9012-63-9
中文名稱
霍亂毒素
英文名稱
CHOLERA TOXIN
CAS
9012-63-9
分子式
NULL
更新日期
2026/04/13 08:58:25
基本信息
中文別名
霍亂毒素霍亂菌素
英文別名
Cholergencholeragen
CHOLERA TOXIN
Choleragenoid
choleraexotoxin
exo-enterotoxin
Toxins, cholera
CHOLERA ENTEROTOXIN
VIBRIO CHOLERAE TOXIN
choleraentero-exotoxin
所屬類別
生物化工：霍亂毒素B亞單位安全數(shù)據(jù)
警示詞危險
危險性描述H300+H310-H332-H412
危險品標志T
危險類別碼24/25-52/53
安全說明36/37-45-61
危險品運輸編號3172
WGK Germany2
RTECS號LF3100000
危險等級6.1
包裝類別I
毒性cholera toxin is secreted
by the gram-negative bacterium Vibrio cholerae. It is a gastrointestinal
toxin that increases adenylate cyclase activity of mucosa
of the small intestine, thereby increasing cyclic AMP within
these cells. Cyclic AMP stimulates active transport of ions by
these epithelial cells, resulting in a large efflux of Na+ and water
into the gut. The toxin enters cells by interacting with a GM1
ganglioside on the cell surface. After entry, the A1 subunit catalyzes
the transfer of an ADP-ribose unit from NAD+ to an arginine
side chain of the adenylate cyclase regulatory G protein,
blocking its GTPase activity. Thus the adenylate cyclase deactivation
mechanism is destroyed, and cyclic AMP is continually
produced. The major sign of cholera poisoning is severe diarrhea;
several liters of body water may be lost within a few hours,
leading to shock and death if fluid is not replaced. Treatment
involves physiological support (including i.v. fluids) and antibiotics.
常見問題列表
簡介
霍亂毒素是由霍亂弧菌分泌的一種蛋白質(zhì)復合物，是霍亂弧菌引起嚴重疾病所必需的。組成
霍亂毒素由（Cholera toxin,CT）兩個亞單位組成，即A亞單位（CTA）和B亞單位（CTB）。A亞單位是霍亂毒素的活性部分，B亞單位的主要功能是通過與哺乳動物小腸上皮細胞上的單唾液酸神經(jīng)節(jié)苷脂GM1結(jié)合而使得A亞單位進入細胞。5個CTB與1個CTA以氫鍵和鹽橋連接在一起，形成緊湊而穩(wěn)定的AB5圓筒狀六聚體蛋白。霍亂毒素被認為是最有效的口服免疫原之一?？诜﨏T不但可以使機體產(chǎn)生針對CT的免疫反應，而且可以增強與CT同時給予的其他抗原的免疫反應。作用機制
霍亂毒素可以增強腸粘膜的通透性，從而增加抗原的攝入量；
選擇性誘導以Th2為主的免疫反應，從而增加特異性黏膜IgA抗體的產(chǎn)生；
可誘導IL-4和IL-5顯著提高，而IL-2和IFN-gamma水平無明顯變化。
生物活性
Cholera toxin (Choleragen) 是一種AB(5) 亞單位毒素，通過結(jié)合質(zhì)膜上的神經(jīng)節(jié)苷脂 GM1 進入宿主細胞，并通過跨高爾基體網(wǎng)絡逆行進入內(nèi)質(zhì)網(wǎng)。Choleragen 通過催化促鳥嘌呤核苷酸結(jié)合蛋白 Gsα 的 ADP 核糖基化激活腺苷酸環(huán)化酶 (adenylate cyclase)。體外研究
In the ER, a portion of Cholera toxin, the enzymatic A1-chain, is unfolded by protein disulfide isomerase and retro-translocated to the cytosol by hijacking components of the ER associated degradation pathway for misfolded proteins.
Cholera toxin acts as an ADP-ribosyltransferase to disrupt intracellular signaling in the target cell. Cholera toxin moves by vesicle carriers from the cell surface to the endoplasmic reticulum (ER) of an intoxicated cell.