Characterization and application of a newly synthesized 2-deoxyribose-5-phosphate aldolase

Abstract

A codon-optimized 2-deoxyribose-5-phosphate aldolase (DERA) gene was newly synthesized and expressed in Escherichia coli to investigate its biochemical properties and applications in synthesis of statin intermediates. The expressed DERA was purified and characterized using 2-deoxyribose-5-phosphate as the substrate. The specific activity of recombinant DERA was 1.8 U/mg. The optimum pH and temperature for DERA activity were pH 7.0 and 35 C, respectively. The recombinant DERA was stable at pH 4.0-7.0 and at temperatures below 50 C. The enzyme activity was inhibited by 1 mM of Ni2+, Ba2+ and Fe2+. The apparent K m and V max values of purified enzyme for 2-deoxyribose-5-phosphate were 0.038 mM and 2.9 μmol min-1 mg-1, for 2-deoxyribose were 0.033 mM and 2.59 μmol min-1 mg-1, respectively, which revealed that the enzyme had similar catalytic efficiency towards phosphorylated and non-phosphorylated substrates. To synthesize statin intermediates, the bioconversion process for production of (3R, 5S)-6-chloro-2,4,6-trideoxyhexose from chloroacetaldehyde and acetaldehyde by the recombinant DERA was developed and a conversion of 94.4 % was achieved. This recombinant DERA could be a potential candidate for application in production of (3R, 5S)-6-chloro-2,4,6- trideoxyhexose. © 2012 Society for Industrial Microbiology and Biotechnology.