PROTEIN-DEGRADATION IN ESCHERICHIA-COLI - THE LON GENE CONTROLS THE STABILITY OF SULA PROTEIN
PROTEIN-DEGRADATION IN ESCHERICHIA-COLI - THE LON GENE CONTROLS THE STABILITY OF SULA PROTEIN
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DOI：
10.1073/pnas.80.2.358
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发表时间：
1983-01-01
期刊：
影响因子：
--
通讯作者：
GOTTESMAN, S
中科院分区：
文献类型：
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作者：
MIZUSAWA, S;GOTTESMAN, S
大肠杆菌lon突变体在异常蛋白的ATP依赖性蛋白水解中有缺陷。突变体也对紫外线（UV）敏感，因为暴露于UV后分隔被抑制。苏拉突变，分离作为抑制剂的紫外线敏感性与离子，不影响蛋白水解，但允许分隔后发生DNA损伤。我们已经证实了这一假设，苏拉基因的产品是由离子蛋白水解降解。如果苏拉（苏拉的产物）是一种紫外线诱导的分裂抑制剂，正如各种实验所表明的那样，lon（lon的产物）可能通过调节苏拉的半衰期来调节细胞分裂。我们从携带大肠杆菌ompA区的质粒中克隆了苏拉基因到λ噬菌体载体中。杆菌一种18千道尔顿的多肽被鉴定为苏拉基因的产物。脉冲追踪标记表明，在lon+细胞中苏拉蛋白的半衰期为1.2分钟，在lon-细胞中为19分钟。这项工作表明，lon蛋白水解影响天然E。coli蛋白。
Escherichia coli lon mutants are defective in the ATP-dependent proteolysis of abnormal proteins. The mutants are also sensitive to ultraviolet light (UV) in that septation is inhibited after exposure to UV. sulA mutations, isolated as suppressors of UV sensitivity unlinked to lon, do not affect proteolysis but allow septation to occur after DNA damage. We have confirmed the hypothesis that the product of the sulA gene is degraded by lon proteolysis. If sulA (the product of sulA) is a UV-inducible division inhibitor, as suggested by a variety of experiments, lon (the product of lon) may regulate cell division by regulating the half-life of sulA. We cloned the sulA gene in a bacteriophage lambda vector from a plasmid carrying the ompA region of E. coli. An 18-kilodalton polypeptide was identified as the product of the sulA gene. Pulse-chase labeling demonstrated that the half-life of the sulA protein is 1.2 min in lon+ cells and 19 min in lon- cells. This work demonstrates that lon proteolysis affects the stability of a native E. coli protein.