Bioproduction of Glycolic Acid from Glycolonitrile with a New Bacterial Isolate of Alcaligenes sp. ECU0401

Abstract

Alcaligenes sp. ECU0401 has been isolated from soil samples with high nitrilase activity against glycolonitrile using the enrichment culture technique. The preferred carbon/nitrogen sources and metal ions were sodium acetate, a composite of peptone and yeast extract, and Cu(2+), respectively. Glycolic acid was obtained in a yield of 96.5% after 14 h of biotransformation from a total of 200 mM glycolonitrile in the mode of sequential addition during the cultivation of Alcaligenes sp. ECU0401 in a 5-L jar fermenter. Fifty micromolars of glycolonitrile could be hydrolyzed in a yield of 94.1% by resting cells after 36 h. The microbial nitrilase system could hydrolyze various nitriles with high activity, and no amidase activity and glycolic acid were observed in hydrolyzing glycolamide. It significantly exhibited high enantioselectivity in the hydrolysis of mandelonitrile and 2-chloromandelonitrile (>99.9% e.e.( p )). Efficient biocatalyst recycling was achieved as a result of immobilization in glutaraldehyde/polyethylenimine cross-linked carrageenan with immobilized cells exhibiting a biocatalyst productivity of 1,042.2 g glycolic acid per gram dry cell weight after 29 batch recycles.

Biosynthesis of Iminodiacetic Acid from Iminodiacetonitrile by Immobilized Recombinant <i>Escherichia coli</i> Harboring Nitrilase

“…Synthetic gels, on the contrary, have better mechanical properties, but mostly lower substrates and product diffusion coefficients [Leenen et al, 1996]. To date, there have been few reports about immobilization of nitrilase-producing bacteria employing chitosan , agar [Nigam et al, 2009], alginate [Chen et al, 2008;Shen et al, 2009], silica [Swartz et al, 2009], silica-carrageenan [Kabaivanova et al, 2011], glutaraldehyde [He et al, 2010], polyacrylamide and polyvinyl alcohol (PVA) [Vejvoda et al, 2006] as matrices. Though the gel beads of photo-crosslinked PVA and calcium-alginate mixtures have been applied successfully as carriers in a denitrification process [Dhake et al, 2011;Wang et al, 2007], there are no studies about using multiple polymers for immobilization of recombinant cells harboring nitrilase [Bryaskova et al, 2010].…”

Cloning and biochemical properties of a highly thermostable and enantioselective nitrilase from Alcaligenes sp. ECU0401 and its potential for (R)-(−)-mandelic acid production

“…Nitrile compounds are convenient and synthetically important chemical building blocks for the synthesis of a variety of high-value carboxylic acids and amides [1][2][3][4], which are important intermediates in the production of pharmaceuticals and fine chemicals. Chemical hydrolysis of nitriles typically requires strongly acidic or basic conditions and higher reaction temperatures, and usually produces unwanted byproducts.…”

Isolation and Characterization of a Nitrile-Hydrolysing Bacterium Isoptericola variabilis RGT01

“…Nitriles are toxic in nature, but can be hydrolysed to corresponding less-toxic and valuable carboxylic acids either by nitrilase (EC 3.5.5.1), or by nitrile-hydratase (EC 4.2.1.84) and amidase (EC 3.5.1.4). Nitrilases have been reported in a variety of microbes including Alcaligenes [1], Bacillus [2], Burkholderia [3], Labrenzia [4], Pseudomonas [5], Pyrococcus [6] and Rhodococcus [7]. In spite of many nitrilases reported in literature, the quest for their new sources has never ended.…”