Molecular cloning, expression, and immunogenicity of MTB12, a novel low-molecular-weight antigen secreted by Mycobacterium tuberculosis.
Molecular cloning, expression, and immunogenicity of MTB12, a novel low-molecular-weight antigen secreted by Mycobacterium tuberculosis.
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结核分枝杆菌分泌的新型低分子量抗原 MTB12 的分子克隆、表达和免疫原性。
DOI：
10.1128/iai.66.9.4208-4214.1998
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发表时间：
1998
影响因子：
3.1
通讯作者：
Skeiky,YA
中科院分区：
文献类型：
--
作者：
Webb,JR;Vedvick,TS;Alderson,MR;Guderian,JA;Jen,SS;Ovendale,PJ;Johnson,SM;Reed,SG;Skeiky,YA
结核分枝杆菌分泌到培养基中的蛋白质被认为在保护性免疫反应的发展中发挥重要作用。在本报告中，我们描述了由分枝杆菌分泌的新型低分子量抗原（MTB12）的分子克隆。结核。 MTB12 基因的序列分析表明，该蛋白最初合成为包含 48 个氨基酸疏水前导序列的 16.6 kDa 前体蛋白。培养滤液中发现的成熟、完全加工形式的 MTB12 蛋白的分子量为 12.5 kDa。 MTB12蛋白是构成M的主要成分。结核菌培养上清液中的蛋白质，并且似乎至少与其他几种充分表征的培养物滤液蛋白质（包括 85B 复合物的成员）一样丰富。 MTB12 由单拷贝基因编码，该基因存在于 M 的强毒株和无毒株中。结核病复合体，M 的 BCG 菌株。牛，和M。麻风病。含有 N 端六组氨酸标签的重组 MTB12 在大肠杆菌中表达，并通过亲和层析纯化。重组MTB12蛋白在许多纯化蛋白衍生物阳性(PPD+)人类供体的外周血单核细胞中引发体外增殖反应，但对PPD-供体则不产生增殖反应。
Proteins secreted into the culture medium byMycobacterium tuberculosisare thought to play an important role in the development of protective immune responses. In this report, we describe the molecular cloning of a novel, low-molecular-weight antigen (MTB12) secreted byM. tuberculosis. Sequence analysis of the MTB12 gene indicates that the protein is initially synthesized as a 16.6-kDa precursor protein containing a 48-amino-acid hydrophobic leader sequence. The mature, fully processed form of MTB12 protein found in culture filtrates has a molecular mass of 12.5 kDa. MTB12 protein constitutes a major component of theM. tuberculosisculture supernatant and appears to be at least as abundant as several other well-characterized culture filtrate proteins, including members of the 85B complex. MTB12 is encoded by a single-copy gene which is present in both virulent and avirulent strains of theM. tuberculosiscomplex, the BCG strain ofM. bovis, andM. leprae. Recombinant MTB12 containing an N-terminal six-histidine tag was expressed inEscherichia coliand purified by affinity chromatography. Recombinant MTB12 protein elicited in vitro proliferative responses from the peripheral blood mononuclear cells of a number of purified protein derivative-positive (PPD+) human donors but not from PPD−donors.