Cloning and characterization of a novel gene that encodes (S)-β-bisabolene synthase from ginger, Zingiber officinale

Ginger, Zingiber officinale Roscoe, contains a fragrant oil mainly composed of sesquiterpenes and monoterpenes. We isolated a cDNA that codes for a sesquiterpene synthase from young rhizomes of ginger, Z. officinale Roscoe, Japanese cultivar "Kintoki". The cDNA, designated ZoTps1, potentially encoded a protein that comprised 550 amino acid residues and exhibited 49-53% identity with those of the sesquiterpene synthases already isolated from the genus Zingiber. Recombinant Escherichia coli cells, in which ZoTps1 was coexpressed along with genes for d-mevalonate utilization, resulted in the production of a sesquiterpene (S)-beta-bisabolene exclusively with a d-mevalonolactone supplement. This result indicated that ZoTps1 was the (S)-beta-bisabolene synthase gene in ginger. ZoTPS1 was suggested to catalyze (S)-beta-bisabolene formation with the conversion of farnesyl diphosphate to nerolidyl diphosphate followed by the cyclization between position 1 and 6 carbons. The ZoTps1 transcript was detected in young rhizomes, but not in leaves, roots and mature rhizomes of the ginger "Kintoki".