Feeding of (2S,3R)-[2,3-13C2]-2-methyl-3-hydroxypentanoyl NAC thioester (1a) to the recombinant organism Streptomyces coelicolor CH999/pCK7 harboring the complete set of eryA genes from Saccharopolyspora erythraea encoding the 6-deoxyerythronolide B synthase (DEBS) resulted in the formation of 6-deoxyerythronolide B (2a) labeled with 13C at C-12 and C-13, as evidenced by the appearance of a pai...

Methyl groups provide an important source of structural and dynamic information in NMR studies of proteins and their complexes. For this purpose sequence-specific assignments of methyl 1H and 13C resonances are required. In this paper we propose the use of 13C-detected 3D HN(CA)C and HMCMC experiments for assignment of methyl 1H and 13C resonances using a single selectively methyl protonated, p...

Content Synthetic scheme of phosphoramidite 9b ------------------------------------------------------------------S3 Figure S1 ------------------------------------------------------------------------------------------------------S4 Figure S2 ------------------------------------------------------------------------------------------------------S4 Figure S3 -----------------------------------------...

There are conflicting reports concerning the reliability of mass isotopomer distribution analysis (MIDA) for estimating the contribution of gluconeogenesis to total glucose production (f) during [13C]glycerol infusion. 1 We have evaluated substrate-induced effects on rate of appearance (Ra) of glycerol and glucose and f during [2-13C]glycerol infusion in vivo. Five groups of mice were fasted fo...

We have identified a new target for the chemopreventive dietary agent indole-3-carbinol (13C) in the antiapoptotic signaling pathway involving phosphatidylinositol 3'-kinase and protein kinase B (PKB)/Akt. 13C inhibited phosphorylation and activation of PKB in the tumor-derived breast cell line MDA MB468, but not in the immortalized breast line HBL100. We propose that this cell type-specific re...

Xyloglucan from the walls of Rosa cells that had been cultured on [12C]- or [13C]-glucose formed bands in caesium trifluoroacetate with mean buoyant densities of 1.575 or 1.616 g/ml respectively. Incubation of a mixture of [13C,3H]xyloglucan and [12C,1H]xyloglucan in the presence of xyloglucan endotransglycosylase (XET) activity caused the mean buoyant density of the radioactive material to dec...

13C NMR of isotopically enriched metabolites has been used to study the metabolism of Microbacterium ammoniaphilum, a bacterium which excretes large quantities of L-glutamic acid into the medium. Biosynthesis from 90% [1-13C]glucose results in relatively high specificity of the label, with [2,4-13C2]glutamate as the major product. The predominant biosynthetic pathway for synthesis of glutamate ...

A two-dimensional [31P] spin-echo-difference constant-time [13C, 1H]-HMQC experiment (2D [31P]-sedct-[13C, 1H]-HMQC) is introduced for measurements of 3J(C4'P) and 3J(H3'P) scalar couplings in large 13C-labeled nucleic acids and in DNA-protein complexes. This experiment makes use of the fact that 1H-13C multiple-quantum coherences in macromolecules relax more slowly than the corresponding 13C s...

A new magic-angle spinning NMR method for measuring internuclear distances between a 13C-labeled site and amide protons is described. The magnetization of the protons evolves under homonuclear decoupling and the recoupled 13C-1H dipolar interaction, which provides simple spin-pair REDOR curves if only one 13C-labeled site is present. The modulation of the amide proton HN is detected via short 1...