Intermediates of thiamine catalysis immobilized on silica surface as active biocatalysts for α-ketoacid decarboxylation

Stamatis, Aggelos; Malandrinos, Gerasimos; Butler, Ian S.; Hadjiliadis, Nick; Louloudi, Maria

doi:10.1016/j.molcata.2006.11.049

Cited by 9 publications

(4 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Consequently, it eliminates the loss of activity caused by enzyme leakage from the support. Porous silica is the most commonly used supporter for the technique of immobilized enzyme [9]. However, the number of commercialized activated carriers for covalent immobilization is relatively small compared with available enzyme adsorbent materials.…”

mentioning

confidence: 99%

Influence of Silica-Derived Nano-Supporters on Cellobiase After Immobilization

Wang

Cook

et al. 2008

Appl Biochem Biotechnol

View full text Add to dashboard Cite

Core shell magnetite nanoparticle (CSMN) was successfully synthesized with diameter around 125 nm according to the determination with scanning electronic microscopy. SBA-15 with diameter around 31 nm was synthesized in our previous work as another supporter for immobilized degradation enzymes. The aim of this study was to investigate the influence of silica-derived nano-supporters on cellobiase after immobilization. With covalent method, glutaraldehyde was introduced to immobilize cellobiase. The immobilized enzyme efficiency, specific activity, and its characterization, including optimum pH, pH stability, optimum temperature for enzyme reaction, and enzyme thermal stability were investigated. Results show that the method of enzyme immobilization on both nano-supporters could improve cellobiase stability under low pH and high temperature conditions compared with the free enzyme. In the aspect of immobilization efficiency, SBA had higher amount of bounded protein than that of CSMN, but had lower specific enzyme activity than CSMN, assumably due to the change in silica surface properties caused by process of supporter synthesis.

show abstract

mentioning

confidence: 99%

Influence of Silica-Derived Nano-Supporters on Cellobiase After Immobilization

Wang

Cook

et al. 2008

Appl Biochem Biotechnol

View full text Add to dashboard Cite

show abstract

“…In fact, TPP and its derivatives were immobilized on silica, [18, 19] according to the reaction in Scheme 6.…”

Section: Biomimetic Catalysismentioning

confidence: 99%

New Perspectives on Thiamine Catalysis: From Enzymic to Biomimetic Catalysis

Stamatis

Malandrinos²,

Louloudi³

et al. 2007

Bioinorganic Chemistry and Applications

View full text Add to dashboard Cite

This paper is a brief review of the detailed mechanism of action of thiamine enzymes, based on metal complexes of bivalent transition and post-transition metals of model compounds, thiamine derivatives, synthesized and characterized with spectroscopic techniques and X-ray crystal structure determinations. It is proposed that the enzymatic reaction is initiated with a V conformation of thiamine pyrophosphate, imposed by the enzymic environment. Thiamine pyrophosphate is linked with the proteinic substrate through its pyrophosphate oxygens. In the course of the reaction, the formation of the “active aldehyde” intermediate imposes the S conformation to thiamine, while a bivalent metal ion may be linked through the N1' site of the molecule, at this stage. Finally, the immobilization of thiamine and derivatives on silica has a dramatic effect on the decarboxylation of pyruvic acid, reducing the time of its conversion to acetaldehyde from 330 minutes for the homogeneous system to less than 5 minutes in the heterogenous system.

show abstract

“…6 The xation of active biomolecules via covalent attachment to a silica surface for biotechnological processes is a remarkable synthetic approach. 7 In order to reduce the problems of using mineral acid catalysts (e.g. H 2 SO 4 and HCl) and solid acid catalysts such as clays, zeolites, sulfated metal oxides and heteropolyacids, 8 we are interested in the design of 'greener' heterogeneous catalysts.…”

Section: Introductionmentioning

confidence: 99%