Surface functionalization of chitosan-coated magnetic nanoparticles for covalent immobilization of yeast alcohol dehydrogenase from Saccharomyces cerevisiae

2010 ◽  
Vol 322 (24) ◽  
pp. 3862-3868 ◽  
Author(s):  
Gui-yin Li ◽  
Zhi-de Zhou ◽  
Yuan-jian Li ◽  
Ke-long Huang ◽  
Ming Zhong
2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Katja Vasić ◽  
Željko Knez ◽  
Maja Leitgeb

Abstract A novel method is described for the immobilization of alcohol dehydrogenase (ADH) from Saccharomyces cerevisiae onto carboxymethyl dextran (CMD) coated magnetic nanoparticles (CMD-MNPs) activated with epoxy groups, using epichlorohydrin (EClH). EClH was used as an activating agent to bind ADH molecules on the surface of CMD-MNPs. Optimal immobilization conditions (activating agent concentration, temperature, rotation speed, medium pH, immobilization time and enzyme concentration) were set to obtain the highest expressed activity of the immobilized enzyme. ADH that was immobilized onto epoxy-activated CMD-MNPs (ADH-CMD-MNPs) maintained 90% of the expressed activity. Thermal stability of ADH-CMD-MNPS after 24 h at 20 °C and 40 °C yielded 79% and 80% of initial activity, respectively, while soluble enzyme activity was only 19% at 20 °C and the enzyme was non-active at 40 °C. Expressed activity of ADH-CMD-MNPs after 21 days of storage at 4 °C was 75%. Kinetic parameters (KM, vmax) of soluble and immobilized ADH were determined, resulting in 125 mM and 1.2 µmol/min for soluble ADH, and in 73 mM and 4.7 µmol/min for immobilized ADH.


Biologia ◽  
2014 ◽  
Vol 69 (6) ◽  
Author(s):  
Pavol Utekal ◽  
Csaba Tóth ◽  
Anikó Illésová ◽  
Pavol Koiš ◽  
Lucia Bocánová ◽  
...  

AbstractSix-carbon aldehydes and alcohols belong to flavours and fragrances with wide application in the food, feed, cosmetic, chemical and pharmaceutical sectors. In the present study, we prepared the expression system for production of recombinant yeast alcohol dehydrogenase 1 (YADH1) from Saccharomyces cerevisiae which is suitable also for catalysis of the interconversion of C-6 aldehydes and alcohols. We have demonstrated that an effective three-step strategy can overcome the insolubility problems during YADH1 production in Escherichia coli. We used trxB and gor deficient expression strain, decreased concentration of isopropyl β-D-1-thiogalactopyranoside and lowered temperature to 20°C during induction. Finally, kinetic parameters of recombinant YADH1 were determined and we concluded it is a promising enzyme also for the interconversion of C-6 alcohols/aldehydes in green note volatile production.


1978 ◽  
Vol 253 (23) ◽  
pp. 8414-8419
Author(s):  
H. Jörnvall ◽  
H. Eklund ◽  
C.I. Brändén

2010 ◽  
Vol 2 (10) ◽  
pp. 2789-2796 ◽  
Author(s):  
Gyu Leem ◽  
Shishan Zhang ◽  
Andrew C. Jamison ◽  
Eduard Galstyan ◽  
Irene Rusakova ◽  
...  

Genetics ◽  
1987 ◽  
Vol 116 (4) ◽  
pp. 531-540
Author(s):  
Aileen K W Taguchi ◽  
Elton T Young

ABSTRACT The alcohol dehydrogenase II (ADH2) gene of the yeast, Saccharomyces cerevisiae, is not transcribed during growth on fermentable carbon sources such as glucose. Growth of yeast cells in a medium containing only nonfermentable carbon sources leads to a marked increase or derepression of ADH2 expression. The recessive mutation, adr6-1, leads to an inability to fully derepress ADH2 expression and to an inability to sporulate. The ADR6 gene product appears to act directly or indirectly on ADH2 sequences 3' to or including the presumptive TATAA box. The upstream activating sequence (UAS) located 5' to the TATAA box is not required for the Adr6- phenotype. Here, we describe the isolation of a recombinant plasmid containing the wild-type ADR6 gene. ADR6 codes for a 4.4-kb RNA which is present during growth both on glucose and on nonfermentable carbon sources. Disruption of the ADR6 transcription unit led to viable cells with decreased ADHII activity and an inability to sporulate. This indicates that both phenotypes result from mutations within a single gene and that the adr6-1 allele was representative of mutations at this locus. The ADR6 gene mapped to the left arm of chromosome XVI at a site 18 centimorgans from the centromere.


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