Characterization of a Cytosolic Acyl-Activating Enzyme Catalyzing the Formation of 4-Methylvaleryl-CoA for Pogostone Biosynthesis in Pogostemon Cablin. (13th July 2021)

• Record Type: Journal Article
• Authors: Chen, Jing; Liu, Lang; Wang, Ying; Li, Zhengguo; Wang, Guodong; Kraus, George A; Pichersky, Eran; Xu, Haiyang
• Is Part Of: Plant & cell physiology. Volume 62:Number 10(2021)
• Page Start: 1556
• Page End: 1571
• Publication Date: 2021-07-13
• Subjects: 4-Methylvaleric acid -- 4-Methylvaleryl-CoA -- Acyl-activating enzyme -- Branched-chain fatty acid -- Pogostemon cablin -- Pogostone; Plant physiology -- Periodicals; Microbiology -- Periodicals; Cytology -- Periodicals; Cell Physiology -- Periodicals; Plant Physiological Phenomena -- Periodicals; Cytology; Microbiology; Plant physiology; Periodicals; 571.205
• DOI: 10.1093/pcp/pcab111
• Languages: English
• ISSNs: 0032-0781

Abstract

Abstract: Pogostone, a compound with various pharmaceutical activities, is a major constituent of the essential oil preparation called Pogostemonis Herba, which is obtained from the plant Pogostemon cablin . The biosynthesis of pogostone has not been elucidated, but 4-methylvaleryl-CoA (4MVCoA) is a likely precursor. We analyzed the distribution of pogostone in P. cablin using gas chromatography-mass spectrometry (GC-MS) and found that pogostone accumulates at high levels in the main stems and leaves of young plants. A search for the acyl-activating enzyme (AAE) that catalyzes the formation of 4MVCoA from 4-methylvaleric acid was launched, using an RNAseq-based approach to identify 31 unigenes encoding putative AAEs including the PcAAE2, the transcript profile of which shows a strong positive correlation with the distribution pattern of pogostone. The protein encoded by PcAAE2 was biochemically characterized in vitro and shown to catalyze the formation of 4MVCoA from 4-methylvaleric acid. Phylogenetic analysis showed that Pc AAE2 is closely related to other AAE proteins in P. cablin and other species that are localized to the peroxisomes. However, Pc AAE2 lacks a peroxisome targeting sequence 1 (PTS1) and is localized in the cytosol.