Rapp P
Institut für Biochemie und Biotechnologie, Technischen Universität Braunschweig, Germany.
Biochim Biophys Acta. 1992 Jul 21;1117(1):7-14. doi: 10.1016/0304-4165(92)90155-n.
The appearance of beta-1,3-glucanases in supernatants of Sclerotium glucanicum cultures was followed by SDS-PAGE and shown to be dependent on cultivation time. Three beta-1,3-glucanases were isolated and purified. Glucanase I and III appeared homogeneous on SDS-PAGE with molecular masses of 85 and 33.5 kDa, respectively. Enzyme I was an endo-splitting beta-1,3-glucanase. In hydrolyzing laminarin it released glucose, laminaritriose and laminaribiose as major endproducts and smaller amounts of higher oligosaccharides. Enzyme III was an exo-beta-1,3-glucanase removing glucose from laminarin and gentiobiose and glucose from scleroglucan. For laminarin as substrate the Km of enzyme I and III was 2.5 and 3.33 mg/ml, respectively. Enzyme II was only partially purified and found to be also an exo-beta-1,3-glucanase, releasing glucose as the only hydrolysis product from laminarin. It did not attack scleroglucan. Its molecular weight was determined to be 78 kDa. Optimum pH and temperature of the three enzymes were determined. The three activities were significantly inhibited by 1 mM Hg2+.
通过SDS - PAGE追踪葡聚糖核盘菌培养上清液中β-1,3-葡聚糖酶的出现情况，并表明其依赖于培养时间。分离并纯化了三种β-1,3-葡聚糖酶。葡聚糖酶I和III在SDS - PAGE上呈现均一性，分子量分别为85 kDa和33.5 kDa。酶I是一种内切型β-1,3-葡聚糖酶。在水解海带多糖时，它释放出葡萄糖、海带三糖和海带二糖作为主要终产物以及少量更高的寡糖。酶III是一种外切β-1,3-葡聚糖酶，从海带多糖中去除葡萄糖，从硬葡聚糖中去除龙胆二糖和葡萄糖。以海带多糖为底物时，酶I和III的Km分别为2.5和3.33 mg/ml。酶II仅部分纯化，发现也是一种外切β-1,3-葡聚糖酶，从海带多糖中释放葡萄糖作为唯一的水解产物。它不作用于硬葡聚糖。其分子量测定为78 kDa。测定了这三种酶的最适pH和温度。这三种酶的活性均被1 mM Hg2+显著抑制。
