A Linalool Synthase from Taiwanese Perilla citriodora

Abstract

A linalool synthase gene was isolated from a pure strain of Taiwanese Perilla citriodora, which has a different essential oil composition from that of other wild species of perilla and only trace amount of linalool was detected from the plant. The amino acid sequence of the linalool synthase gene was very similar to that of previously reported Japanese wild species. The isolated linalool synthase had a Km value of about 33 μM for geranyl diphosphate (GDP), which is considerably larger than that of limonene synthase from the same plant and of other known linalool synthases. Semi-quantitative PCR analysis of the linalool and limonene synthases also indicated the gene expression of linalool synthase was lower than that of limonene synthase. It was proposed that the low gene expression level and the large Km value resulted in the trace amount of linalool in the plants.