Systematic mining of fungal chimeric terpene synthases using an efficient precursor-providing yeast chassis
Rong Chen, Qidong Jia, Xin Mu, Ben Hu, Xiang Sun, Zixin Deng, Feng Chen, Guangkai Bian, Tiangang Liu
Abstract
Significance Chimeric terpene synthases, termed PTTSs, are a unique family of enzymes occurring only in fungi. Characterizing PTTSs is challenging due to the complex reactions they catalyze and the structural complexity of their products. Here, by devising an efficient precursor-providing yeast chassis and incorporating a high-throughput automated platform, we identified 34 active PTTSs, which was considerably more than the number of known functional PTTSs. This effective and rapid pipeline can be employed for the characterization of other PTTSs or related terpenoid biosynthetic enzymes. By systematically analyzing the presence/absence of PTTS genes together with phylogenetic analysis, the ancestral PTTS gene was inferred to have undergone duplication and functional divergence, which led to the development of two distinct cyclization mechanisms.