CAJ | 학술논문

通过对参环毛蚓肠道组织提取液进行DEAE阴离子交换及凝胶过滤层析,获得参环毛蚓单一的内源纤维素酶的活性组分. 根据AlpHaEaseFC~(TM)软件计算出该组分分子质量约为45 ku,命名为Cx1. 羧甲基纤维素钠(sodium carboxymethylcellulose,CMC)法对Cx1进行酶学性质分析. 分析结果显示:对于底物羧甲基纤维素钠,Cx1的米氏常数(K_m)为0.289 mg/mL,V_(max)为0.446 U·mL~(-1)·min~(-1),反应最适温度为55 ℃,最适pH为6.0,在40～60 ℃、pH 5.0～8.0具有较好的热稳定性和pH稳定性,其相对酶活力都能保持在55%以上. Ag~+和Ba~(2+)对Cx1起显著激活作用, K~+、 Zn~(2+)、 Mg~(2+)、Ca~(2+)、NH~+_4、Ni~(2+)、Na~+、Pb~(2+)部分抑制酶活性,Cu~(2+)离子对Cx1有完全抑制作用,而Fe~(2+)对酶活力无明显影响.
통과대삼배모인장도조직제취액진행DEAE음리자교환급응효과려층석,획득삼배모인단일적내원섬유소매적활성조분. 근거AlpHaEaseFC~(TM)연건계산출해조분분자질량약위45 ku,명명위Cx1. 최갑기섬유소납(sodium carboxymethylcellulose,CMC)법대Cx1진행매학성질분석. 분석결과현시:대우저물최갑기섬유소납,Cx1적미씨상수(K_m)위0.289 mg/mL,V_(max)위0.446 U·mL~(-1)·min~(-1),반응최괄온도위55 ℃,최괄pH위6.0,재40～60 ℃、pH 5.0～8.0구유교호적열은정성화pH은정성,기상대매활력도능보지재55%이상. Ag~+화Ba~(2+)대Cx1기현저격활작용, K~+、 Zn~(2+)、 Mg~(2+)、Ca~(2+)、NH~+_4、Ni~(2+)、Na~+、Pb~(2+)부분억제매활성,Cu~(2+)리자대Cx1유완전억제작용,이Fe~(2+)대매활력무명현영향.
The endogenous cellulase from the gut of Pheretima aspergillum by homogenization was separated by DEAE anion exchanger and gel filtration chromatography, and a single band with cellulase activity was identified by SDS-PAGE and zymography. Its molecular mass was about 45 ku as calculated by AlpHaEaseFC~(TM) software and this cellulase was named Cx1. The results of its enzymatic properties using sodium carboxymethylcellulose (CMC) as the substrate showed that its K_m was 0.289 mg/mL and its V_(max) was 0.446 U·mL~(-1)·min~(-1). Its optimum reaction temperature and pH value were 55 ℃ and pH 6.0, respectively. The enzyme was stable over a broad temperature (40-60 ℃) and pH (5.0-8.0) range. Under these conditions, the levels of enzymatic activity could be retained above 55%. Moreover, it was found that the enzyme was dramatically activated by Ag~+ and Ba~(2+), completely inactivated by Cu~(2+) and partially by many other metal ions, such as K~+, Zn~(2+), Mg~(2+), Ca~(2+), NH~+_4, Ni~(2+), Na~+ and Pb~(2+), while Fe~(2+) showed no effect on the reaction.