Journal: Nature Communications

Article Title: Enzymatic twists evolved stereo-divergent alkaloids in the Solanaceae family

doi: 10.1038/s41467-025-59290-4

Figure Lengend Snippet: a Phylogenetic tree of genus Solanum with chirality of C25 stereocenter marked in purple, red, and purple-red stripes denoting species accumulating 25 R , 25 S, or both stereoisomers. b Chemical structures of aglycones most frequently found in the genus Solanum —configurations at C25 are marked either with purple (25 R ) or red (25 S ) dots. c Total Ion Chromatograms (TICs) of tomato leaf and eggplant seed extracts. Most abundant SGAs and saponins are annotated. d Extracted Ion Chromatograms (EICs) for α -tomatine (EIC 1034.5530), dehydrotomatine (EIC 1032.5537), solamargine (EIC 868.5053), and solasonine (EIC 884.5002). Metabolites with different chirality at C25 are appropriately annotated either 25 R or 25 S . Images of tomato, potato, and eggplant are from BioRender.

Article Snippet: We found that the “C25 R- low” population, producing mostly 25S α -tomatine, consisted of accessions collected from eastern and the central islands (i.e., San Cristóbal, Santa Fé, and Santa Cruz), while the “C25 R- medium” and “C25 R- high” populations, possessing higher levels of 25R α -tomatine, contained accessions exclusively from the western islands (i.e., Fernandina and Isabela; Fig. ).

Techniques:

Journal: Nature Communications

Article Title: Enzymatic twists evolved stereo-divergent alkaloids in the Solanaceae family

doi: 10.1038/s41467-025-59290-4

Figure Lengend Snippet: a LC-MS analysis of SGA ( α -tomatine) in either tomato hairy roots with knocked out SlGAME8 ( SlGAME8-ko ), or expressing the eggplant SmGAME8 in the tomato SlGAME8-ko background. Hairy roots expressing GFP only were used as a control. b LC-MS analysis of aglycones (tomatidine and soladulcidine) in tomato hairy roots with knocked out SlGAME8 ( SlGAME8-ko ), or expressing SmGAME8 in SlGAME8-ko background. c , d LC-MS analysis of intermediates cholesterol-GlcA ( c ) and 22S-hydroxycholesterol-GlcA ( d ) in the same hairy root lines. Identity of metabolites was assigned based on accurate mass and our previous studies . e Percentage of 25 R α -tomatine in control and SmGAME8 expressing tomato hairy roots ( n = 14 of independent replicates for each genotype, P = 2.32756E-45). f Extracted ion chromatograms (EICs) showing accumulation of the steroidal saponin uttroside B and 25- epi -uttroside B in WT and SlGAME8 expressing Solanum nigrum leaves. g Percentage of 25- epi -uttroside B in WT and SlGAME8 expressing S. nigrum ( n = 5 of independent replicates for each genotype, P = 1.11608E-07). Asterisks indicate statistically significant differences as compared to control or WT determined by two-sided Student’s t -test. Box plots show all data points, center line represents median value, bounds correspond to upper and lower quartile, and whiskers represent min and max values.

Article Snippet: We found that the “C25 R- low” population, producing mostly 25S α -tomatine, consisted of accessions collected from eastern and the central islands (i.e., San Cristóbal, Santa Fé, and Santa Cruz), while the “C25 R- medium” and “C25 R- high” populations, possessing higher levels of 25R α -tomatine, contained accessions exclusively from the western islands (i.e., Fernandina and Isabela; Fig. ).

Techniques: Liquid Chromatography with Mass Spectroscopy, Expressing, Control

Journal: Nature Communications

Article Title: Enzymatic twists evolved stereo-divergent alkaloids in the Solanaceae family

doi: 10.1038/s41467-025-59290-4

Figure Lengend Snippet: a Extracted ion chromatograms (EICs) showing accumulation of α -tomatine C25 isomers in domesticated and wild tomato species. Arrows indicate 25 S and 25 R isomer. b LC-MS analysis of SGA aglycones (tomatidine and soladulcidine) in S. lycopersicum , S. pennellii , and S. cheesmaniae leaves. c Production of SGA aglycone isomers (tomatidenol and solasodine) by S. pennellii GAME8-1 or GAME8-2, or S. cheesmaniae GAME8 in N. benthamiana leaves analyzed by LC-MS. As controls we used GAME8 genes from tomato and eggplant. d Multiple sequence alignment of active sites’ amino acid sequences from GAME8 enzymes with 25 S (red) or 25 R (purple) or mixed stereospecificity. SgalGAME8 corresponds to GAME8 enzyme from Solanum galapagense (see Fig. for more details). Differential amino acids are highlighted in yellow and pale blue. e qPCR expression analysis of SpGAME8 genes in S. pennellii leaf ( n = 8 of independent measurements for each gene, P = 4.70744E-15). f Analysis of relative concentration of 25 S and 25 R α -tomatine isomers in S. pennellii leaf ( n = 7, independent measurement, P = 2.02513E-08). Comparing ( e , f ), we can see that levels of gene expression correlate with metabolite content in the same tissue. g Map of northwestern part of South America showing origins of wilds tomato accessions used in this study (Fig. 6a); the blue star on the map represents Lima, the capital of Peru. h EICs showing accumulation of α -tomatine C25 isomers in selected S. pennellii introgression lines (ILs) and in parental species. Arrows indicate 25 S and 25 R isomer. Asterisks indicate statistically significant differences determined by two-sided Student’s t -test (*** − P < 0.001). Box plots show all data points, center line represents median value, bounds correspond to upper and lower quartile, and whiskers represent min and max values.

Article Snippet: We found that the “C25 R- low” population, producing mostly 25S α -tomatine, consisted of accessions collected from eastern and the central islands (i.e., San Cristóbal, Santa Fé, and Santa Cruz), while the “C25 R- medium” and “C25 R- high” populations, possessing higher levels of 25R α -tomatine, contained accessions exclusively from the western islands (i.e., Fernandina and Isabela; Fig. ).

Techniques: Liquid Chromatography with Mass Spectroscopy, Sequencing, Expressing, Concentration Assay, Gene Expression

Journal: Nature Communications

Article Title: Enzymatic twists evolved stereo-divergent alkaloids in the Solanaceae family

doi: 10.1038/s41467-025-59290-4

Figure Lengend Snippet: a Extracted ion chromatograms (EICs) showing accumulation of α -tomatine C25 isomers in selected accessions (LA0746, LA1402, and LA1412) of S. cheesmanie originating from different islands. Red, yellow, and purple annotations correspond do accessions accumulating 7%, 20%, or 40% of the 25 R isomer, respectively. b Relative amount of 25 R α -tomatine isomer (center lines and whiskers correspond to mean values and SD, respectively) in 35 accessions of S. cheesmaniae and 21 accessions of S. galapagense . Red, yellow, and purple triangles and circles correspond do accessions with different amounts of the 25 R isomer. c Map of Galápagos archipelago. Red triangles mark locations of S. galapagense accessions. Red, yellow, and purple disks indicate locations of S. cheesmaniae accessions accumulating 7%, 20%, and 45% of 25 R α -tomatine, respectively. Different hues of blue represent age of the islands. Increasing color depth indicates older age of the island ( My – million years). Adapted from Štefka . d Phylogenetic analysis and multiple sequence alignment of active sites’ amino acid sequences of selected GAME8 enzymes from multiple accessions of S. cheesmaniae . Red, yellow, and purple indicate percentage of 25R α -tomatine accumulated and the origin of analyzed accessions. An arrow indicates the evolutionary trajectory of S. cheesmaniae GAME8 . e EICs illustrating in planta production (i.e., by transient expression in N. benthamiana ) of solasodine (25 R ) and tomatidenol (25 S ) by GAME8 enzymes from selected accessions of S. cheesmaniae . Scatter plots represent mean value with SD, all data points are shown.

Article Snippet: We found that the “C25 R- low” population, producing mostly 25S α -tomatine, consisted of accessions collected from eastern and the central islands (i.e., San Cristóbal, Santa Fé, and Santa Cruz), while the “C25 R- medium” and “C25 R- high” populations, possessing higher levels of 25R α -tomatine, contained accessions exclusively from the western islands (i.e., Fernandina and Isabela; Fig. ).

Techniques: Sequencing, Expressing