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.
Martínková
Ludmila
L
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.
Vejvoda
Vojtěch
V
Centre of Biocatalysis and Biotransformation, Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, CZ-142 20 Prague, Czech Republic.
Kaplan
Ondřej
O
Centre of Biocatalysis and Biotransformation, Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, CZ-142 20 Prague, Czech Republic.
Kubáč
David
D
Centre of Biocatalysis and Biotransformation, Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, CZ-142 20 Prague, Czech Republic.
Malandra
Anna
A
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.
Cantarella
Maria
M
Department of Chemistry, Chemical Engineering and Materials, University of L´Aquila, Monteluco di Roio, I-67040 L´Aquila, Italy.
Bezouška
Karel
K
Department of Biochemistry, Faculty of Science, Charles University Prague, Hlavova 8, CZ-128 40 Prague, Czech Republic.
Křen
Vladimír
V
Centre of Biocatalysis and Biotransformation, Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, CZ-142 20 Prague, Czech Republic.
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