Synthesis of specially designed probes to broaden transketolase scope
Résumé
Efficient, biocompatible, stereospecific strategies were developed to prepare eight probes to assay transketolase (TK) variants with new substrate specificities. The structure of these probes combines a sugar moiety (D-threo or L-erythro ketose, or D-threo aldose) with the side chain of an amino acid (Ala, Leu, Val, Met, Thr) for in vivo detection of new TK activities using amino acid auxotrophs. To obtain D-threo ketose probes, biocatalysts, such as transketolase and fructose-6-phosphate aldolase Ala129Ser, were used whereas L-erythro ketoses and D-threo aldose probes were synthesized by the way of organocatalysis or Sharpless dihydroxylation as sustainable alternative key steps to biocatalysis.