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現(xiàn)貨供應(yīng)Gibco公司G418產(chǎn)品

產(chǎn)品介紹：

G418（G-418即G-418 sulfate，也稱(chēng)Geneticin，分子式為C20H40N4O10.2H2SO4，分子量為692.71 g/mole）是一種氨基糖類(lèi)抗生素，其結(jié)構(gòu)與新霉素、慶大霉素、卡那霉素相似，它通過(guò)影響80S核糖體功能而阻斷蛋白質(zhì)合成,對(duì)原核和真核等細(xì)胞都有毒性 ,包括細(xì)菌、酵母、植物和哺乳動(dòng)物細(xì)胞 ,也包括原生動(dòng)物和蠕蟲(chóng)。是穩(wěn)定轉(zhuǎn)染zui常用的選擇試劑。當(dāng)neo基因被整合進(jìn)真核細(xì)胞基因組合適的地方后 ,則能啟動(dòng)neo基因編碼的序列轉(zhuǎn)錄為mRNA,從而獲得抗性產(chǎn)物氨基糖苷磷酸轉(zhuǎn)移酶的高效表達(dá) ,使細(xì)胞獲得抗性而能在含有Ｇ418的選擇性培養(yǎng)基中生長(zhǎng)。Ｇ418的這一選擇特性 ,已在基因轉(zhuǎn)移、基因敲除、抗性篩選以及轉(zhuǎn)基因動(dòng)物等方面得以廣泛應(yīng)用。
        G418和篩選
        篩選之前由于每種細(xì)胞對(duì)G418的敏感性不同，而且不同的廠家生產(chǎn)的相同濃度的G418的活性不盡相同，所以在篩選之前，一定要確定G418的*篩選濃度。具體如下：將細(xì)胞稀釋到1000個(gè)細(xì)胞/mL，在100ug/mL~1mg/mL的G418濃度范圍內(nèi)進(jìn)行篩選，選擇出在10~14天內(nèi)使細(xì)胞全部死亡的zui低G418濃度來(lái)進(jìn)行下一步的篩選試驗(yàn)。
        由于每種細(xì)胞對(duì)G418的敏感性不同，一般變動(dòng)在100ug/ml～1000ug/ml范圍。而且不同的廠家生產(chǎn)的相同濃度的G418的活性不盡相同，所以在篩選之前，一定要確定你的細(xì)胞對(duì)這一批G418的*篩選濃度。盡管如此，特性明確的細(xì)胞系G418的*用量還是穩(wěn)定的?！斗肿涌寺　方o出了幾個(gè)常用細(xì)胞系所需G418的*用量：

訂購(gòu)信息：

我公司提供的G418來(lái)自Gibco公司，技術(shù)參數(shù)如下：
Shipping Conditions（運(yùn)輸條件）
GENETICIN is shipped at ambient temperature.
Storage Conditions（儲(chǔ)存環(huán)境）
GENETICIN should be stored at room temperature, 15 to 30°C. GENETICIN is soluble in water and should be stored at 2 to 8°C as a solution.
Background
GENETICIN is an aminoglycoside related to Gentamicin and is used as a selective agent in molecular genetics experiments. It is toxic to both prokaryotic and eukaryotic cells. The resistance genes are dominant and are located on both Transposons Tn601 （903） and Tn5. The gene on Tn5 is referred to as a aminoglycoside phosphotransferase 3' （I） or APH（3'）I.The genes are bacterial in derivation but they can be expressed in eukaryotic cells. Efficient expression is achieved when the neo DNA sequence is linked to eukaryotic DNA sequences that permit transcription and processing of the Neo coding sequence into mRNA. Introduction of either of these genes into cells can confer resistance to GENETICIN, enabling the cells to grow in media containing GENETICIN. 
Description
GENETICIN is also known as Antibiotic G-418 Sulfate. GENETICIN is supplied
as a white powder. The amount of GENETICIN required to be present in culture media to select for resistant cells varies with a number of factors including cell type. Good laboratory practice requires that the optimal concentration of GENETICIN required to maintain and select cells must be determined for each set of growth conditions. Invitrogen recommends that whenever experimental conditions are altered （including use of GENETICIN from a different lot）, the optimal concentration of the product be re-evaluated.
Quality Control
Absorbance - Visible range: At a concentration of 100 mg/mL in water, GENETICIN gives a clear colorless solution. The absorbance of this solution at 400 nm is less than 0.075 O.D.
Absorbance - Ultraviolet range: At a concentration of 1 mg/mL in water, the absorbance at 280 nm is less than 0.015 O.D.