Chun-Hua Han

Beijing Academy of Agriculture and Forestry Sciences, Peping, Beijing, China

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Publications (2)3.94 Total impact

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    ABSTRACT: A monomeric acid phosphatase (ACP) with a molecular mass of 72.5 kDa was purified from fresh fruiting bodies of cultured Schizophyllum commune mushroom. The isolation procedure entailed ion exchange chromatography on DEAE-cellulose, CM-cellulose, and Q-sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. It demonstrated a unique N-terminal amino acid sequence of NAPWAQIDEV, which exhibited 60% amino acid identity to that of S. commune hypothetical histidine ACP based on its genome sequence, but less than 30% amino acid identity to that of other fungal ACPs previously reported. The ACP exhibited an optimum temperature at 50 °C, an optimum pH at pH 4.6, and was considerably stable at a pH range of 4.0 to 9.0, and a temperature range of 20-40 °C. The K(m) of the purified enzyme for ρ-nitrophenyl phosphate (ρNPP) was 0.248 mM and the V(max) was 9.093 × 10(-3)  μM/min. ACP activity was strongly inhibited by Al(3+) and Fe(3+) , but enhanced by Co(2+) , Mg(2+) , and Ca(2+) at a concentration of 0.5 mM.
    No preview · Article · Oct 2013 · Journal of Basic Microbiology
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    Chun-Hua Han · Guo-Qing Zhang · He-Xiang Wang · Tzi Bun Ng
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    ABSTRACT: Abstract A monomeric hemolysin with a molecular mass of 29 kDa was isolated from fresh fruiting bodies of the split gill mushroom Schizophyllum commune. The hemolysin was purified by successive adsorption on DEAE-cellulose, carboxymethyl-cellulose and Q-Sepharose and finally gel filtration on Superdex 75. This demonstrated the N-terminal sequence ATNYNKCPGA, different from those of previously reported fungal and bacterial hemolysins. The hemolysin was stable up to 40 degrees C. Only partial activity remained at 50 and 60 degrees C. Activity was indiscernible at 70 degrees C. A pH of 6.0 was optimal for activity. The hemolytic activity was most potently inhibited by dithiothreitol, sucrose and raffinose, followed by cellobiose, maltose, rhamnose, inulin, lactose, fructose and inositol. The metal ions Cu(2+), Mg(2+), Zn(2+), Al(3+) and Fe(3+) significantly, and Pb(2+) to a lesser extent, curtailed the activity of the hemolysin. The hemolysin inhibited HIV-1 reverse transcriptase with an IC(50) of 1.8 microM.
    Preview · Article · Aug 2010 · FEMS Microbiology Letters