Document Detail

Production of the apoptotic cellular mediator 4-Methylthio-2-oxobutyric acid by using an enzymatic stirred tank reactor with in situ product removal.
MedLine Citation:
PMID:  18092800     Owner:  NLM     Status:  MEDLINE    
d-Amino acid oxidase (DAAO) was used to study the oxidative deamination of racemic mixtures of d,l-methionine in its soluble and immobilized forms and thus obtain the corresponding alpha-keto acid. The soluble enzyme form was obtained from a Trigonopsis variabilis CBS 4095 extract, free of l-amino acid oxidase, and was co-immobilized with a 200-fold excess of catalase to avoid the undesirable side reaction of H2O2 with the alpha-keto acid, which would otherwise render its corresponding decarboxylated acid, the 3-methylthiopropionic acid (MTPA). With this biocatalyst, quantitative conversion (>98%) of d-methionine into the alpha-keto acid 4-methylthio-2-oxobutyric acid (MTOB) and into MTPA was achieved using 5 mg.mL(-1) of biocatalyst at pH 8.0, 25 degrees C, and pure oxygen at 3 vvm. A stirred tank reactor with in situ product removal (STR-ISPR) was developed to avoid conversion of MTOB into MTPA. The reaction medium was re-circulated through a strong anion exchange column (Amberlite IRA-400). This resulted in the complete removal of MTOB from the reaction medium. After the reaction, the reaction products were eluted sequentially with water (l-methionine), 10 mM HCl (MTPA), and 0.5 M HCl (MTOB). After elution, MTOB was crystallized to its sodium salt.
Miguel García-García; Irene Martínez-Martínez; Alvaro Sánchez-Ferrer; Francisco García-Carmona
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2007-12-20
Journal Detail:
Title:  Biotechnology progress     Volume:  24     ISSN:  8756-7938     ISO Abbreviation:  Biotechnol. Prog.     Publication Date:    2008 Jan-Feb
Date Detail:
Created Date:  2008-02-01     Completed Date:  2008-06-13     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8506292     Medline TA:  Biotechnol Prog     Country:  United States    
Other Details:
Languages:  eng     Pagination:  187-91     Citation Subset:  IM    
Department of Biochemistry and Molecular Biology-A, Faculty of Biology, University of Murcia, Campus Espinardo, E-30071 Murcia, Spain.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Ascomycota / enzymology
D-Amino-Acid Oxidase / metabolism*
Magnetic Resonance Spectroscopy
Methionine / analogs & derivatives*,  chemistry,  metabolism
Molecular Structure
Reg. No./Substance:
583-92-6/2-keto-4-methylthiobutyric acid; 63-68-3/Methionine; EC Oxidase

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Limited use of Centritech Lab II Centrifuge in perfusion culture of rCHO cells for the production of...
Next Document:  Synthesis of epi-oxetin via a serine-derived 2-methyleneoxetane.