Access to Any Site Directed Stable Isotope (2H, 13C, 15N, 17O and 18O) in Genetically Encoded Amino Acids

Abstract

Proteins and peptides play a preeminent role in the processes of living cells. The only way to study structure-function relationships of a protein at the atomic level without any perturbation is by using non-invasive isotope sensitive techniques with site-directed stable isotope incorporation at a predetermined amino acid residue in the protein chain. The method can be extended to study the protein chain tagged with stable isotope enriched amino acid residues at any position or combinations of positions in the system. In order to access these studies synthetic methods to prepare any possible isotopologue and isotopomer of the 22 genetically encoded amino acids have to be available. In this paper the synthetic schemes and the stable isotope enriched building blocks that are available via commercially available stable isotope enriched starting materials are described.

Segmental and site-specific isotope labelling strategies for structural analysis of posttranslationally modified proteins

“…However, high costs and limited availability of building blocks together with size limitations of synthetic peptides restrict its broader use in the field of isotope labelling -a drawback that might be overcome by the development of cost-effective methods to generate isotope labelled amino acids suitably protected for solid phase peptide synthesis. 62,166 EPL circumvents these challenges by accessing isotope labelled protein segments using recombinant expression, which also removes size limitations. In combination with SPPS, posttranslational modifications can be incorporated into segmentally labelled proteins.…”

“…Furthermore, the total chemical synthesis of proteins for spectroscopic applications suffers from restrictions in length of the accessible proteins and prohibitively expensive isotope-labelled amino acid building blocks. 62 Therefore, SPPS is more widely used to incorporate site-specific PTMs than site-specific isotope labels.…”

Using Hydrogen Stable Isotope Ratios to Trace the Geographic Origin of the Population ofBactrocera dorsalis(Diptera: Tephritidae) Trapped in Northern China

“…The δ 2 H stable isotope also is transmitted within the food web from low trophic level species to high trophic level species at a constant fractional distillation (Dawadi & Lugtenburg 2013;Górka et al 2017). However, the mechanism of fractionation of the δ 2 H stable isotope in the precipitation-host-fruit fly relationship is not clear (Bortolotti et al 2013), and the transmitting mechanism of the δ 2 H stable isotope in the food web of the ecosystem is an unexplored field for future work (Weber et al 2017).…”

[13C+D] Double Labeling with Calcium Carbide: Incorporation of Two Labels in One Step

“…A vast majority of substrates can be deuterated according to well‐known procedures, [9] based on protium‐deuterium exchange, [10] hydrogenation with D 2 gas, [11] or multi‐step construction of molecules [12] starting from commercially available D‐sources. When the level of deuterium is increased from the natural abundance value of ≈0.02% to >90%, the compound can be considered as deuterated.…”

“…[7] In medicine, D-labeled drugs can be considered as more efficient and more bioavailable biologically active compounds with a prolonged effect due to stronger carbon-deuterium bond. [8] A vast majority of substrates can be deuterated according to well-known procedures, [9] based on protium-deuterium exchange, [10] hydrogenation with D 2 gas, [11] or multi-step construction of molecules [12] starting from commercially available D-sources. When the level of deuterium is increased from the natural abundance value of � 0.02% to > 90%, the compound can be considered as deuterated.…”