scholarly journals Hidden Conformations in Aspergillus niger Monoamine Oxidase are Key for Catalytic Efficiency

2019 ◽  
Vol 58 (10) ◽  
pp. 3097-3101 ◽  
Author(s):  
Christian Curado‐Carballada ◽  
Ferran Feixas ◽  
Javier Iglesias‐Fernández ◽  
Sílvia Osuna
Keyword(s):  
Aspergillus Niger ◽  
Monoamine Oxidase ◽  
Catalytic Efficiency

scholarly journals Dynamism and Cooperativity Essential for Efficient Catalysis in Aspergillus Niger Monoamine Oxidase

2019 ◽  
Author(s):  
Christian Curado-Carballada ◽  
Ferran Feixas ◽  
Sílvia Osuna
Keyword(s):  
Aspergillus Niger ◽  
Monoamine Oxidase ◽  
Active Site ◽  
Conformational Dynamics ◽  
Catalytic Efficiency ◽  
Building Blocks ◽  
Chiral Amine ◽  
Evolutionary Pathway ◽  
Accelerated Molecular Dynamics ◽  
Open States

<p><b> </b><i>Aspergillus niger </i>Monoamine Oxidase (MAO-N) is a homodimeric enzyme responsible for the oxidation of amines into the corresponding imine. Laboratory evolved variants of MAO-N in combination with a non-selective chemical reductant represents a powerful strategy for the deracemisation of chiral amine mixtures and, thus, is of interest for obtaining chiral amine building blocks. MAO-N presents a rich conformational dynamics with a flexible ß-hairpin region that can adopt closed, partially closed and open states. Despite the ß-hairpin conformational dynamics is altered along the laboratory evolutionary pathway of MAO-N, the connection between the ß-hairpin conformational dynamics and active site catalysis still remains unclear. In this work, we use accelerated molecular dynamics to elucidate the potential interplay between the ß-hairpin conformational dynamics and catalytic activity in MAO-N wild type and its evolved D5 variant. Our study reveals a delicate communication between both MAO-N subunits that impacts the active site architecture, and thus its catalytic efficiency. In both MAO-N WT and the laboratory evolved D5 variant, the ß-hairpin conformation in one of the monomers affects the productive binding of the substrate in the active site of the other subunit. However, both MAO-N WT and D5 variants show a quite different behaviour due to the distal mutations introduced experimentally with Directed Evolution. </p>

scholarly journals Dynamism and Cooperativity Essential for Efficient Catalysis in Aspergillus Niger Monoamine Oxidase

2019 ◽  
Author(s):  
Christian Curado-Carballada ◽  
Ferran Feixas ◽  
Sílvia Osuna
Keyword(s):  
Aspergillus Niger ◽  
Monoamine Oxidase ◽  
Active Site ◽  
Conformational Dynamics ◽  
Catalytic Efficiency ◽  
Building Blocks ◽  
Chiral Amine ◽  
Evolutionary Pathway ◽  
Accelerated Molecular Dynamics ◽  
Open States

<p><b> </b><i>Aspergillus niger </i>Monoamine Oxidase (MAO-N) is a homodimeric enzyme responsible for the oxidation of amines into the corresponding imine. Laboratory evolved variants of MAO-N in combination with a non-selective chemical reductant represents a powerful strategy for the deracemisation of chiral amine mixtures and, thus, is of interest for obtaining chiral amine building blocks. MAO-N presents a rich conformational dynamics with a flexible ß-hairpin region that can adopt closed, partially closed and open states. Despite the ß-hairpin conformational dynamics is altered along the laboratory evolutionary pathway of MAO-N, the connection between the ß-hairpin conformational dynamics and active site catalysis still remains unclear. In this work, we use accelerated molecular dynamics to elucidate the potential interplay between the ß-hairpin conformational dynamics and catalytic activity in MAO-N wild type and its evolved D5 variant. Our study reveals a delicate communication between both MAO-N subunits that impacts the active site architecture, and thus its catalytic efficiency. In both MAO-N WT and the laboratory evolved D5 variant, the ß-hairpin conformation in one of the monomers affects the productive binding of the substrate in the active site of the other subunit. However, both MAO-N WT and D5 variants show a quite different behaviour due to the distal mutations introduced experimentally with Directed Evolution. </p>

scholarly journals Hidden Conformations in Aspergillus niger Monoamine Oxidase are Key for Catalytic Efficiency

2019 ◽  
Vol 131 (10) ◽  
pp. 3129-3133
Author(s):  
Christian Curado‐Carballada ◽  
Ferran Feixas ◽  
Javier Iglesias‐Fernández ◽  
Sílvia Osuna
Keyword(s):  
Aspergillus Niger ◽  
Monoamine Oxidase ◽  
Catalytic Efficiency

Improving the thermostability and catalytic efficiency of glucose oxidase from Aspergillus niger by molecular evolution

2019 ◽  
Vol 281 ◽  
pp. 163-170 ◽  
Author(s):  
Tao Tu ◽  
Yuan Wang ◽  
Huoqing Huang ◽  
Yaru Wang ◽  
Xiao Jiang ◽  
...  
Keyword(s):  
Molecular Evolution ◽  
Aspergillus Niger ◽  
Glucose Oxidase ◽  
Catalytic Efficiency

Deracemisation of benzylisoquinoline alkaloids employing monoamine oxidase variants

2014 ◽  
Vol 4 (10) ◽  
pp. 3657-3664 ◽  
Author(s):  
Joerg H. Schrittwieser ◽  
Bas Groenendaal ◽  
Simon C. Willies ◽  
Diego Ghislieri ◽  
Ian Rowles ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Monoamine Oxidase ◽  
Benzylisoquinoline Alkaloids

Deracemisation of benzylisoquinoline alkaloids was performed employing a recently developed variant of monoamine oxidase from Aspergillus niger (MAO-N variant D11).

The Structure of Monoamine Oxidase from Aspergillus niger Provides a Molecular Context for Improvements in Activity Obtained by Directed Evolution

2008 ◽  
Vol 384 (5) ◽  
pp. 1218-1231 ◽  
Author(s):  
Kate E. Atkin ◽  
Renate Reiss ◽  
Valentin Koehler ◽  
Kevin R. Bailey ◽  
Sam Hart ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Monoamine Oxidase ◽  
Directed Evolution ◽  
Molecular Context

scholarly journals Gene Overexpression and Biochemical Characterization of the Biotechnologically Relevant Chlorogenic Acid Hydrolase from Aspergillus niger

2007 ◽  
Vol 73 (17) ◽  
pp. 5624-5632 ◽  
Author(s):  
Isabelle Benoit ◽  
Michèle Asther ◽  
Yves Bourne ◽  
David Navarro ◽  
Stéphane Canaan ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Chlorogenic Acid ◽  
Biochemical Characterization ◽  
Temperature Stability ◽  
Catalytic Efficiency ◽  
Molecular Size ◽  
Biochemical Properties ◽  
Acid Hydrolase ◽  
Coffee Pulp ◽  
Significant Temperature

ABSTRACT The full-length gene that encodes the chlorogenic acid hydrolase from Aspergillus niger CIRM BRFM 131 was cloned by PCR based on the genome of the strain A. niger CBS 513.88. The complete gene consists of 1,715 bp and codes for a deduced protein of 512 amino acids with a molecular mass of 55,264 Da and an acidic pI of 4.6. The gene was successfully cloned and overexpressed in A. niger to yield 1.25 g liter−1, i.e., 330-fold higher than the production of wild-type strain A. niger CIRM BRFM131. The histidine-tagged recombinant ChlE protein was purified to homogeneity via a single chromatography step, and its main biochemical properties were characterized. The molecular size of the protein checked by mass spectroscopy was 74,553 Da, suggesting the presence of glycosylation. ChlE is assembled in a tetrameric form with several acidic isoforms with pIs of around 4.55 and 5.2. Other characteristics, such as optimal pH and temperature, were found to be similar to those determined for the previously characterized chlorogenic acid hydrolase of A. niger CIRM BRFM 131. However, there was a significant temperature stability difference in favor of the recombinant protein. ChlE exhibits a catalytic efficiency of 12.5 × 106 M−1 s−1 toward chlorogenic acid (CGA), and its ability to release caffeic acid from CGA present in agricultural by-products such as apple marc and coffee pulp was clearly demonstrated, confirming the high potential of this enzyme.

scholarly journals Bioprospecting Fungal Glycosyl Hydrolases: Multi-locus Phylogenetic Analysis and Enzyme Activity Profiling for Enhanced Biomass Valorization

2020 ◽  
Author(s):  
Meenal Rastogi ◽  
Smriti Shrivastava ◽  
Pratyoosh Shukla
Keyword(s):  
Catalytic Activity ◽  
Aspergillus Niger ◽  
Value Added ◽  
Catalytic Efficiency ◽  
Morphological Characterization ◽  
Industrial Applications ◽  
Glycosyl Hydrolases ◽  
Screening Process ◽  
Subsequent Conversion ◽  
Saccharification Efficiency

Abstract Lignocelluloses comprise of celluloses and hemicelluloses which can be effectively depolymerized to obtain fermentable sugars using diverse microbial enzymes, for subsequent conversion to various value-added products. Present study reports the bioprospecting of industrially significant microorganisms and their characterization to attain xylanases with high catalytic efficiency. Four potential xylanolytic fungi were identified through distinct primary and secondary screening process of 294 isolates from samples containing plant degrades. Morphological characterization and multigene analysis (ITS rDNA, 18S rDNA, nLSU rDNA, β-tubulin and actin gene) confirmed them Aspergillus niger AUMS56, Aspergillus tubingensis AUMS60, Aspergillus niger AUMS64 and Aspergillus fumigatus AUKEMS24 and their crude xylanase activities through submerged fermentation using corncob were 18.9, 32.29, 30.68 and 15.82 U ml-1, respectively. AUMS60 and AUMS64 have highest catalytic activity of 1429 U g-1 and 1243 U g-1, respectively, all having pH and temperature optima of 6.0 and 60°C respectively, where AUMS60 produced single xylanase (Xyn60; 36 kDa) and AUMS64 secreted 2 probable isozymes (Xyn64A and Xyn64B; 33.4 and 19.8 kDa). Maximum saccharification efficiency of AUMS60 and AUMS64 were 51.1% (13 h) and 52.2% (24 h) showing enhanced catalytic activity with various cations. Present research reports potential xylanases from indigenous fungi, providing opportunity for development of bio-catalysts concoction (novelty established) for enhanced saccharification of complex lignocelluloses finding specific industrial applications for production of value-added components.

scholarly journals Molecular Characterization and Expression of a Phytase Gene from the Thermophilic Fungus Thermomyces lanuginosus

1998 ◽  
Vol 64 (11) ◽  
pp. 4423-4427 ◽  
Author(s):  
Randy M. Berka ◽  
Michael W. Rey ◽  
Kimberly M. Brown ◽  
Tony Byun ◽  
Alan V. Klotz
Keyword(s):  
Aspergillus Niger ◽  
Transcriptional Control ◽  
Specific Activity ◽  
Gene Promoter ◽  
Catalytic Efficiency ◽  
Thermophilic Fungus ◽  
Thermomyces Lanuginosus ◽  
Gene Encoding ◽  
Putative Signal Peptide ◽  
Ph Range

ABSTRACT The phyA gene encoding an extracellular phytase from the thermophilic fungus Thermomyces lanuginosus was cloned and heterologously expressed, and the recombinant gene product was biochemically characterized. The phyA gene encodes a primary translation product (PhyA) of 475 amino acids (aa) which includes a putative signal peptide (23 aa) and propeptide (10 aa). The deduced amino acid sequence of PhyA has limited sequence identity (ca. 47%) with Aspergillus niger phytase. The phyAgene was inserted into an expression vector under transcriptional control of the Fusarium oxysporum trypsin gene promoter and used to transform a Fusarium venenatum recipient strain. The secreted recombinant phytase protein was enzymatically active between pHs 3 and 7.5, with a specific activity of 110 μmol of inorganic phosphate released per min per mg of protein at pH 6 and 37°C. The Thermomyces phytase retained activity at assay temperatures up to 75°C and demonstrated superior catalytic efficiency to any known fungal phytase at 65°C (the temperature optimum). Comparison of this new Thermomyces catalyst with the well-known Aspergillus niger phytase reveals other favorable properties for the enzyme derived from the thermophilic gene donor, including catalytic activity over an expanded pH range.

Sign in / Sign up

Export Citation Format

Share Document