Subha Mahadevi A, Vegiraju Suryanarayana R, Siva Kumar N
Department of Biochemistry, University of Hyderabad, India.
J Biochem Mol Biol Biophys. 2002 Dec;6(6):397-400. doi: 10.1080/1025814021000036133.
Seeds of Triticale (hybrid of wheat and rye) contain an N-acetylglucosamine specific lectin that was affinity purified in our laboratory (Siva Kumar, N. and Padma, K. (1996) "Affinity purification of N-acetyl glucosamine specific lectin. Purification and partial characterization of Triticale lectin". Biochem. Mol. Biol. Int. 38, 1059-1066). Seed extracts also exhibited alpha-mannosidase activity that was isolated by a combination of ion exchange, hydrophobic chromatography and gel filtration. The purified enzyme is a glycoprotein with 7% carbohydrate and exhibited a native molecular mass of 1,95,000 (+/-5000) on Biogel P-200 and dissociated into two major subunits under reducing conditions of molecular masses 58 and 40 kDa, respectively. Both subunits cross-reacted with an antibody to the well-characterized jack bean alpha-mannosidase, suggesting antigenic similarity between the legume and the cereal mannosidases. Purified enzyme binds to Con A-Sepharose gel, possibly through the sugar-binding site. Purified Triticale enzyme was stable at 50 degrees C up to 20 min and did not show requirement of metal ions for activity. Phenylalanine was detected as the sole N-terminal amino acid in the purified enzyme.
小黑麦（小麦和黑麦的杂交种）种子含有一种N - 乙酰葡糖胺特异性凝集素，该凝集素在我们实验室进行了亲和纯化（西瓦·库马尔，N. 和帕德玛，K.（1996年）“N - 乙酰葡糖胺特异性凝集素的亲和纯化。小黑麦凝集素的纯化及部分特性鉴定”。《生物化学与分子生物学国际杂志》38卷，第1059 - 1066页）。种子提取物还表现出α - 甘露糖苷酶活性，该活性通过离子交换、疏水色谱和凝胶过滤相结合的方法进行分离。纯化后的酶是一种糖蛋白，碳水化合物含量为7%，在Biogel P - 200上显示出天然分子量为195,000（±5000），在还原条件下解离为两个主要亚基，分子量分别为58 kDa和40 kDa。两个亚基都与针对特性明确的刀豆α - 甘露糖苷酶的抗体发生交叉反应，表明豆科植物和谷物甘露糖苷酶之间存在抗原相似性。纯化后的酶可能通过糖结合位点与伴刀豆球蛋白A - 琼脂糖凝胶结合。纯化后的小黑麦酶在50℃下稳定20分钟，且活性不需要金属离子。在纯化后的酶中检测到苯丙氨酸是唯一的N - 末端氨基酸。
