Fungal nitrilases as biocatalysts: Recent developments.
Of the numerous putative fungal nitrilases available from protein databases only a few enzymes were purified and characterized. The purified nitrilases from Fusarium solani, Fusarium oxysporum f. sp. melonis and Aspergillus niger share a preference for (hetero)aromatic nitriles, temperature optima between 40 and 50 degrees C and pH optima in the slightly alkaline region. On the other hand, they differ in their chemoselectivity, i.e. their tendency to produce amides as by-products. The production of fungal nitrilases is increased by up to three orders of magnitude on the addition of 2-cyanopyridine to the culture media. The whole-cell and subcellular biocatalysts were immobilized by various methods (LentiKats(R); adsorption on hydrophobic or ion exchange resins; cross-linked enzyme aggregates). Operational stability was examined using continuous stirred membrane bioreactors. Fungal nitrilases appear promising for biocatalytic applications and biodegradation of nitrile environmental contaminants.
Centre of Biocatalysis and Biotransformation, Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, CZ-142 20 Prague, Czech Republic. Electronic address: martinko@biomed.cas.cz.
Ludmila
L
Martínková
Centre of Biocatalysis and Biotransformation, Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, CZ-142 20 Prague, Czech Republic.
Vojtěch
V
Vejvoda
Centre of Biocatalysis and Biotransformation, Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, CZ-142 20 Prague, Czech Republic.
Ondřej
O
Kaplan
Centre of Biocatalysis and Biotransformation, Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, CZ-142 20 Prague, Czech Republic.
David
D
Kubáč
Centre of Biocatalysis and Biotransformation, Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, CZ-142 20 Prague, Czech Republic; Department of Chemistry, Chemical Engineering and Materials, University of L´Aquila, Monteluco di Roio, I-67040 L´Aquila, Italy.
Anna
A
Malandra
Department of Chemistry, Chemical Engineering and Materials, University of L´Aquila, Monteluco di Roio, I-67040 L´Aquila, Italy.
Maria
M
Cantarella
Department of Biochemistry, Faculty of Science, Charles University Prague, Hlavova 8, CZ-128 40 Prague, Czech Republic.
Karel
K
Bezouška
Centre of Biocatalysis and Biotransformation, Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, CZ-142 20 Prague, Czech Republic.
Vladimír
V
Křen
D000619:Aminohydrolases / Q000378:metabolism*; D055162:Biocatalysis; D004795:Enzyme Stability; D005658:Fungi / Q000145:classification / Q000201:enzymology*; D013045:Species Specificity; D013379:Substrate Specificity
D000619:Aminohydrolases; C021867:nitrilase