Lipid modification of the Cu,Zn superoxide dismutase from Mycobacterium tuberculosis
Lipid modification of the Cu,Zn superoxide dismutase from Mycobacterium tuberculosis
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DOI：
10.1042/0264-6021:3590017
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发表时间：
2001-10-01
影响因子：
4.1
通讯作者：
Battistoni, A
中科院分区：
文献类型：
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作者：
D'Orazio, M;Folcarelli, S;Battistoni, A
结核分枝杆菌铜锌超氧化物歧化酶（Cu,ZnSOD）的前导序列包含一个原核膜脂蛋白附着位点。在本研究中，我们发现当该蛋白在结核分枝杆菌或大肠杆菌中表达时，其具有可检测的SOD活性，被脂质修饰并与细菌膜相关联。这些结果首次证明了铜锌超氧化物歧化酶的脂质修饰。对现有数据库中存在的sodC基因的分析表明，脂质修饰的相同信号也存在于其他分枝杆菌和革兰氏阳性菌的sodC基因产物中，并且独特地存在于革兰氏阴性菌鼠伤寒沙门氏菌的两种不同的sodC基因产物中。还提供了证据表明结核分枝杆菌sodC在响应人类巨噬细胞吞噬作用时上调，这表明铜锌超氧化物歧化酶参与了促进分枝杆菌细胞内生长的机制。
The leader sequence of Mycobacterium tuberculosis Cu,Zn superoxide dismutase (Cu,ZnSOD) contains a prokaryotic membrane lipoprotein attachment site. In the present study. we have found that the protein, which exhibits detectable SOD activity, is lipid-modified and associated with the bacterial membrane when expressed either in Al. tuberculosis or in Escherichia coli. These results provide the first demonstration of lipid modification of a Cu,ZnSOD. An analysis of the sodC genes present in available databases indicates that the same signal for lipid modification is also present in the sodC gene products from other mycobacteria and Gram-positive bacteria and, uniquely, in two distinct sodC gene products from the Gram-negative bacterium Salmonella typhimurium. Evidence is also provided for an up-regulation of M. tuberculosis sodC in response to phagocytosis by human macrophages, suggesting that Cu,ZnSOD is involved in the mechanisms that facilitate mycobacterial intracellular growth.