85808-34-0Relevant academic research and scientific papers
Preparation of cross-linked enzyme aggregates of l-aminoacylase via co-aggregation with polyethyleneimine
Vaidya, Bhalchandra K.,Kuwar, Suyog S.,Golegaonkar, Sandeep B.,Nene, Sanjay N.
, p. 184 - 191 (2012)
l-Aminoacylase from Aspergillus melleus was co-aggregated with polyethyleneimine and subsequently cross-linked with glutaraldehyde to obtain aminoacylase-polyethyleneimine cross-linked enzyme aggregates (termed as AP-CLEA). Under the optimum conditions, AP-CLEA expressed 74.9% activity recovery and 81.2% aggregation yield. The said method of co-aggregation and cross-linking significantly improved the catalytic stability of l-aminoacylase with respect to temperature and storage. AP-CLEA were employed for enantioselective synthesis of three unnatural amino acids (namely: phenylglycine, homophenylalanine and 2-naphthylalanine) via chiral resolution of their ester-, amide- and N-acetyl derivatives. The enantioselectivity of AP-CLEA was the highest for hydrolysis of amino acid amides; was moderate for hydrolysis of N-acetyl amino acids and was the least for hydrolysis of amino acid esters. Furthermore, AP-CLEA were found to retain more than 92% of the initial activity after five consecutive batches of (RS)-homophenylalanine hydrolysis suggesting an adequate operational stability of the biocatalyst.
Enzymatic synthesis of chiral phenylalanine derivatives by a dynamic kinetic resolution of corresponding amide and nitrile substrates with a multi-enzyme system
Yasukawa, Kazuyuki,Asano, Yasuhisa
supporting information, p. 3327 - 3332 (2013/01/15)
Mutant α-amino-ε-caprolactam (ACL) racemase (L19V/L78T) from Achromobacter obae with improved substrate specificity toward phenylalaninamide was obtained by directed evolution. The mutant ACL racemase and thermostable mutant D-amino acid amidase (DaaA) from Ochrobactrum anthropi SV3 co-expressed in Escherichia coli (pACLmut/pDBFB40) were utilized for synthesis of (R)-phenylalanine and non-natural (R)-phenylalanine derivatives (4-OH, 4-F, 3-F, and 2-F-Phe) by dynamic kinetic resolution (DKR). Recombinant E. coli with DaaA and mutant ACL racemase genes catalyzed the synthesis of (R)-phenylalanine with 84% yield and 99% ee from (RS)-phenylalaninamide (400 mM) in 22 h. (R)-Tyrosine and 4-fluoro-(R)-phenylalanine were also efficiently synthesized from the corresponding amide compounds. We also co-expresed two genes encoding mutant ACL racemase and L-amino acid amidase from Brevundimonas diminuta in E. coli and performed the efficient production of various (S)-phenylalanine derivatives. Moreover, 2-aminophenylpropionitrile was converted to (R)-phenylalanine by DKR using a combination of the non-stereoselective nitrile hydratase from recombinamt E. coli and mutant ACL racemase and DaaA from E. coli encoding mutant ACL racemase and DaaA genes. Copyright
Total synthesis of amiclenomycin, an inhibitor of biotin biosynthesis.
Mann, Stephane,Carillon, Sophie,Breyne, Olivier,Marquet, Andree
, p. 439 - 450 (2007/10/03)
We describe the first synthesis of amiclenomycin, a natural product that has been found to inhibit biotin biosynthesis and, as a consequence, to exhibit antibiotic properties. Structure 1, with a trans relationship between the ring substituents. had previously been proposed for amiclenomycin on the basis of its 1H NMR spectrum. We have prepared the trans and cis isomers 1 and 2 by unequivocal routes and we conclude that the natural product is in fact the cis isomer 2. The properly substituted cyclohexadienyl rings were constructed first. A cycloaddition reaction between 1,2-di(phenylsulfonyl)ethylene and the N-allyloxycarbonyl diene 13, followed by reductive elimination of the phenylsulfinyl groups, gave the cis isomer 15. To obtain the trans isomer, the O-trimethylsilyl diene was used to give the cis hydroxylated Diels-Alder adduct 33, which was transformed into the corresponding trans amino derivative by means of a Mitsunobu reaction. The L-alpha-amino acid functionality was introduced by means of a Strecker reaction on the aldehydes 16 and 42, followed by enzymatic hydrolysis with immobilised pronase.
Enantioselective enzyme catalysed ammoniolysis of amino acid derivatives. Effect of temperature
Lopez-Serrano, Paloma,Wegman, Margreth A.,Van Rantwijk, Fred,Sheldon, Roger A.
, p. 235 - 240 (2007/10/03)
The lipases from Candida antarctica (B type), Thermomyces lanuginosus and Pseudomonas alcaligenes catalysed the enantioselective ammoniolysis of free amino acid esters. In the ammoniolysis of phenylalanine methyl ester catalysed by T. lanuginosus lipase a
Bifunctional Chelating Agents. Part 1. 1-(p-Aminophenethyl)ethylenediaminetetra-acetic Acid
Altman, Janina,Shoef, Nurit,Wilchek, Meir,Warshawsky, Abraham
, p. 365 - 368 (2007/10/02)
The synthesis of a new bifunctional analogue of ethylenediaminetetra-acetic acid (EDTA), 1-(p-aminophenethyl)ethylenediaminetetra-acetic acid (13), from the amide of 2-amino-4-phenylbutyric acid (8) by reduction with diborane and acetylation to give compo
