AUTOREGULATION OF PURR REPRESSOR SYNTHESIS AND INVOLVEMENT OF PURR IN THE REGULATION OF PURB, PURC, PURL, PURMN AND GUABA EXPRESSION IN ESCHERICHIA-COLI
AUTOREGULATION OF PURR REPRESSOR SYNTHESIS AND INVOLVEMENT OF PURR IN THE REGULATION OF PURB, PURC, PURL, PURMN AND GUABA EXPRESSION IN ESCHERICHIA-COLI
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DOI：
10.1111/j.1432-1033.1990.tb15314.x
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发表时间：
1990-01-26
期刊：
影响因子：
--
通讯作者：
NYGAARD, P
中科院分区：
文献类型：
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作者：
MENG, LM;KILSTRUP, M;NYGAARD, P
purR 基因编码一个抑制子 (PurR)，控制嘌呤生物合成酶的合成。通过SDS/聚丙烯酰胺凝胶电泳鉴定PurR的亚基为38-kDa的多肽。 purR-lacZ 转录融合的分析表明 purR 表达是自动调节的。凝胶阻滞和 DNase I 足迹实验证实了这一点，其中在 purR 的转录部分中鉴定出了两个 PurR 结合位点。研究发现，在野生型和 pur-lac 融合菌株中引入 purR 突变可以消除对嘌呤生物合成途径中除 purA 之外的所有基因的嘌呤抑制。
The purR gene encodes a repressor (PurR) controlling the synthesis of the enzymes of purine biosynthesis. The subunit of PurR was identified as a 38-kDa polypeptide by SDS/polyacrylamide gel electrophoresis. Analysis of a purR-lacZ transcriptional fusion indicated that purR expression is autoregulated. This was confirmed by gel retardation and DNase I footprinting experiments, where two PurR-binding sites were identified in the transcribed part of purR. Introduction of a purR mutation in wild-type and pur-lac fusion strains was found to abolish purine repression of all genes of the purine biosynthetic pathway except for purA.