Bleomycin-induced gene expression in E.coli carrying blmA gene

博莱霉素诱导携带 blmA 基因的大肠杆菌中的基因表达

基本信息

批准号：
05454570
负责人：
SUGIYAMA Masanori
金额：
$ 4.42万
依托单位：
HIROSIMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1994
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05454570/
关键词：
Bleomycim Inducer beta-lactamase Antitumor agent インデューサー

项目摘要

A bleomycin (Bm)-producing microorganism, Streptomyces verticillus ATCC15003 possesses two Bm resistance genes designated blmA and blmB.When one of these genes, designatedblmA,was inserted into pUC18 (or pUC19) plasmid and introduced into Escherichia coli TG1, the transformed cells expressed high level-resistance to Bm. In the present study we show that E.coli harboring the blmA-encoding pUC vector overproduced a 30-kDa protein when cultured in the presence of Bm. The Bm-induced protein was identified as the beta-lactamase encoded by the ampicillin resistance gene on the plasmid. In addition, we found that although the Bm family such as pepleomycin, phleomycin, cleomycin and liblomycin gave rise to beta-lactamase induction, bleomycininc acid which lacks terminal amine moiety in Bm molecule, did scarcely. We propose a hypothesis that Bm, an antibiotic inhibitor of DNA synthesis, acts as a an inducer (or an activator) for the expression of a specific gene in the presence of blmA.On the other hand, we constructed a chimeric plasmid designatd as intelligent vector pMAB70, which carried blmA and a tyrosinase structual gene put under the control of beta-lactamase promoter. E.coli harboring pMAB70 produced the melanine pigment, when cultured in the presence of Bm.

A bleomycin (Bm)-producing microorganism, Streptomyces verticillus ATCC15003 possesses two Bm resistance genes designated blmA and blmB.When one of these genes, designatedblmA,was inserted into pUC18 (or pUC19) plasmid and introduced into Escherichia coli TG1, the transformed cells expressed对BM的高级抗性。在本研究中，我们表明，携带BLMA编码的PUC载体的大肠杆菌在存在BM的情况下培养时产生了30 kDa蛋白。 BM诱导的蛋白被鉴定为质粒上的氨苄西林耐药基因编码的β-内酰胺酶。此外，我们发现，尽管BM家族（例如胸腺霉素，羊霉素，克霉素和liblomycin）产生了β-内酰胺酶诱导，但在BM分子中缺乏末期胺基部分的bleymycininc酸会产生。我们提出了一个假设，即DNA合成的抗生素抑制剂BM充当诱导剂（或激活剂），用于在Blma.ONE的存在下表达特定基因的表达，我们在另一只方面构建了一种智能质粒设计载体PMAB70，它携带BLMA和酪氨酸酶结构基因置于β-内酰胺酶启动子的控制之下。当在BM存在下培养时，携带PMAB70的大肠杆菌产生了黑色素色素。