Peroxidases are ubiquitous enzymes that catalyze a variety of oxygen-transfer reactions and are t... more Peroxidases are ubiquitous enzymes that catalyze a variety of oxygen-transfer reactions and are thus potentially useful for industrial and biomedical applications. Over the last decade, several studies have shown that peroxidases isolated from the leaves of different kinds of palm trees such as the royal palm (Roystonea regia), the date palm (Phoenix dactylifera), the African oil palm (Elaeis guineensis), the ruffle palm (Aiphanes cariotifolia) and the windmill palms (Trachycarpus fortunei and Chamaerops excelsa) exhibit higher activity and stability than commercially available peroxidases isolated from, for example, horseradish roots (Armoracia rusticana) and soybean (Glycine max). Here, the structure, thermal denaturation, and the catalytic cycle of peroxidases from palm trees are reviewed and compared with those of other plant peroxidases. In addition, we report the biotechnological potential of palm peroxidases and their implications in cellular aging and diseases, such as Refsum’s and Alzheimer’s diseases. This paper summarizes the main characteristics of the palm peroxidases studied.Peer reviewe
International Journal of Biological Macromolecules, 2015
New plant peroxidase has been isolated to homogeneity from the white Spanish broom Cytisus multif... more New plant peroxidase has been isolated to homogeneity from the white Spanish broom Cytisus multiflorus. The enzyme purification steps included homogenization, NH(4)SO(4) precipitation, extraction of broom colored compounds and consecutive chromatography on Phenyl-Sepharose, HiTrap™ SP HP and Superdex-75 and 200. The novel peroxidase was characterized as having a molecular weight of 50 ± 3 kDa. Steady-state tryptophan fluorescence and far-UV circular dichroism (CD) studies, together with enzymatic assays, were carried out to monitor the structural stability of C. multiflorus peroxidase (CMP) at pH 7.0. Thus changes in far-UV CD corresponded to changes in the overall secondary structure of enzyme, while changes in intrinsic tryptophan fluorescence emission corresponded to changes in the tertiary structure of the enzyme. It is shown that the process of CMP denaturation can be interpreted with sufficient accuracy in terms of the simple kinetic scheme, N ⟶ kD, where k is a first-order kinetic constant that changes with temperature following the Arrhenius equation; N is the native state, and D is the denatured state. On the basis of this model, the parameters of the Arrhenius equation were calculated.
Detailed differential scanning calorimetry (DSC), steady-state tryptophan fluorescence and far-UV... more Detailed differential scanning calorimetry (DSC), steady-state tryptophan fluorescence and far-UV and visible CD studies, together with enzymatic assays, were carried out to monitor the thermal denaturation of horseradish peroxidase isoenzyme c (HRPc) at pH 3.0. The spectral parameters were complementary to the highly sensitive but integral method of DSC. Thus, changes in far-UV CD corresponded to changes in the overall secondary structure of the enzyme, while that in the Soret region, as well as changes in intrinsic tryptophan fluorescence emission, corresponded to changes in the tertiary structure of the enzyme. The results, supported by data about changes in enzymatic activity with temperature, show that thermally induced transitions for peroxidase are irreversible and strongly dependent upon the scan rate, suggesting that denaturation is under kinetic control. It is shown that the process of HRPc denaturation can be interpreted with sufficient accuracy in terms of the simple kinetic scheme N -->k D where k is a first-order kinetic constant that changes with temperature, as given by the Arrhenius equation; N is the native state, and D is the denatured state. On the basis of this model, the parameters of the Arrhenius equation were calculated.
Peroxidases are ubiquitous enzymes that catalyze a variety of oxygen-transfer reactions and are t... more Peroxidases are ubiquitous enzymes that catalyze a variety of oxygen-transfer reactions and are thus potentially useful for industrial and biomedical applications. Over the last decade, several studies have shown that peroxidases isolated from the leaves of different kinds of palm trees such as the royal palm (Roystonea regia), the date palm (Phoenix dactylifera), the African oil palm (Elaeis guineensis), the ruffle palm (Aiphanes cariotifolia) and the windmill palms (Trachycarpus fortunei and Chamaerops excelsa) exhibit higher activity and stability than commercially available peroxidases isolated from, for example, horseradish roots (Armoracia rusticana) and soybean (Glycine max). Here, the structure, thermal denaturation, and the catalytic cycle of peroxidases from palm trees are reviewed and compared with those of other plant peroxidases. In addition, we report the biotechnological potential of palm peroxidases and their implications in cellular aging and diseases, such as Refsum’s and Alzheimer’s diseases. This paper summarizes the main characteristics of the palm peroxidases studied.Peer reviewe
International Journal of Biological Macromolecules, 2015
New plant peroxidase has been isolated to homogeneity from the white Spanish broom Cytisus multif... more New plant peroxidase has been isolated to homogeneity from the white Spanish broom Cytisus multiflorus. The enzyme purification steps included homogenization, NH(4)SO(4) precipitation, extraction of broom colored compounds and consecutive chromatography on Phenyl-Sepharose, HiTrap™ SP HP and Superdex-75 and 200. The novel peroxidase was characterized as having a molecular weight of 50 ± 3 kDa. Steady-state tryptophan fluorescence and far-UV circular dichroism (CD) studies, together with enzymatic assays, were carried out to monitor the structural stability of C. multiflorus peroxidase (CMP) at pH 7.0. Thus changes in far-UV CD corresponded to changes in the overall secondary structure of enzyme, while changes in intrinsic tryptophan fluorescence emission corresponded to changes in the tertiary structure of the enzyme. It is shown that the process of CMP denaturation can be interpreted with sufficient accuracy in terms of the simple kinetic scheme, N ⟶ kD, where k is a first-order kinetic constant that changes with temperature following the Arrhenius equation; N is the native state, and D is the denatured state. On the basis of this model, the parameters of the Arrhenius equation were calculated.
Detailed differential scanning calorimetry (DSC), steady-state tryptophan fluorescence and far-UV... more Detailed differential scanning calorimetry (DSC), steady-state tryptophan fluorescence and far-UV and visible CD studies, together with enzymatic assays, were carried out to monitor the thermal denaturation of horseradish peroxidase isoenzyme c (HRPc) at pH 3.0. The spectral parameters were complementary to the highly sensitive but integral method of DSC. Thus, changes in far-UV CD corresponded to changes in the overall secondary structure of the enzyme, while that in the Soret region, as well as changes in intrinsic tryptophan fluorescence emission, corresponded to changes in the tertiary structure of the enzyme. The results, supported by data about changes in enzymatic activity with temperature, show that thermally induced transitions for peroxidase are irreversible and strongly dependent upon the scan rate, suggesting that denaturation is under kinetic control. It is shown that the process of HRPc denaturation can be interpreted with sufficient accuracy in terms of the simple kinetic scheme N -->k D where k is a first-order kinetic constant that changes with temperature, as given by the Arrhenius equation; N is the native state, and D is the denatured state. On the basis of this model, the parameters of the Arrhenius equation were calculated.
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Papers by Valery Shnyrov