霍亂毒素（Cholera Toxins，CTX）
同義名：
Cholera enterotoxin; Choleragen; 霍亂腸毒素；霍亂腸菌素；
搜索關聯詞：
霍亂毒素（Cholera toxin）； 霍亂類毒素Choleragenoid；霍亂毒素B亞基（CTB）；霍亂毒素B亞單位；腺苷酸環化酶（Adenylate cyclase，AC）；Forskolin 佛司可林；
基本介紹：
霍亂毒素（Cholera toxin，CTX）是霍亂弧菌產生的毒力因子，會引起嚴重腹瀉以及人體脫水。CTX是一種分子量約84kDa的寡蛋白，包含一個A亞基以及包圍在周圍的5個B亞基構成。CTX是一種有效的腺苷酸環化酶（Adenylate cyclase，AC）活化劑，也是負責霍亂癥狀的病原物質。霍亂毒素B亞基（a.k.a. 霍亂類毒素choleragenoid）負責全毒素識別并結合到哺乳動物細胞表面的GM1神經節苷脂受體，促進A亞基進入細胞；A亞基承擔ADP核糖轉移酶（ADP-ribosyl-transferase）活性，此酶能下調Gs蛋白表達并活化AC酶，進而促進cAMP水平提高。A亞基還能ADP核糖基化視桿細胞外節膜盤的轉運蛋白，使得GTPase失活。歸因于GM1神經節苷脂受體普遍存在于真核細胞膜上，CTX用于各種各樣的模型系統中活化腺苷酸環化酶（AC）。CTX還是一種的黏膜疫苗佐劑，通過抑制IL-12生產來誘導2型輔助性T細胞的免疫應答。
生理功能：
霍亂毒素（Cholera toxin，CTX）由霍亂弧菌（Vibrio cholerae）代謝純化所得，不僅在微生物學是一種強大的研究工具，還普遍用于生理學、細胞生物學和生物化學。常見應用如下：
1）因其對腺苷酸環化酶（AC）的效應，CTX通常用來研究信號轉導機制。
2）CTX通過刺激B淋巴細胞活性用作一種佐劑；（與疫苗佐劑的開發有關，CTX有效調節哺乳動物細胞免疫系統，用作一種聯合抗原共同注射的佐劑）
3）純化的霍亂毒素B亞基（Cholera toxin B subunit）用于神經研究方面的神經示蹤，利用其GM1 神經節苷脂結合和逆行轉運特點。
基本參數：
1）CAS NO：9012-63-9
2）純度：>95%（When examined by polyacrylamide gel electrophoresis in a non-denaturing system run at alkaline pH, this protein migrates as a single major band. When examined on SDS-PAGE, all subunits, A, A1, A2, and B, are present. Densitometric analysis estimates the purity as >95%. The 280 to 260 nm ratio of absorbance (R280/260) is 2.
3）內毒素：~5 EU/mg (determined using a kinetic chromogenic LAL assay)
4）生物活性：Hemagglutination activity is assessed with trisialoganglioside fixed sheep red blood cells using a modification of the method described by Sato, et al. This lot met the specification of exhibiting hemagglutination activity at a toxin dilution ≤1.6µg/ml.
產品信息
List labs提供凍干粉形式的霍亂毒素（Cholera Toxin，CTX，CT）和霍亂毒素B亞基，所有產品經過內毒素去除和無菌處理。并經過嚴格的純度和生物活性檢測，是高質量的研究工具。部分現貨供應，*，咨詢maokangbio。
品牌 | 產品名稱 | 貨號 | 規格 |
List Biological laboratories | Cholera Toxin from Vibrio cholerae | 101B | 1mg |
Cholera Toxin (AZIDE-FREE) from Vibrio cholerae | 100B | 1mg | |
Cholera Toxin B Subunit (Choleragenoid) from Vibrio cholerae | 103B | 1mg | |
Cholera Toxin B Subunit (Choleragenoid) from Vibrio cholerae in Low Salt | 104 | 0.5mg |
延伸產品：部分現貨供應，*，咨詢maokangbio。
品牌 | 產品名稱 | 貨號 | 規格 |
List Biological laboratories | Cholera Toxin B Subunit (CTB) from Vibrio cholerae FITC, Conjugate | 106 | 0.2mg |
Cholera Toxin B Subunit Biotin Conjugate | 112 | 0.2mg | |
Anti-Cholera Toxin B Subunit (Goat) | 703 | 0.1ml |
【應用說明】：
1）霍亂毒素B亞基（CTB）偶聯物用于軸漿運輸和神經元連接研究中的組織化學標志物（histochemical markers）。
2）Goat Anti-Cholera Toxin B Subunit (Choleragenoid)適用于中和（Neutralization）和結合實驗，或與未標記霍亂毒素B亞基聯合的免疫組化研究。
引用文獻【List Biological】
Wu J et al. Hydrogen postconditioning promotes survival of rat retinal ganglion cells against ischemia/reperfusion injury through the PI3K/Akt pathway. Biochem Biophys Res Commun. 2018 Jan 22;495(4):2462-2468. PubMed ID: 29288664 [Retinal ganglion cells (RGCs)density was counted using haematoxylin and eosin (HE) staining, retrograde labelling with cholera toxin beta (CTB) and TUNEL staining, respectively. List Biological Cholera Toxin B Subunit (CTB) from Vibrio cholerae FITC, Conjugate (#106)]
Aoki S et al. Multizonal Cerebellar Influence Over Sensorimotor Areas of the Rat Cerebral Cortex. Cereb Cortex. 2017 Dec 29. PMID: 29300895 [Under visual guidance, viral solution containing the French subtype of CVS-11 strain of RABV (titrating 4 × 107 plaque-forming units/ml) in conjunction with cholera toxin β-subunit (CTb, low salt; List Biological Laboratories, 1% w/v in 0.2 M phosphate buffer. List Biological Cholera Toxin B Subunit (Choleragenoid) from Vibrio cholerae in Low Salt (#104) ]
Dong L et al. Calcium channels are involved in EphB/ephrinB reverse signaling?induced apoptosis in a rat chronic ocular hypertension model. Mol Med Rep. 2018 Feb;17(2):2465-2471. PMID: 29207174 [Retinal sections were then blocked for 2 h in 6% normal donkey serum, 1% bovine serum, and 0.2% Triton X-100, and dissolved in PBS at room temperature. Consequently, sections were incubated with the following primary antibodies at 4°C for 24 h: polyclonal rat anti-Cav3.1, anti-Cav3.2, (1:200 dilution; Alomone Labs, Jerusalem, Israel), Goat anti-CTB (cat. no. 703; List Biological Laboratories)]
Konno K et al. Cell-type specific parallel circuits in the bed nucleus of the stria terminalis and the cenral nucleus of the amygdala of the mouse. J Neurosci. 2014 May 28;34(22):7412-24. PMID: 24872547 [CTb Goat, antiserum 1:3000 choleragenoid Cat. #703, List Biological Laboritories]
Lu X et al. Effects of 1,25 and 24,25 Vitamin D on Corneal Epithelial Proliferation, Migration and Vitamin D Metabolizing and Catabolizing Enzymes. Sci Rep. 2017 Dec 5;7(1):16951.PMID: 29208972 [Each cornea was cut in half and placed in a 35 mm dish with the epithelial side up. After approximay 5 minutes in the laminar air-flow culture hood, the half corneal button attached itself to the bottom of the plate, and 1.5 mL of DMEM with 10% serum containing 40 μg/mL gentamicin, 1% ITS, and100 ng/mLcholera toxin(LIST Biological Laboratories, Inc., Campbell, CA) were added and the tissue was placed in a humidified incubator at 37 °C with 5% CO2. Culture medium was replaced every 2 days.]
Bruxelle JF et al. Clostridium difficile flagellin FliC: Evaluation as adjuvant and use in a mucosal vaccine against Clostridium difficile. PLoS One. 2017 Nov 27;12(11):e0187212. PMID: 29176760 [Vaccination regimen with ovalbumin as antigen: Ovalbumine (OVA) is a commonly used antigen in order to assess adjuvant activity. In two distinct assays, a total of fourteen mice per group received inra-rectally (IR) 20μg of ovalbumin (ovalbumin grade VII, Sigma) with 7μg of adjuvant, either cholera toxin (CT) (List Biological Laboratories, INC)]
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— —Written/Edited by V. Shallan【版權歸MKBio懋康所有】
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