Indra D, Ganesh S, Ramalingam K, Asokan C, Jayakumar R
PG and Research Department of Zoology, Government Arts College, Nandanam, Chennai, India.
Comp Biochem Physiol C Toxicol Pharmacol. 2000 Sep;127(2):177-83. doi: 10.1016/s0742-8413(00)00148-1.
9-O-Acetyl neuraminic acid specific lectin (AchatininH) was isolated from the hemolymph of the land snail Achatina fulica by affinity chromatography on sheep submaxillary mucin (SSM) coupled cyanogen bromide activated Sepharose 4B. The molecular weight of the native protein was 2.42 kDa. UV-Vis absorption, fluorescence and circular dichroism spectroscopic studies on AchatininH revealed the importance of divalent metal ions (Ca2 +, Mg2+ and Mn2+) on lectin conformational change associated with activity of lectins. The binding of these cations changes lambdamax to shorter wavelength in the far UV region (blue shift) and longer wavelength in UV region (red shift), indicating substantial contribution of aromatic side chain in the far UV region on binding with metal ions. The results infer that divalent cations cause conformational changes in lectin which may be responsible for affinity with their carbohydrate moiety.
通过在偶联了溴化氰活化琼脂糖4B的绵羊下颌粘蛋白（SSM）上进行亲和层析，从褐云玛瑙螺的血淋巴中分离出9-O-乙酰神经氨酸特异性凝集素（玛瑙螺凝集素H）。天然蛋白的分子量为2.42 kDa。对玛瑙螺凝集素H进行紫外-可见吸收、荧光和圆二色光谱研究，揭示了二价金属离子（Ca2 +、Mg2+和Mn2+）对与凝集素活性相关的凝集素构象变化的重要性。这些阳离子的结合使远紫外区的最大波长向更短波长变化（蓝移），紫外区的最大波长向更长波长变化（红移），表明在远紫外区芳香侧链与金属离子结合中起重要作用。结果推断二价阳离子会引起凝集素的构象变化，这可能是其与碳水化合物部分亲和力的原因。
