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Characterisation of the substrate specificity of the nitrile hydrolyzing system of the acidotolerant black yeast Exophiala oligosperma R1

The `black yeast' Exophiala oligosperma R1 can utilise various organic nitriles under acidic conditions as nitrogen sources. The induction of a phenylacetonitrile converting activity was optimised by growing the strain in the presence of different nitriles and /or complex or inorganic nitrogen...

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Autores principales: Rustler, S., Chmura, A., Sheldon, R.A., Stolz, A.
Formato: Texto
Lenguaje:English
Publicado: CBS Fungal Biodiversity Centre 2008
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2610300/
https://www.ncbi.nlm.nih.gov/pubmed/19287539
http://dx.doi.org/10.3114/sim.2008.61.17
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author Rustler, S.
Chmura, A.
Sheldon, R.A.
Stolz, A.
author_facet Rustler, S.
Chmura, A.
Sheldon, R.A.
Stolz, A.
author_sort Rustler, S.
collection PubMed
description The `black yeast' Exophiala oligosperma R1 can utilise various organic nitriles under acidic conditions as nitrogen sources. The induction of a phenylacetonitrile converting activity was optimised by growing the strain in the presence of different nitriles and /or complex or inorganic nitrogen sources. The highest nitrile hydrolysing activity was observed with cells grown with 2-cyanopyridine and NaNO(3). The cells metabolised the inducer and grew with 2-cyanopyridine as sole source of nitrogen. Cell extracts converted various (substituted) benzonitriles and phenylacetonitriles. They usually converted the isomers carrying a substituent in the meta-position with higher relative activities than the corresponding para- or ortho-substituted isomers. Aliphatic substrates such as acrylonitrile and 2-hydroxy-3-butenenitrile were also hydrolysed. The highest specific activity was detected with 4-cyanopyridine. Most nitriles were almost exclusively converted to the corresponding acids and no or only low amounts of the corresponding amides were formed. The cells hydrolysed amides only with extremely low activities. It was therefore concluded that the cells harboured a nitrilase activity. The specific activities of whole cells and cell extracts were compared for different nitriles and evidence obtained for limitation in the substrate-uptake by whole cells. The conversion of 2-hydroxy-3-butenenitrile to 2-hydroxy-3-butenoic acid at pH 4 demonstrated the unique ability of cells of E. oligosperma R1 to hydrolyse aliphatic α-hydroxynitriles under acidic conditions. The organism could grow with phenylacetonitrile as sole source of carbon, energy and nitrogen. The degradation of phenylacetonitrile presumably proceeds via phenylacetic acid, 2-hydroxyphenylacetic acid, 2,5-dihydroxyphenylacetic acid (homogentisate), maleylacetoacetate and fumarylacetoacetate.
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spelling pubmed-26103002009-03-13 Characterisation of the substrate specificity of the nitrile hydrolyzing system of the acidotolerant black yeast Exophiala oligosperma R1 Rustler, S. Chmura, A. Sheldon, R.A. Stolz, A. Stud Mycol Articles The `black yeast' Exophiala oligosperma R1 can utilise various organic nitriles under acidic conditions as nitrogen sources. The induction of a phenylacetonitrile converting activity was optimised by growing the strain in the presence of different nitriles and /or complex or inorganic nitrogen sources. The highest nitrile hydrolysing activity was observed with cells grown with 2-cyanopyridine and NaNO(3). The cells metabolised the inducer and grew with 2-cyanopyridine as sole source of nitrogen. Cell extracts converted various (substituted) benzonitriles and phenylacetonitriles. They usually converted the isomers carrying a substituent in the meta-position with higher relative activities than the corresponding para- or ortho-substituted isomers. Aliphatic substrates such as acrylonitrile and 2-hydroxy-3-butenenitrile were also hydrolysed. The highest specific activity was detected with 4-cyanopyridine. Most nitriles were almost exclusively converted to the corresponding acids and no or only low amounts of the corresponding amides were formed. The cells hydrolysed amides only with extremely low activities. It was therefore concluded that the cells harboured a nitrilase activity. The specific activities of whole cells and cell extracts were compared for different nitriles and evidence obtained for limitation in the substrate-uptake by whole cells. The conversion of 2-hydroxy-3-butenenitrile to 2-hydroxy-3-butenoic acid at pH 4 demonstrated the unique ability of cells of E. oligosperma R1 to hydrolyse aliphatic α-hydroxynitriles under acidic conditions. The organism could grow with phenylacetonitrile as sole source of carbon, energy and nitrogen. The degradation of phenylacetonitrile presumably proceeds via phenylacetic acid, 2-hydroxyphenylacetic acid, 2,5-dihydroxyphenylacetic acid (homogentisate), maleylacetoacetate and fumarylacetoacetate. CBS Fungal Biodiversity Centre 2008 /pmc/articles/PMC2610300/ /pubmed/19287539 http://dx.doi.org/10.3114/sim.2008.61.17 Text en Copyright © Copyright 2008 CBS Fungal Biodiversity Centre You are free to share - to copy, distribute and transmit the work, under the following conditions: Attribution:  You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work). Non-commercial:  You may not use this work for commercial purposes. No derivative works:  You may not alter, transform, or build upon this work. For any reuse or distribution, you must make clear to others the license terms of this work, which can be found at http://creativecommons.org/licenses/by-nc-nd/3.0/legalcode. (http://creativecommons.org/licenses/by-nc-nd/3.0/legalcode) Any of the above conditions can be waived if you get permission from the copyright holder. Nothing in this license impairs or restricts the author's moral rights.
spellingShingle Articles
Rustler, S.
Chmura, A.
Sheldon, R.A.
Stolz, A.
Characterisation of the substrate specificity of the nitrile hydrolyzing system of the acidotolerant black yeast Exophiala oligosperma R1
title Characterisation of the substrate specificity of the nitrile hydrolyzing system of the acidotolerant black yeast Exophiala oligosperma R1
title_full Characterisation of the substrate specificity of the nitrile hydrolyzing system of the acidotolerant black yeast Exophiala oligosperma R1
title_fullStr Characterisation of the substrate specificity of the nitrile hydrolyzing system of the acidotolerant black yeast Exophiala oligosperma R1
title_full_unstemmed Characterisation of the substrate specificity of the nitrile hydrolyzing system of the acidotolerant black yeast Exophiala oligosperma R1
title_short Characterisation of the substrate specificity of the nitrile hydrolyzing system of the acidotolerant black yeast Exophiala oligosperma R1
title_sort characterisation of the substrate specificity of the nitrile hydrolyzing system of the acidotolerant black yeast exophiala oligosperma r1
topic Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2610300/
https://www.ncbi.nlm.nih.gov/pubmed/19287539
http://dx.doi.org/10.3114/sim.2008.61.17
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