634-97-9Relevant articles and documents
Identification and characterization of bifunctional proline racemase/hydroxyproline epimerase from archaea: Discrimination of substrates and molecular evolution
Watanabe, Seiya,Tanimoto, Yoshiaki,Nishiwaki, Hisashi,Watanabe, Yasuo
, (2015)
Proline racemase (ProR) is a member of the pyridoxal 5′-phosphate-independent racemase family, and is involved in the Stickland reaction (fermentation) in certain clostridia as well as the mechanisms underlying the escape of parasites fromhost immunity in eukaryotic Trypanosoma. Hydroxyproline epimerase (HypE), which is in the same protein family as ProR, catalyzes the first step of the trans-4-hydroxy-L-proline metabolism of bacteria. Their substrate specificities were previously considered to be very strict, in spite of similarities in their structures and catalytic mechanisms, and no racemase/epimerase fromthe ProR superfamily has been found in archaea.We here characterized the ProR-like protein (OCC-00372) from the hyperthermophilic archaeon, Thermococcus litoralis (TlProR). This protein could reversibly catalyze not only the racemization of proline, but also the epimerization of 4-hydroxyproline and 3-hydroxyproline with similar kinetic constants. Among the four (putative) ligand binding sites, one amino acid substitution was detected between TlProR (tryptophan at the position of 241) and natural ProR (phenylalanine). TheW241F mutant showed a significant preference for proline over hydroxyproline, suggesting that this (hydrophobic and bulky) tryptophan residue played an importance role in the recognition of hydroxyproline (more hydrophilic and bulky than proline), and substrate specificity for hydroxyproline was evolutionarily acquired separately between natural HypE and ProR. A phylogenetic analysis indicated that such unique broad substrate specificity was derived from an ancestral enzyme of this superfamily.
Isolation and characterization of antibiotic X-14547A, a novel monocarboxylic acid ionophore produced by Streptomyces antibioticus NRRL 8167
Westley,Evans Jr.,Sello,Troupe,Liu,Blount
, p. 100 - 107 (1979)
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Capon,R.J.,Faulkner,D.J.
, p. 1819 (1984)
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Conversion of pyrrole to pyrrole-2-carboxylate by cells of Bacillus megaterium in supercritical CO2
Matsuda,Ohashi,Harada,Yanagihara,Nagasawa,Nakamura
, p. 2194 - 2195 (2001)
Pyrrole was converted to pyrrole-2-carboxylate in supercritical CO2 using cells of Bacillus megaterium PYR 2910, and the yield of the carboxylation reaction in supercritical CO2 was 12 times higher than that under atmospheric pressur
N,N-coordination Rh complex as well as synthesis method and application thereof
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Paragraph 0024; 0025; 0026, (2018/03/28)
The invention belongs to the technical field of synthesis of organic metal compounds and particularly relates to an N,N-coordination Rh complex as well as a synthesis method and an application thereof. Firstly, a ligand is synthesized from methyl 1H-pyrrole-2-carboxylate as an initial raw material and further reacts with Rh(COD)2Cl, and a metal complex with Rh as a central atom is obtained. The synthesis method is simple, the complex as a catalyst can be used for catalyzing a series of reductive amination reactions of derivatives of acetophenone and aniline, and the product yield is good and is 90% or above.
Vanadium(v) oxoanions in basic water solution: A simple oxidative system for the one pot selective conversion of l-proline to pyrroline-2-carboxylate
Biancalana, Lorenzo,Tuci, Giada,Piccinelli, Fabio,Marchetti, Fabio,Bortoluzzi, Marco,Pampaloni, Guido
, p. 15059 - 15069 (2017/11/14)
The unprecedented, direct chemical oxidation of l-proline to pyrroline-2-carboxylate was achieved in water (pH 9-10) by means of NH4VO3/NH3 or V2O5/MOH (K = Na, K), and the anion was fully characterized as ammonium or alkaline metal salts. Quantitative yield and higher atom economy performance were achieved with the latter system, the alkaline salts being more stable than the ammonium one. Different mixed valence V(iv)/V(v) compounds precipitated from the reaction mixtures depending on the nature of the employed base. A possible reaction mechanism is proposed according to DFT calculations. The analogous reaction of trans-4-hydroxy-l-proline with NH4VO3/NH3 afforded pyrrole-2-carboxylic acid in 81% yield, while sarcosine underwent prevalent decomposition under similar experimental conditions. Instead, no reaction was observed with primary (glycine, l-alanine, l-phenylalanine) and tertiary α-amino acids (N,N-dimethyl-l-phenylalanine, N,N-dimethylglycine).
