Distinct Metabolites for Photoreactive l-Phenylalanine Derivatives in Klebsiella sp. CK6 Isolated from Rhizosphere of a Wild Dipterocarp Sapling

Abstract

Photoaffinity labeling is a reliable analytical method for biological functional analysis. Three major photophores--aryl azide, benzophenone and trifluoromethyldiazirine--are utilized in analysis. Photophore-bearing L-phenylalanine derivatives, which are used for biological functional analysis, were inoculated into a Klebsiella sp. isolated from the rhizosphere of a wild dipterocarp sapling in Central Kalimantan, Indonesia, under nitrogen-limiting conditions. The proportions of metabolites were quite distinct for each photophore. These results indicated that photophores affected substrate recognition in rhizobacterial metabolic pathways, and differential photoaffinity labeling could be achieved using different photophore-containing L-phenylalanine derivatives.

Hydrogen/deuterium exchange of cross-linkable α-amino acid derivatives in deuterated triflic acid

“…Photoreactive L-phenylalanine derivatives were synthesized by methods described in a previous study. 24) General procedures for H/D exchange with TfOD. Cross-linkable aromatic α-amino acid derivatives (0.25 mM) were dissolved in TfOD (0.9 mL, 10 mM) at a specific temperature.…”

Synthesis of Cross-linkable 2,5-Diketopiperazine Derivatives

“…Photophore containing derivatives, L-Phe(4-N 3 ) 9 [19], was converted corresponding methyl ester hydrochloride 10 with thionyl chroide in methanol at room temperature. Compound 10 was subjected to peptide coupling with BocGly 3 or Boc-L-Tyr 6 in the presence DCC in acetonitrile and DMF.…”

Synthesis and Explosion Hazards of 4-Azido-l-phenylalanine

“…Three approaches have been reported for the synthesis of 4 : (1) azidodediazoniation of the corresponding phenyldiazonium species, (2) a diazotransfer reaction performed with imidazole-1-sulfonyl azide acting on a protected 4-aminophenylalanine derivative, and (3) an Ullman-type coupling of a protected 4-iodo- l -phenylalanine derivative directly to an azide anion (Figure ). The azidodediazoniation and diazotransfer approaches are not appropriate for multigram-scale preparations owing to the well-documented explosion hazards of these transformations .…”