae as well as selected species from Brassicaceae (tribe Brassiceae) and Resedaceae. Some GSLs occur widely, while there is a scattered distribution of many less common GSLs, tentatively sorted into three classes: ancient, intermediate and more recently evolved. The number of conclusively identified GSLs in the tribe (53 GSLs) constitute 60% of all GSLs known with certainty from any plant (89 GSLs) and apparently unique GSLs in the tribe constitute 10 of those GSLs conclusively identified (19%). Intraspecific, qualitative GSL polymorphism is known from at least four species in the tribe. The most ancient GSL biosynthesis in Brassicales probably involved biosynthesis from Phe, Val, Leu, Ile and possibly Trp, and hydroxylation at the β-position. From a broad comparison of families in Brassicales and tribes in Brassicaceae, we estimate that a common ancestor of the tribe Cardamineae and the family Brassicaceae exhibited GSL biosynthesis from Phe, Val, Ile, Leu, possibly Tyr, Trp and homoPhe (ancient GSLs), as well as homologs of Met and possibly homoIle (intermediate age GSLs). From the comparison of phylogeny and GSL diversity, we also suggest that hydroxylation and subsequent methylation of indole GSLs and usual modifications of Met-derived GSLs (formation of sulfinyls, sulfonyls and alkenyls) occur due to conserved biochemical mechanisms and was present in a common ancestor of the family. Apparent loss of homologs of Met as biosynthetic precursors was deduced in the entire genus Barbarea and was frequent in Cardamine (e.g. C. pratensis, C. diphylla, C. concatenata, possibly C. amara). The loss was often associated with appearance of significant levels of unique or rare GSLs as well as recapitulation of ancient types of GSLs. Biosynthetic traits interpreted as de novo evolution included hydroxylation at rare positions, acylation at the thioglucose and use of dihomoIle and possibly homoIle as biosynthetic precursors. Biochemical aspects of the deduced evolution are discussed and testable hypotheses proposed. Biosyntheses from Val, Leu, Ile, Phe, Trp, homoPhe and homologs of Met are increasingly well understood, while GSL biosynthesis from mono- and dihomoIle is poorly understood. Overall, interpretation of known diversity suggests that evolution of GSL biosynthesis often seems to recapitulate ancient biosynthesis. In contrast, unprecedented GSL biosynthetic innovation seems to be rare.
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Affiliation(s)
- Niels Agerbirk
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark.
| | - Cecilie Cetti Hansen
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Christiane Kiefer
- Department of Biodiversity and Plant Systematics, Centre for Organismal Studies, Heidelberg University, 69120, Heidelberg, Germany
| | - Thure P Hauser
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Marian Ørgaard
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Conny Bruun Asmussen Lange
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Don Cipollini
- Department of Biological Sciences, Wright State University, 3640 Colonel Glenn Highway, Dayton, OH, 45435, USA
| | - Marcus A Koch
- Department of Biodiversity and Plant Systematics, Centre for Organismal Studies, Heidelberg University, 69120, Heidelberg, Germany
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