Garbe T R, Hibler N S, Deretic V
Department of Microbiology and Immunology, University of Texas Health Science Center San Antonio 78284, USA.
Infect Immun. 1999 Jan;67(1):460-5. doi: 10.1128/IAI.67.1.460-465.1999.
In contrast to the apparent paucity of Mycobacterium tuberculosis response to reactive oxygen intermediates, this organism has evolved a specific response to nitric oxide challenge. Exposure of M. tuberculosis to NO donors induces the synthesis of a set of polypeptides that have been collectively termed Nox. In this work, the most prominent Nox polypeptide, Nox16, was identified by immunoblotting and by N-terminal sequencing as the alpha-crystallin-related, 16-kDa small heat shock protein, sHsp16. A panel of chemically diverse donors of nitric oxide, with the exception of nitroprusside, induced sHsp16 (Nox16). Nitroprusside, a coordination complex of Fe2+ with a nitrosonium (NO+) ion, induced a 19-kDa polypeptide (Nox19) homologous to the nonheme bacterial ferritins. We conclude that the NO response in M. tuberculosis is dominated by increased synthesis of the alpha-crystallin homolog sHsp16, previously implicated in stationary-phase processes and found in this study to be a major M. tuberculosis protein induced upon exposure to reactive nitrogen intermediates.
与结核分枝杆菌对活性氧中间体的明显反应匮乏形成对比的是，该生物体已进化出对一氧化氮挑战的特定反应。将结核分枝杆菌暴露于一氧化氮供体可诱导一组统称为Nox的多肽的合成。在这项工作中，通过免疫印迹和N端测序确定最突出的Nox多肽Nox16为α-晶状体蛋白相关的16 kDa小热休克蛋白sHsp16。除硝普钠外，一组化学性质不同的一氧化氮供体均可诱导sHsp16（Nox16）。硝普钠是Fe2+与亚硝酰离子（NO+）的配位络合物，可诱导一种与非血红素细菌铁蛋白同源的19 kDa多肽（Nox19）。我们得出结论，结核分枝杆菌中的一氧化氮反应主要由α-晶状体蛋白同源物sHsp16的合成增加所主导，sHsp16先前与稳定期过程有关，并且在本研究中发现它是结核分枝杆菌暴露于活性氮中间体时诱导产生的主要蛋白质。
