The membrane-bound O-acyltransferase Ale1 transfers an acyl moiety to newly synthesized 2-alkyl-sn-glycero-3-phosphocholine in yeast.

To elucidate the mechanism of acyl chain remodeling at the sn-1 position of phosphatidylcholine (PC), we investigated acyl chain introduction using a newly synthesized 1-hydroxy-2-hexadecyl-sn-glycero-3-phosphocholine (HHPC) in Saccharomyces cerevisiae. HHPC is incorporated into yeast cells and converted to a PC species containing acyl residues of 16 or 18 carbons. The efficiency of palmitoleic acid introduction to HHPCin vitro is lower in the reaction with the extract from the deletion mutant of ALE1, which encodes a membrane-bound O-acyltransferase, than in that with extracts from the wild-type strain. In addition, deletion of ALE1 causes reductions in the molecular species containing acyl residues in HHPC. These results reveal that ALE1 is involved in acyl chain transfer to the sn-1 position of HHPC in yeast.

Development of highly potent D-glucosamine-based chiral fluorescent labeling reagents and a microwave-assisted beta-selective glycosidation of a methyl glycoside reagent.

We synthesized new chiral fluorescence labeling reagents having a 2,3-anthracenedicarboximide group from D-glucosamine, and it was possible to introduce target alcohols at the anomeric positions of the reagents with beta-selectivity by glycosidations. Especially, it was possible to use methyl glycoside reagent as a glycosyl donor with a Lewis acid and microwave irradiation, and it gave selectively beta-glycoside while the reaction without microwave irradiation gave alpha- and beta-mixed glycosides. Those reagents showed very high chiral discrimination ability, and they made it possible to separate the eight stereoisomers of 4,8,12,16-tetramethylheptadecanol by HPLC after derivatizations.