Biosynthetic 4,6-dehydratase gene deletion: isolation of a glucosylated jadomycin natural product provides insight into the substrate specificity of glycosyltransferase JadS.

Deletion of the biosynthetic 4,6-dehydratase gene, jadT, present in the angucycline jadomycin dideoxysugar biosynthetic pathway, led to the isolation of a novel C12 glucosylated jadomycin. JadS was identified as the catalyst responsible for glucosylation due to a loss of production of the glucosylated natural product in a ΔjadSΔjadT deletion strain. This study demonstrates that a 2,6-dideoxy-l-sugar glycosyltransferase is able to transfer d-glucose, exemplifying remarkable substrate tolerance.

Kinetic evaluation of glucose 1-phosphate analogues with a thymidylyltransferase using a continuous coupled enzyme assay.

Cps2L, a thymidylytransferase, is the first enzyme in Streptococcus pneumoniae L-rhamnose biosynthesis and an antibacterial target. We herein report the evaluation of six sugar phosphate analogues selected to further probe Cps2L substrate tolerance. A modified continuous spectrophotometric assay was employed for facile detection of pyrophosphate (PPi) released from nucleotidylyltransfase-catalysed condensation of sugar 1-phosphates and nucleoside triphosphates to produce sugar nucleotides. Additionally, experiments using waterLOGSY NMR spectroscopy were investigated as a complimentary method to evaluate binding affinity to Cps2L.