Activity of lignin peroxidase

Nie, G., and Aust, S. D., 1997, Effect of calcium on the reversible thermal activation of lignin peroxidase, Arch. Biochem. Biophys. 337 225n231. 

Water/TX-100/[C mim][PF ] microemulsions were used as reaction media in enzymatic reactions. The catalytic activities of alcohol dehydrogenase in this ternary system were determined, and it was found to be greatly improved as compared with those in pure [Bmim][PF ] [62].The same system was used in order to analyze the effect on the catalytic activity of lignin peroxidase and laccase [63]. The catalytic behavior and stability of lipases from Candida rugosa, Chromobacterium viscosum, and Thermomyces lanuginosa in these microemulsions were investigated and compared to other microheterogeneous media used so far for enzyme-catalyzed reactions [64]. 

INHIBITION OF THE VERATRYL ALCOHOL OXIDASE ACTIVITY OF LIGNIN PEROXIDASE H8 BY HYDROXYLAMINODINITROTOLUENE... 

Figure 9. Effect of increasing amounts of hydroxylaminodinitrotoluenes on the veratryl alcohol oxidase activity of lignin peroxidase H8 (32). The reaction mixture contained in a final volume of 600 pi 0.05 pM lignin peroxidase H8, 40 mM sodium tartrate buffer, pH 3.5, 130 pM H2O2, 5.6 mM veratryl alcohol, and various concentrations of hydroxylaminodinitrotoluene (both isomers) [pM] 0, 5,A 10, 16, O 21, A 24, .

Kimura, M., Michizoe, J., Fumsaki, S., Goto, M., Tanaka, H., and Wariishi, H. (2004) Activation of lignin peroxidase in organic media by reversed micelles. Biotechnol. Bioeng., 88, 495-501. 

Kersten PJ (1990) Glyoxal oxidase of Phanerochaete chrysosporium its characterization and activation by lignin peroxidase. Proc Natl Acad Sci USA 87 2936-2940. 

Lignin peroxidase, secreted by the white-rot fungus Phanerochaete chrysosporium in response to nutrient deprivation, catalyzes the H202-dependent oxidation of non-phenolic aromatic substrates. The present report summarizes the kinetic and structural characteristics of lignin peroxidase isozymes. Our results indicate that the active site of lignin peroxidase is more electron deficient than other peroxidases. As a result, the redox potential of the heme active site is higher, the heme active site is more reactive and the oxycomplex is more stable than that of other peroxidases. Also discussed is the heme-linked ionization of lignin peroxidase. 

Activity Assays. The standard activity assay mixture of 3 ml contained about 0.1 U/ml lignin peroxidase, 0.4 mM veratryl alcohol (Fluka, purum >97%) and 0.1M sodium tartrate, pH 3.0. The reaction was started by adding 15 fil of 54 mM H2O2 to make a final concentration of 0.28 mM in the reaction. The production of veratraldehyde was followed by recording the change of absorbance for 12 seconds at 310 nm in a cuvette which was thermostated to 37°C. The reaction was started 24 seconds before the recording. One unit of lignin peroxidase is defined as the amount of enzyme required to oxidize one imol of veratryl alcohol to veratraldehyde in one minute. 

Figure 2. Purification of lignin peroxidases by anion exchange chromatography. Enzyme activity (U/1) O Absorbance at 405 nm Absorbance at 280 nm.

Inhibition of enzyme activity was not used to assess the antibody-antigen reaction of lignin-peroxidase, as the addition of control serum to enzyme reaction mixtures increased the pH above the pH specificity of the... 

Unfortunately, not all PAHs are substrates for peroxidases. A correlation has been found between the ionization potential (IP) of PAHs and the specific activity of manganese peroxidase, lignin peroxidase, hemoglobin, and chloroperoxidase. A threshold value of IP was found for each enzyme. Lignin peroxidase oxidizes PAHs with IP = 7.55 eV [87], while manganese peroxidase oxidizes PAHs with IP... 

Barr DP, Aust SD (1994) Conversion of lignin peroxidase compound III to active enzyme by cation radicals. Arch Biochem Biophys 312 511-515... 

Doyle WA, Smith AT (1996) Expression of lignin peroxidase H8 in Escherichia coli folding and activation of the recombinant enzyme with Ca2+ and haem. Biochem J 315 ... 

Fig. 4. Active-site structure of lignin peroxidase. The dashed lines represent H-honds between N1 of the distal His47 and the side-chain carbonyl of Asn84, and N1 of the proximal Hisl76 and the side-chain carboxylate of Asp238. This diagram was generated using the X-ray coordinates for the 2.0-A structure of LIP (5).

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