70082-70-1Relevant academic research and scientific papers
Synthesis of L-threo- and L-erythro-amino acids: novel probes for conformational analysis of peptide side chains
Oba, Makoto,Ueno, Ryuichi,Fukuoka, Mika,Kainosho, Masatsune,Nishiyama, Kozaburo
, p. 1603 - 1610 (2007/10/02)
An efficient and convenient route for the preparation of L-threo- and L-erythro-amino acids 5 as probes for the conformational analysis of peptide side chains by NMR spectroscopy is described.Stereoselective incorporation of deuterium into the α,β-positions of amino acid 5 was accomplished by catalytic deuteration of dehydroamino acid derivatives 1 and 2 followed by a combination of enzymic optical resilution and the racemization at the 2-position.Using these doubly labelled amino acids, it was possible to obtain vicinal coupling constants between carbonyl carbon and prochiral β-protons, J(13C-1Hβ1) and J(13C1-1Hβ2), through 13C NMR spectroscopy alone.We also demonstrate the determination of the fractional populations of rotamers in respect of the Cα-Cβ bond of the amino acids using the measured coupling constants.
L-Tryptophan 2',3'-oxidase from Chromobacterium violaceum catalyzes the synthesis of &α,&β-dehydrotryptophanyl residues in peptides and proteins: A tool for chemical modification and labelling of peptides and proteins
Genet, R,Denoyelle, C,Menez, A
, p. 848 - 850 (2007/10/02)
In 1975, Davis et al. reported the capacity of Chromobacterium violaceum (ATCC 12472) to transform Cbz-L-tryptophan into its α,β-dehydro derivative.However, reaction specificity and structural features of the putative enzyme which is responsible for this activity were not determined.We have isolated from this strain an enzyme designated L-tryptophan 2',3'-oxidase, which catalyzes the formation of a double bond at the Cα-Cβ position of tryptophan residues.Using a variety of tryptophan derivatives, we have demonstrated thatthe enzyme is highly specific for unsubstituted indole containing compounds and showed that the enzyme not only acts on isolated tryptophanyl side-chains but is also capable of dehydrogenating tryptophan residues in peptides and proteins.
