Mass spectrometric analysis of peptides from an immobilized lipase: focus on oxidative modifications

Törnvall, Ulrika; Fürst, Camilla Melin; Hatti‐Kaul, Rajni; Hedström, Martin

doi:10.1002/rcm.4208

Cited by 21 publications

(15 citation statements)

References 27 publications

(27 reference statements)

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“…8 also indicates an activation effect with each subsequent run conducted on the same day, especially with high H 2 O 2 concentration. This effect has earlier also been reported and attributed to the deactivation cycle of lipase B which involves an intermediate more activated state of the enzyme [27]. It was seen that overall the activity of the enzymes dropped significantly faster when 17.5 M H 2 O 2 was used.…”

Section: Stability and Reusability Of Silcoat-nz435supporting

confidence: 76%

Efficient Chemo‐Enzymatic Epoxidation Using silcoat‐Novozym^®435: Characterizing the Multiphase System

et al. 2012

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Silicone composites of Novozym®435 (silcoat-NZ435) demonstrate improved leaching and mechanical stability compared to native Novozym®435 (NZ435). Here, the application scope of this novel enzyme preparation has been broadened significantly by the transfer from single-phase esterification to a complex chemoenzymatic epoxidation reaction in a three-phase system. The reaction gave up to 80 % yields with almost 100 % selectivity in 50 h when operated in the absence of mass transfer limitations. Characterization of the system revealed that octanoic acid inhibited the reaction at concentrations around 6 M. The silcoat-NZ435 catalyst could be reused over five days with less than 50 % loss in activity when 5 M H 2 O 2 was present. H 2 O 2 was also identified as the component which deactivates the enzyme at high concentration (17.5 M) demanding spatial separation of the silcoat-NZ435 for optimal operation.

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Section: Stability and Reusability Of Silcoat-nz435supporting

confidence: 76%

Efficient Chemo‐Enzymatic Epoxidation Using silcoat‐Novozym^®435: Characterizing the Multiphase System

et al. 2012

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“…The effect on the primary, secondary, tertiary and quaternary structure of CALB upon exposure to hydrogen peroxide has been investigated [64,247]. The presence of protein aggregates whose concentration increased with increasing incubation time has been reported during this process.…”

Section: Immobilizationmentioning

confidence: 99%

Hydrogen Peroxide in Biocatalysis. A Dangerous Liaison

Hernández

Berenguer-Murcia²,

Rodrigues³

et al. 2012

COC

137

107

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Hydrogen peroxide is a substrate or side-product in many enzyme-catalyzed reactions. For example, it is a side-product of oxidases, resulting from the re-oxidation of FAD with molecular oxygen, and it is a substrate for peroxidases and other enzymes. However, hydrogen peroxide is able to chemically modify the peptide core of the enzymes it interacts with, and also to produce the oxidation of some cofactors and prostetic groups (e.g., the hemo group). Thus, the development of strategies that may permit to increase the stability of enzymes in the presence of this deleterious reagent is an interesting target. This enhancement in enzyme stability has been attempted following almost all available strategies: site-directed mutagenesis (eliminating the most reactive moieties), medium engineering (using stabilizers), immobilization and chemical modification (trying to generate hydrophobic environments surrounding the enzyme, to confer higher rigidity to the protein or to generate oxidation-resistant groups), or the use of systems capable of decomposing hydrogen peroxide under very mild conditions. If hydrogen peroxide is just a side-product, its immediate removal has been reported to be the best solution. In some cases, when hydrogen peroxide is the substrate and its decomposition is not a sensible solution, researchers coupled one enzyme generating hydrogen peroxide "in situ" to the target enzyme resulting in a continuous supply of this reagent at low concentrations thus preventing enzyme inactivation.This review will focus on the general role of hydrogen peroxide in biocatalysis, the main mechanisms of enzyme inactivation produced by this reactive and the different strategies used to prevent enzyme inactivation caused by this "dangerous liaison". Outlook

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“…In fact, the reaction system is mild and friendly for enzymes because there are no substances, e.g. peroxides and acids that can lead to inactivation of enzyme …”

Section: Model Developmentmentioning

confidence: 99%

“…peroxides and acids that can lead to inactivation of enzyme. [26][27][28][29] Based on the earlier assumptions, an ordered sequential mechanism of the enzymatic reaction 30-33 is discussed later. As shown in Scheme 2, the mechanism of reactions (1)-(4) is proposed and schematically illustrated.…”

Section: Wileyonlinelibrarycom/jctbmentioning

confidence: 99%

Synthesis of mitomycin analogs catalyzed by coupling of laccase with lipase and the kinetic model

Zhang

Sun

Ren

et al. 2020

J of Chemical Tech & Biotech

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BACKGROUND Mitomycin C (MMC) is one of the most important members of the mitomycin family that have been widely used as a strong antineoplastic antibiotic for treating various tumors. In this study, enzymatic oxidation/amination reaction of 2‐methyl‐1,4‐hydroquinone with n‐butylamine was carried out to synthesize 2‐methyl‐3‐n‐butylaminoyl‐1,4‐benzoquinone mitomycin analogs. RESULTS A kinetic model was developed based on an ordered sequential mechanism for this cascade reaction system catalyzed by two enzymes, which revealed that the limiting step of the system was the laccase‐mediated oxidation of 2‐methyl‐3‐n‐butylaminoyl‐4‐hydro‐1‐quinone and removing the limiting step resulted in a yield increase from 88.3% to 96.7%. CONCLUSION The developed kinetic model fitted the test data very well, indicating that the reactions catalyzed by coupling of laccase with lipase might follow the ordered sequential mechanism with product inhibition. Synthesis of mitomycin analogs catalyzed by coupling of laccase with lipase has great potential for practical application. © 2020 Society of Chemical Industry

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Mass spectrometric analysis of peptides from an immobilized lipase: focus on oxidative modifications

Cited by 21 publications

References 27 publications

Efficient Chemo‐Enzymatic Epoxidation Using silcoat‐Novozym^®435: Characterizing the Multiphase System

Efficient Chemo‐Enzymatic Epoxidation Using silcoat‐Novozym^®435: Characterizing the Multiphase System

Hydrogen Peroxide in Biocatalysis. A Dangerous Liaison

Synthesis of mitomycin analogs catalyzed by coupling of laccase with lipase and the kinetic model

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Mass spectrometric analysis of peptides from an immobilized lipase: focus on oxidative modifications

Cited by 21 publications

References 27 publications

Efficient Chemo‐Enzymatic Epoxidation Using silcoat‐Novozym®435: Characterizing the Multiphase System

Efficient Chemo‐Enzymatic Epoxidation Using silcoat‐Novozym®435: Characterizing the Multiphase System

Hydrogen Peroxide in Biocatalysis. A Dangerous Liaison

Synthesis of mitomycin analogs catalyzed by coupling of laccase with lipase and the kinetic model

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Product

Resources

About

Efficient Chemo‐Enzymatic Epoxidation Using silcoat‐Novozym^®435: Characterizing the Multiphase System

Efficient Chemo‐Enzymatic Epoxidation Using silcoat‐Novozym^®435: Characterizing the Multiphase System