Department of Zoology, Holy Cross College (Autonomous), Nagercoil, Affiliated to Manonmaniam Sundaranar University, Tirunelveli, 627 012, Tamil Nadu, India.
Department of Zoology, Holy Cross College (Autonomous), Nagercoil, Affiliated to Manonmaniam Sundaranar University, Tirunelveli, 627 012, Tamil Nadu, India.
Fish Shellfish Immunol. 2023 Oct;141:109001. doi: 10.1016/j.fsi.2023.109001. Epub 2023 Aug 18.
Lectins are non-immune glycoproteins or proteins having a unique capacity to interact with carbohydrate ligands found on the surface of their host cells. In the present investigation, the lectin was purified from the hemolymph of freshwater crab, Oziotelphusa naga and its antimicrobial, anti-inflammatory and anti-arthritic activity was analysed. The preliminary characterization of the hemagglutinin was carried out to identify the erythrocyte and sugar specificity, optimum pH and temperature and cation dependency. The agglutinin was found to be highly specific to rabbit erythrocyte and inhibited by fetuin and α-lactose. Maximum hemagglutination activity was noted at pH 7.5-8 and temperature 20-40 °C. An O-acetyl sialic acid specific 75 kDa hemolymph lectin, designated as NagLec was isolated from the freshwater crab, Oziotelphusa naga by affinity chromatography on fetuin coupled Sepharose 4 B, with a purification fold of 185. The bacteria Staphylococcus aureus, Proteus mirabilis and fungus Candida albicans had the greatest zone of inhibition when treated with NagLec. The results of the Minimum inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) assays showed that the purified lectin inhibited the growth of Staphylococcus aureus at 0.031 and 0.065 μg/ml, which proved the bactericidal property of NagLec. NagLec generated alterations on the bacterial cells and led to protein leakage, which was dosage (24 and 48 μg/ml) and time dependent (10-40 min). COX and LOX enzyme was inhibited to 49.43% and 61.81% with 100 μg/ml concentration of NagLec respectively, demonstrating NagLec's ability to reduce inflammation. Furthermore, NagLec (500 μg) suppressed protein denaturation up to 77.12% whereas diclofenac sodium (a standard drug) was inhibited by 89.36%. The results indicate that NagLec, a sialic acid specific lectin isolated from the freshwater crab O. naga could be formulated as a nano drug in future owing to its antimicrobial, anti-inflammatory and anti-arthritic potential that could be targeted to specific pathogenic microbes and treat arthritis.
凝集素是一种非免疫糖蛋白或具有独特能力与宿主细胞表面碳水化合物配体相互作用的蛋白质。在本研究中，从淡水蟹的血淋巴中纯化了凝集素，并分析了其抗菌、抗炎和抗关节炎活性。对凝集素进行了初步的特征分析，以确定其红细胞和糖的特异性、最佳 pH 值和温度以及阳离子依赖性。该凝集素对兔红细胞具有高度特异性，并被胎球蛋白和α-乳糖抑制。最大的凝集活性在 pH7.5-8 和温度 20-40°C 时观察到。从淡水蟹 Oziotelphusa naga 的血淋巴中分离出一种 O-乙酰神经氨酸特异性 75 kDa 血淋巴凝集素，命名为 NagLec，它通过与胎球蛋白偶联的 Sepharose 4B 亲和层析进行纯化，其纯度提高了 185 倍。当用 NagLec 处理时，细菌金黄色葡萄球菌、奇异变形杆菌和真菌白色念珠菌有最大的抑菌环。最低抑菌浓度（MIC）和最低杀菌浓度（MBC）测定结果表明，纯化的凝集素在 0.031 和 0.065 μg/ml 时抑制金黄色葡萄球菌的生长，这证明了 NagLec 的杀菌特性。NagLec 对细菌细胞产生了改变，导致蛋白质渗漏，这是剂量（24 和 48 μg/ml）和时间（10-40 分钟）依赖性的。NagLec 抑制 COX 和 LOX 酶分别达到 49.43%和 61.81%，浓度为 100 μg/ml，表明 NagLec 具有减轻炎症的能力。此外，NagLec（500 μg）抑制蛋白质变性高达 77.12%，而双氯芬酸钠（一种标准药物）的抑制率为 89.36%。这些结果表明，从淡水蟹 O. naga 中分离出的唾液酸特异性凝集素 NagLec 可以作为一种纳米药物在未来进行开发，因为它具有抗菌、抗炎和抗关节炎的潜力，可以针对特定的致病微生物，并治疗关节炎。
