Aanangi Raveendra, Kotapati Kasi Viswanath, Palaka Bhagath Kumar, Kedam Thyagaraju, Kanika Nirmala Devi, Ampasala Dinakara Rao
Department of Biochemistry, Sri Venkateswara University, Tirupati, 517 502, Andhra Pradesh, India.
Centre for Bioinformatics, School of Life sciences, Pondicherry University, Puducherry, 605014, India.
3 Biotech. 2016 Jun;6(1):113. doi: 10.1007/s13205-016-0427-5. Epub 2016 May 17.
This study reports purification and characterization of lipoxygenase protein from mung bean germinating seedlings. Lipoxygenases (LOXs) are key enzymes in seed germination. The purified mung bean LOX has resolved into two peaks by chromatofocusing, one has highest LOX activity with an isoelectric point of 5.84 and the other has lowest LOX activity with an isoelectric point of 5.52. The purified LOX has molecular mass of approximately 97 kDa and showed high activity with linoleic acid than linolenic acid and arachidonic acid. The optimal activity of LOX was observed at pH 6.5 and temperature 35 °C. Far-UV circular dichroism (CD) studies revealed that the purified mung bean LOX possess secondary structural elements with significant α-helix and β-strands. Further, the secondary structure of mung bean LOX was stable up to 60 °C at pH 6.5. Biophysical and chemical properties of the mung bean LOX are similar to the other legume LOXs and may be considered as type-1 LOX.
本研究报道了从绿豆发芽幼苗中纯化和鉴定脂氧合酶蛋白的过程。脂氧合酶（LOXs）是种子萌发中的关键酶。通过色谱聚焦法，纯化后的绿豆脂氧合酶分离为两个峰，一个具有最高的脂氧合酶活性，等电点为5.84，另一个具有最低的脂氧合酶活性，等电点为5.52。纯化后的脂氧合酶分子量约为97 kDa，对亚油酸的活性高于亚麻酸和花生四烯酸。脂氧合酶的最佳活性在pH 6.5和温度35℃时观察到。远紫外圆二色性（CD）研究表明，纯化后的绿豆脂氧合酶具有显著的α-螺旋和β-链二级结构元件。此外，在pH 6.5时，绿豆脂氧合酶的二级结构在60℃以下是稳定的。绿豆脂氧合酶的生物物理和化学性质与其他豆科植物脂氧合酶相似，可被视为1型脂氧合酶。
