Protein
Probable glycosyl transferase FCK3
Organism
Fusarium pseudograminearum (strain CS3096)
Function
Probable glycosyl transferase; part of the gene cluster that mediates the biosynthesis of cytokinins such as fusatin, fusatinic acids or 8-oxofusatin, known for their growth promoting and anti-senescence activities toward host plants (PubMed:28802024). FCK1 is a bifunctional enzyme that performs the first steps in the biosynthesis of Fusarium cytokinins (PubMed:28802024). It first condenses adenosine monophosphate (AMP) with dimethylallyl diphosphate (DMAPP) to yield isoprenyl adenosine monophosphate (PubMed:28802024). It then catalyzes the removal of the phosphoribose to produce isopentenylaldehyde (PubMed:28802024). The cytochrome P450 monooxygenase then converts isopentenylaldehyde to trans-zeatin (PubMed:28802024). A condensation step converts trans-zeatin to fusatin which is further modified to produce fusatinic acid (PubMed:28802024). The mechanism for oxidation of fusatin to fusatinic acid remains unknown (PubMed:28802024). 8-oxofusatin could be produced through several pathways, via direct oxygenation of fusatin, or via the 8-oxo-pentenyladenine intermediate which itself must arise from either the prenylation of 8-oxo-AMP by FCK1 and/or oxygenation of isopentenylaldehyde (PubMed:28802024). Both the FCK3 and FCK4 enzymes act downstream of the identified cytokinins to produce yet unidentified compounds (PubMed:28802024).
Sequence
MHFAIPLEYQSELEATEPVDVGTDEEIISSIEQYRPVTSEKNIWAFWDSGILSMPSWCKRNVIGWARICGADWTIRVLDMKPNSPNHVLKFIDRDMLPEAFLSGTMDGHHTGQHSADFIRGPLLHHYGGVSMDVGCLLIRHIDRICWDLLADPDSPYEIAVPVLYDQTIANHFIAARKNNIFIEKWHQLFLHLWNGRTHQQGISDSPLLGFIKDIRYDDATDFHWDWSVPVPQFLEYIAQVLCWQRLCLIRDTGDGFKSSEYWQRNVLCIDSLNEVWGGEKTLGFDGIGPRMYNLLTTRLDADPDSTAYKDAYKLVWRLLTRSSFQKVTRAKNLTYTPHLGTLWDQNEGKDCIPGSFGELLRYGPVHFRQKRENIEQLEASEPRTLIEKGLLEV