Isolation and Characterization of Some Genes Involved in Essential Oil Synthesis in Endemic Sütçüler Thyme (Origanum minutiflorum)

Origanum minutiflorum, is an endemic species found in the Sütçüler district of Isparta province, Turkey. This study aimed to isolate and characterize the 1-deoxy-D-xylulose-5-phosphate reductoisomerase (OmDXR) and terpene synthase 1 (OmTPS-1) genes, which play roles in essential oil biosynthesis in O. minutiflorum. For this purpose, total RNA was isolated from thyme leaves, and the sequence information of the target genes was obtained using gene-specific primers. The sequences were compared with those from other species in the NCBI database using BLAST programs. The nucleotide sequences were translated into protein sequences using ExPASy Tools, the three-dimensional structures of the encoded proteins were constructed with 3D SWISS-MODEL, and phylogenetic relationships of nucleotide and protein sequences were analyzed using the MEGA X version 11 software package. The results showed that the full-length cDNA nucleotide sequence of the OmDXR gene is 1,700 base pairs (bp), and its nucleotide sequence displayed 74.22%-81.07% similarity to nucleotide sequences from other species in previous studies, while the protein sequence showed 70.92%-72.95% similarity. The full-length cDNA nucleotide sequence of the OmTPS-1 gene was determined to be 1.836 bp, and its nucleotide sequence exhibited 75.99%-89.58% similarity to nucleotide sequences from other species, while the protein sequence showed 51.66%-69.88% similarity. This study represents the first molecular-based research on the O. minutiflorum species. Therefore, it will provide a valuable resource for future studies.