Surya Sukumaran, Haridas Madhathilkovilakathu
Inter University Centre for Bioscience and Department of Biotechnology and Microbiology, Kannur University, Thalassery Campus, Kannur 670661, India.
Iran J Biotechnol. 2018 Dec 12;16(4):e1449. doi: 10.21859/ijb.1449. eCollection 2018 Dec.
The ethno-medical significance of genus raises the interest towards the characterization of its seed lectin by inexpensive and most effective technique.
The focus of this study is the purification, characterization, and evaluation of the antioxidant and antiproliferative potential of a galactose-specific lectin from L. seeds.
The crude extract, homogenized in 6 volumes of the saline containing 10 mM β-mercaptoethanol was subjected to pigment removal by Toyopeal HW-55 column prior to ammonium sulfate fractionation (40-80 %). The crude protein extract was then loaded to the gel filtration column Sephadex G-200 followed by affinity chromatography using activated galactose coupled Sepharose-4B.
The SDS-PAGE analysis showed a single band of about 30 kDa which further determined by MALDI-TOF analysis. The MALDI-TOF spectra revealed that Clerodendrum infortunatum lectin (CIL) is a homo-tetramer of 120 kDa consisting of four identical subunits of 30 kDa. The haemagglutination inhibition assay was done with purified lectin by many sugars, among which N-acetyl-D-galactosmine (NAG), D-galactose and lactose exhibited high inhibition. NAG showed the highest inhibition amongst the tested sugars, having the minimum inhibitory concentration of about 0.97 mM. The lectin exhibited a moderate antioxidant activity with an IC value of 6.1 ± 0.1 mg.mL and induced cell death with IC of 82.8 μg.mL against human gastric cancer cell line, AGS, indicated the potential of CIL for clinical and therapeutic applications.
The present study demonstrated the moderate ability of the CIL to inhibit the growth of human gastric cancer cells, AGS either by causing cytotoxic or anti-proliferative effects. Thus, CIL due to its remarkable properties may be considered as a potential bio-molecule in tumor research and glycobiology.
该属植物的民族医学意义引发了人们对采用廉价且高效的技术来表征其种子凝集素的兴趣。
本研究的重点是对来自[植物名称]种子的半乳糖特异性凝集素进行纯化、表征，并评估其抗氧化和抗增殖潜力。
将粗提物在含有10 mM β-巯基乙醇的6倍体积盐溶液中匀浆，在硫酸铵分级分离（40 - 80%）之前，通过Toyopeal HW - 55柱去除色素。然后将粗蛋白提取物加载到Sephadex G - 200凝胶过滤柱上，接着使用活化半乳糖偶联的Sepharose - 4B进行亲和色谱。
SDS - PAGE分析显示一条约30 kDa的单一带，通过MALDI - TOF分析进一步确定。MALDI - TOF光谱显示臭牡丹凝集素（CIL）是一种120 kDa的同四聚体，由四个相同的30 kDa亚基组成。用多种糖类对纯化的凝集素进行血凝抑制试验，其中N - 乙酰 - D - 半乳糖胺（NAG）、D - 半乳糖和乳糖表现出高抑制作用。在测试的糖类中，NAG的抑制作用最强，最低抑制浓度约为0.97 mM。该凝集素表现出中等程度的抗氧化活性，IC值为6.1 ± 0.1 mg/mL，对人胃癌细胞系AGS诱导细胞死亡的IC值为82.8 μg/mL，表明CIL在临床和治疗应用方面具有潜力。
本研究表明CIL具有中等程度的抑制人胃癌细胞系AGS生长的能力，可通过引起细胞毒性或抗增殖作用来实现。因此，由于其显著特性，CIL可被视为肿瘤研究和糖生物学中的一种潜在生物分子。
