02358nas a2200253   4500008004100000245011500041210006900156260000800225300000900233490000700242520149500249100002701744700002301771700001801794700002001812700002001832700002601852700001601878700002001894700002401914700002001938700001901958856012701977       2023                        eng d00aBAHD-type acyltransferase concludes the biosynthetic pathway of non-bitter glycoalkaloids in ripe tomato fruit0 aBAHDtype acyltransferase concludes the biosynthetic pathway of n  cJUL  a45400 v143 a<p>
	During tomato fruit ripening, bitter and toxic steroidal glycoalkaloids (SGAs) are converted to nonbitter and less toxic forms, but proposed acylating enzyme in pathway remain unknown. Here, authors report BAHD-type acyltransferase that catalyze acylation step in biosynthesis of non-bitter SGAs in tomato. Tomato is the highest value fruit and vegetable crop worldwide, yet produces &amp; alpha;-tomatine, a renowned toxic and bitter-tasting anti-nutritional steroidal glycoalkaloid (SGA) involved in plant defense. A suite of modifications during tomato fruit maturation and ripening converts &amp; alpha;-tomatine to the non-bitter and less toxic Esculeoside A. This important metabolic shift prevents bitterness and toxicity in ripe tomato fruit. While the enzymes catalyzing glycosylation and hydroxylation reactions in the Esculeoside A pathway have been resolved, the proposed acetylating step remains, to date, elusive. Here, we discovered that GAME36 (GLYCOALKALOID METABOLISM36), a BAHD-type acyltransferase catalyzes SGA-acetylation in cultivated and wild tomatoes. This finding completes the elucidation of the core Esculeoside A biosynthetic pathway in ripe tomato, allowing reconstitution of Esculeoside A production in heterologous microbial and plant hosts. The involvement of GAME36 in bitter SGA detoxification pathway points to a key role in the evolution of sweet-tasting tomato as well as in the domestication and breeding of modern cultivated tomato fruit.</p>
1 aSonawane, Prashant, D.1 aGharat, Sachin, A.1 aJozwiak, Adam1 aBarbole, Ranjit1 aHeinicke, Sarah1 aAlmekias-Siegl, Efrat1 aMeir, Sagit1 aRogachev, Ilana1 aO'Connor, Sarah, E.1 aGiri, Ashok, P.1 aAharoni, Asaph  uhttps://library.ncl.res.in/content/bahd-type-acyltransferase-concludes-biosynthetic-pathway-non-bitter-glycoalkaloids-ripe