从南非多瘤海葵 Bunodosoma capense 分泌的一种假定钠离子通道激动剂的纯化和生化特性。
Purification and biochemical characterisation of a putative sodium channel agonist secreted from the South African Knobbly sea anemone Bunodosoma capense.
机构信息
Department of Biochemistry and Microbiology, Nelson Mandela University, Port Elizabeth, South Africa.
Department of Zoology, Ocean Sciences Campus, Nelson Mandela University, Port Elizabeth, South Africa; South African Environmental Observation Network, Elwandle Coastal Node, Ocean Sciences Campus, Nelson Mandela University, South Africa.
出版信息
Toxicon. 2019 Oct;168:147-157. doi: 10.1016/j.toxicon.2019.06.222. Epub 2019 Jul 19.
Voltage gated ion channels have become a subject of investigation as possible pharmaceutical targets. Research has linked the activity of ion channels directly to anti-inflammatory pathways, energy homeostasis, cancer proliferation and painful diabetic neuropathy. Sea anemones secrete a diverse array of bioactive compounds including potassium and sodium channel toxins. A putative novel sodium channel agonist (molecular mass of 4619.7 Da) with a predicted sequence: CLCNSDGPSV RGNTLSGILW LAGCPSGWHN CKKHKPTIGW CCK was isolated from Bunodosoma capense using a modified stimulation technique to induce the secretion of the neurotoxin rich mucus confirmed by an Artemia nauplii bio-assay. The peptide purification combined size-exclusion and reverse-phase high performance liquid chromatography. A thallium-based ion flux assay confirmed the presence of a sodium channel agonist/inhibitor and purity was determined using a modified tricine SDS-PAGE system. The peptide isolated indicated the presence of multiple disulfide bonds in a tight β-defensin cystine conformation. An IC value of 26 nM was determined for total channel inhibition on MCF-7 cells. The unique putative sodium channel agonist initiating with a cystine bond indicates a divergent evolution to those previously isolated from Bunodosoma species.
电压门控离子通道已成为研究的课题，因为它们可能成为药物靶点。研究表明，离子通道的活性与抗炎途径、能量平衡、癌症增殖和糖尿病性神经病变直接相关。海葵分泌多种具有生物活性的化合物，包括钾离子和钠离子通道毒素。从 Bunodosoma capense 中分离出一种新型的钠通道激动剂（分子量为 4619.7 Da），其预测序列为：CLCNSDGPSV RGNTLSGILW LAGCPSGWHN CKKHKPTIGW CCK，采用改良的刺激技术诱导富含神经毒素的粘液分泌，该技术通过卤虫幼虫生物测定得到证实。肽的纯化结合了分子筛和反相高效液相色谱。基于铊的离子通量测定法证实了钠离子通道激动剂/抑制剂的存在，并且使用改良的 tricine SDS-PAGE 系统确定了纯度。分离出的肽表明存在多个二硫键，形成紧密的β-防御素半胱氨酸构象。对 MCF-7 细胞进行的总通道抑制实验得出的 IC 值为 26 nM。该独特的假定的钠通道激动剂以半胱氨酸键起始，表明其与先前从 Bunodosoma 属中分离出的钠通道激动剂具有不同的进化。
Zotero 插件