Bacterial nitroreductase for the reduction of CB 1954 and analogues thereof to a cytotoxic form
申请人:CANCER RESEARCH CAMPAIGN TECHNOLOGY LIMITED
公开号:EP0540263A1
公开(公告)日:1993-05-05
The invention provides a nitroreductase, obtainable from a bacterium having the following characteristics as exemplified by examples isolated from Escherichia coli B and Bacillus amyloliquifaciens:
1. It is a flavoprotein having a molecular weight in the range 20-60 Kilodaltons;
2. It requires either NADH or NAD(P)H or analogues thereof as a cofactor;
3. It has a Km for NADH or NAD(P)H in the range 1-100µM; and
4. It is capable of reducing either or both nitro groups of CB 1954 and analogues thereof to a cytotoxic form e.g. the hydroxylamine.
The sequence of one such nitroreductase is shown in Seq. ID No.1. The nitroreductase may be conjugated to a tumor targeting agent such as a monoclonal antibody and used to convert prodrugs into active antitumour agents. Such prodrugs and drugs are also provided.
本发明提供了一种硝基还原酶,可从具有以下特征的细菌中获得,例如从大肠杆菌 B 和淀粉芽孢杆菌中分离的实例:
1.它是一种黄素蛋白,分子量在 20-60 千道尔顿之间;
2.2. 它需要 NADH 或 NAD(P)H 或其类似物作为辅助因子;
3.它对 NADH 或 NAD(P)H 的 Km 值在 1-100µM 之间;以及
4.4. 它能够将 CB 1954 及其类似物的一个或两个硝基还原成具有细胞毒性的形式,如羟胺。
其中一种硝基还原酶的序列如 Seq.ID No.1。硝基还原酶可与单克隆抗体等肿瘤靶向药结合,用于将原药转化为活性抗肿瘤药。还提供了此类原药和药物。