High constitutive peroxidase activity and constitutive thermotolerance in Neurospora crassa

DOI DOI Web Site Web Site 参考文献33件
  • Senczuk Anna Marie
    Cellular, Molecular and Microbial Biology Division, Department of Biological Sciences, University of Calgary
  • Machwe Amrita
    Cellular, Molecular and Microbial Biology Division, Department of Biological Sciences, University of Calgary
  • Kapoor Manju
    Cellular, Molecular and Microbial Biology Division, Department of Biological Sciences, University of Calgary

書誌事項

タイトル別名
  • High constitutive peroxidase activity and constitutive thermotolerance in <i>Neurospora crassa</i>

この論文をさがす

説明

<p>During the isolation of mutations in the heat-inducible hsp70-1 gene of Neurospora crassa by RIP (repeat-induced point mutations), several transformants were generated by electroporation of conidia with a plasmid harboring an incomplete copy of this gene. One isolate, designated E-45, containing ectopically integrated hsp70-1 DNA, exhibited a slow growth rate, low-temperature sensitivity, constitutive thermotolerance (without prior heat shock), and high constitutive peroxidase activity. The constitutive form of peroxidase (CP) was distinguishable from the heat-inducible form (HIP) by immunoinactivation employing polyclonal antiserum against the latter enzyme and by electrophoretic resolution in nondenaturing polyacrylamide gels. This enzyme was purified to near homogeneity and some of its properties examined. The relative molecular mass of native CP was in the range of 118–136kDa, as estimated by gel filtration analysis on size exclusion matrices, whereas SDS-PAGE analysis yielded a size of ~37kDa for the polypeptide. Substrate saturation kinetics studies were conducted using ABTS [2,2'-azino-bis (3-ethylbenzthiazole-6-sulfonic acid)] and H2O2 as substrates: Km, Vmax, and Kcat values for H2O2 were ~22μM, ~447nmolmg−1, and 0.33s−1, respectively, and those for ABTS were ~55μM, ~453nmolmg−1, and 0.3s−1, respectively. Guaiacol was not used as a substrate by this enzyme. CP peroxidase was shown to be a heme-containing enzyme, stable at temperatures up to 58°C.</p>

収録刊行物

  • Mycoscience

    Mycoscience 44 (2), 129-137, 2003

    一般社団法人 日本菌学会

参考文献 (33)*注記

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ