PeliCRM CRM197 白喉毒素突变体是一种使用Pelican Expression Technology平台在荧光假单胞菌中表达的重组形式。CRM197 白喉毒素突变体是结合疫苗的理想载体蛋白或免疫佐剂。通过物理化学特性和体内研究表明，PeliCRM197 白喉毒素突变体在结构和功能上与白喉棒状杆菌产生的突变蛋白相同。目前的研究和开发领域包括免疫疗法和抗成瘾性疫苗。可提供满足任何临床研究或商业化生产要求的研究等级或者cGMP等级的规格。自1990年以来，CRM197 白喉毒素突变体已被商业应用于预防性疫苗中。
（3） 重组CRM197（bulk）产品是根据现行cGMP生产规范和ICH Q7和ICH Q11（视情况而定）指导原则制造的，重组CRM197（bulk）作为活性物质起始材料，用于最终用户进一步制造合适的原料药和/或药品。
使用前，用无菌去离子水将冻干的PeliCRM197无菌复原至4 mg/mL的浓度 。
产品分子量: 58.4 kDa
纯度：>95% PeliCRM197 by SE-HPLC or RP-HPLC or SDS-PAGE
内毒素: <100 EU/mg of protein by LAL method
1. Giannini, G., Rappuoli, R., and Ratti, G. Nucleic Acids Res. 12: 4063-4069 (1984)
2. Mekada, E., and Uchida, T. J. Biol. Chem. 260: 12148-12153 (1985)
The amino-acid sequence of two non-toxic mutants of diphtheria toxin: CRM45 and CRM197.
Nucleic Acids Research | By G Giannini, R Rappuoli, and G Ratti | May 25, 1984
Abstract: The amino-acid sequences of two diphtheria toxin-related, non-toxic proteins, CRM45 and CRM197 , were deduced from the complete sequence of their genes: tox 45 and tox 197. CRM45 lacks the last 149 C-terminal amino-acid residues, but is otherwise identical to diphtheria toxin: a single C—-T transition introduces an “ochre” (TAA) termination signal in tox 45, after the codon for threonine-386. A single G—-A transition was also found in tox 197, leading to the substitution of glycine-52, present in the wild-type toxin, with glutamic acid in CRM197 . This aminoacid change is responsible for the loss of the NAD:EF2 ADP-ribosyltransferase activity in CRM197 , due most probably to an alteration of the NAD+ binding site.
Identification of diphtheria toxin receptor and a nonproteinous diphtheria toxin-binding molecule in Vero cell membrane
Journal of Cell Biology | By: Mekada, E., and Uchida, T. J. | August 1, 1988
Abstract: Two substances possessing the ability to bind to diphtheria toxin (DT) were found to be present in a membrane fraction from DT-sensitive Vero cells. One of these substances was found on the basis of its ability to bind DT and inhibit its cytotoxic effect. This inhibitory substance competitively inhibited the binding of DT to Vero cells. However this inhibitor could not bind to CRM197, the product of a missense mutation in the DT gene, and did not inhibit the binding of CRM197 to Vero cells. Moreover, similar levels of the inhibitory activity were observed in membrane fractions from DT-insensitive mouse cells, suggesting the inhibitor is not the DT receptor which is specifically present in DT-sensitive cells. The second DT-binding substance was found in the same Vero cell membrane preparation by assaying the binding of 125I-labeled CRM197. Such DT-binding activity could not be observed in membrane preparation from mouse L cells. From competition studies using labeled DT and CRM proteins, we conclude that this binding activity is due to the surface receptor for DT. Treatment of these substances with several enzymes revealed that the inhibitor was sensitive to certain RNases but resistant to proteases, whereas the DT receptor was resistant to RNase but sensitive to proteases. The receptor was solubilized and partially purified by chromatography on CM- Sepharose column. Immunoprecipitation and Western blotting analysis of the partially purified receptor revealed that a 14.5-kD protein is the DT receptor, or at least a component of it.