The role of 2-methyl-6-phytylbenzoquinone methyltransferase in determining tocopherol composition in Synechocystis sp. PCC6803.

Abstract

A putative 2-methyl-6-phytylbenzoquinone (MPBQ) methyltransferase gene, SLL0418, was identified from the Synechocystis PCC6803 genome based on its homology to previously characterized gamma-tocopherol methyltransferases. Genetic and biochemical evidence confirmed open reading frame (ORF) SLL0418 encodes a MPBQ methyltransferase. An SLL0418 partial knockout mutant accumulated beta-tocopherol with no effect in the overall tocopherol content of the cell. In vitro assays of the SLL0418 gene expressed in Escherichia coli showed the enzyme efficiently catalyzes methylation of ring carbon 3 of MPBQ. In addition, the enzyme also catalyzes the methylation of ring carbon 3 of 2-methyl-6-solanylbenzoquinol in the terminal step of plastoquinone biosynthesis.

• Authors: David K Shintani, Zigang Cheng, Dean DellaPenna
• Journal: FEBS letters (FEBS Lett) Vol. 511 Issue 1-3 Pg. 1-5 (Jan 30 2002) ISSN: 0014-5793 [Print] England
• PMID: 11821038 (Publication Type: Journal Article)

Chemical References

• demethylphytylplastoquinone
• 2-methyl-6-phytylbenzoquinone methyltransferase
• Methyltransferases
• Plastoquinone
• Tocopherols

Topics

• Amino Acid Sequence
• Chromatography, High Pressure Liquid
• Cyanobacteria (chemistry, enzymology, genetics)
• Gas Chromatography-Mass Spectrometry
• Methylation
• Methyltransferases (chemistry, genetics, metabolism)
• Molecular Sequence Data
• Mutagenesis, Site-Directed
• Plastoquinone (analogs & derivatives, metabolism)
• Sequence Homology, Amino Acid
• Time Factors
• Tocopherols (analysis, chemistry, metabolism)