Two Kinds Of Edible Fungi Peroxidase And Laccase Physiological And Biochemical Studies And Two Black Fungus Strains Ddrt Pcr Analysis

By using DEAE-Cellulose. CM-Cellulose. ConA-Sepharose. Q-Sepharose and gel filtration by fast protein liquid chromatography on Superdex75, a new peroxidase and a new laccase were isolated from Pleurotus pulmonarius fruiting body and Hericium coralloides dried body, respectively.Pleurotus plumonarius peroxidase is a monomer with55-kDa and its N-terminal amino acid sequence was ADNPGDDGN. The optimal pH and temperature for the enzyme were4.0and70℃, respectively. All enzyme activity was destroyed after exposured in100℃for10minutes. The peroxidase did not exhibit HIV-1reverse transcriptase inhibitory activity and antifungal activity.Hericium coralloides laccase is a monomeric protein with65kDa and its N-terminal amino acid sequence was AVGDDTPQLY. T which exhibits partial sequence homology to previously isolated laccases. Optimum activity was observed at pH2.2and at40℃. The enzyme showed activity toward a variety of substrates, the most sensitive of which was2,2’-azinobis [3-ethylbenzothiazolone-6-sulfonic acid] diammonium salt (ABTS). The degradation activity toward substrates was ABTS> N,N-dimethyl-1,4-phenylenediamine> catechol>2-methylcatechol> pyrogallol. The laccase activity can be remarkably inhibited by Fe3+and Hg2+. The laccase did not exert any antiproliferative activity against Hep G2or MCF7tumor cell lines at a concentration of60μM, unlike some previously reported mushroom proteins, but showed significant activity toward human immunodeficiency virus-1(HIV-1) reverse transcriptase with an IC50of0.06μM.Differential-display reverse transcription-PCR (DDRT-PCR) was used to investigate the difference of gene expression between degeneration strain and wild type strain of Auricularia auricula-judae, and7cDNA fragments were obtained. Four fragments showed high sequence similarity to known gene products with putative maturase. nuclear movement protein nudC, cytochrome c oxidase subunit Ⅱ and pG1protein. Three fragments showed high sequence similarity to some other hypothetical proteins of several kinds of organisms. The results of this study provided a basis for further study of the molecular mechanism of degradation strain of Auricularia auricula-judae.