DBG · Promoting young researchers

Mareike Busche (Bielefeld University)

Mareike Busche's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Bielefeld University in the year 2018.

Title of awarded thesis

"Functional characterisation of two flavonol synthases and an anthocyanidin synthase from Musa acuminata"

This work contributes to understanding of flavonol and anthocyanidin synthesis in Musa acuminata (banana) and provides a basis for further research towards increased flavonoid production through the analysis of two involved enzymes.

Flavonoids are plant secondary metabolites with many beneficial effects. They protect plants against UV-B radiation, provide signals to symbionts and promote human health. Based on close sequence similarity to known flavonol- and anthocyanidin synthases, coding sequences of two predicted flavonol synthases and an anthocyanidin synthase from Musa acuminata were amplified, sequenced and cloned into destination vectors.

Enzymatic properties of MaFLS1a and MaFLS3a were analysed by expression and an enzymatic assay in Escherichia coli. MaFLS1a, in contrast to MaFLS3a, was able to convert dihydrokaempferol to kaempferol. In Arabidopsis thaliana both flavonol synthases were capable of complementing the flavonol deficiency of ldox fls1-2 plants. ldox fls1-2 plants complemented with the MaANS coding sequence showed high levels of anthocyanins and were therefore able to complement the anthocyanin deficiency.

___

Mareike Busche conducted this work at the Chair of Genetics & Genomics of Plants in the working group of Prof. Dr. Bernd Weisshaar in the working group of Dr. Ralf Stracke.


A) A banana plant. B) Accumulation of red pigments in the plant's leaves. Anthocyanins are very likely to contribute a major part of the red pigments.