The preparation and properties of hornblende as a support for immobilized invertase

Thornton, David J.; Flynn, Albert; Johnson, Donna; Ryan, P.

doi:10.1002/bit.260171110

Cited by 40 publications

(7 citation statements)

References 10 publications

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“…In the final state (E d ), the enzyme has lost all its activity. Such a deactivation pattern has been reported for several enzymes such as glucoamylase immobilized on collagen (Brillouet et al 1977), b-galactosidase immobilized on alumina (Charles et al 1975) and b-fructofuranosidase immobilized on porous glass (Thornton et al 1975). In our case, a grace period of time (t g ) was also observed at 408C in which the soluble and immobilized SlPVA apparently suffered no loss of enzymatic activity.…”

Section: Effect Of Ph On Activity Of Immobilized Penicillin Acylasementioning

confidence: 89%

Kinetic and microstructural characterization of immobilized penicillin acylase fromStreptomyces lavendulaeon Sepabeads EC-EP

Hormigo

Mata

Castillón

et al. 2009

Biocatalysis and Biotransformation

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Recombinant penicillin acylase from Streptomyces lavendulae was covalently bound to epoxy-activated Sepabeads EC-EP303 † . Optimization of the immobilization process led to a homogeneous distribution of the enzyme on the support surface avoiding the attachment of enzyme aggregates, as shown by confocal electron microscopy. The optimal immobilized biocatalyst had a specific enzymatic activity of 26.2 IU g wet carrier (1 in the hydrolysis of penicillin V at pH 8.0 and 408C. This biocatalyst showed the highest activity at pH 8.5 and 658C, 1.5 pH units lower and 58C higher than its soluble counterpart. Substrate specificity of the derivative also showed its ability to efficiently hydrolyze other natural aliphatic penicillins such as penicillins K, F and dihydroF. The immobilized enzyme was highly stable at 408C and pH 8.0 (t 1/2 0625 h vs. t 1/2 0397 h for the soluble enzyme), and it could be recycled for at least 30 consecutive batch reactions without loss of catalytic activity.

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Section: Effect Of Ph On Activity Of Immobilized Penicillin Acylasementioning

confidence: 89%

Kinetic and microstructural characterization of immobilized penicillin acylase fromStreptomyces lavendulaeon Sepabeads EC-EP

Hormigo

Mata

Castillón

et al. 2009

Biocatalysis and Biotransformation

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“…The initial phase was termed the ‘grace period’. Thermal inactivation showing a ‘grace period’ was observed for several mesophilic enzymes: luciferase and urease [41], and fructofuranosidase [42]. It was also reported for wild‐type HuBuChE during the first 5 min of ultrasound inactivation kinetics [43] and after pressure/temperature exposure [28].…”

mentioning

confidence: 88%

Pressure and heat inactivation of recombinant human acetylcholinesterase

Cléry-Barraud

Ordentlich

Grosfeld

et al. 2002

European Journal of Biochemistry

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The effects of pressure on structure and activity of recombinant human acetylcholinesterase (rHuAChE) were investigated up to a pressure of 300 MPa using gel electrophoresis under elevated hydrostatic pressure, fluorescence of bound 8-anilinonaphthalene-1-sulfonate (ANS) and activity measurements following exposure to high pressure. Study of wildtype enzyme and three single mutants (D74N, E202Q, E450A) and one sextuple mutant (E84Q/E292A/D349N/ E358Q/E389Q/D390N) showed that pressure exerts a differential action on wild-type rHuAChE and its mutants, allowing estimation of the contribution of carboxylic amino acid side-chains to enzyme stability. Mutation of negatively charged residues D74 and E202 by polar side-chains strengthened heat or pressure stability. The mutation E450A and the sextuple mutation caused destabilization of the enzyme to pressure. Thermal inactivation data on mutants showed that all of them were stabilized against temperature. In conclusion, pressure and thermal stability of mutants provided evidence that the residue E202 is a determinant of structural and functional stability of HuAChE.

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“…Some other supports used for urea biosensor fabrication include: bilayer lipid membranes [108], carbon paste electrodes [109], composite hydrogel membranes [110], gelatin membranes [111], inorganic matrices (e.g., clays, laponite and Zn-Al layered double hydroxides matrices) [112,113], SiO 2 films, glass beads, diatomite, silica, porous glass, hornblende and molecular sieves [114][115][116][117][118].…”

Section: Miscellaneous Matrices For Urea Biosensingmentioning

confidence: 99%