Mederos L, Valdivia J A, Valero-Guillén P L
Laboratorio Nacional de Referencia e Investigaciones de Tuberculosis y Micobacterias, Centro Colaborador OPS/OMS, Instituto de Medicina Tropical Pedro Kourí (IPK), La Habana, Cuba.
J Appl Microbiol. 2008 Aug;105(2):602-14. doi: 10.1111/j.1365-2672.2008.03796.x. Epub 2008 Apr 4.
To determine the composition of polar glycopeptidolipids (pGPLs) of Mycobacterium simiae and, particularly, those of 'habana' strains, in a search for specific markers given the immunogenic potential of 'habana' TMC 5135 in experimental tuberculosis.
pGPLs were determined in free lipid extracts using electrospray ionization-ion trap-mass spectrometry (ESI-IT-MS), working in both negative- and positive-ion mode. In the case of TMC 5135, the presence of the previously characterized GPL-II (containing 2,4-di-O-CH(3) glucuronic acid as distal sugar in the oligosaccharide antigenic moiety) and GPL-III (containing 4-O-CH(3) glucuronic acid as distal sugar) was confirmed using MS/MS and MS/MS/MS approaches. Interestingly, some 'habana' strains presented variants of GPL-II, designated GPL-II'-A and GPL-II'-B. A di-O-CH(3)-deoxy-hexose (tentatively, 2,3-di-O-CH(3)-fucose) was identified as the penultimate sugar in the oligosaccharide moiety of GPL-II'-A, whereas in GPL-II'-B the penultimate sugar was fucose (tentative identification). On the contrary, the distal sugar of the oligosaccharide chain of pGPLs of Myco. simiae ATCC 25275(T) was identified as tri-O-CH(3)-glucuronic acid (designated GPL-sim(T)-I, with two variants: GPL-sim(T)-I-A and GPL-sim(T)-I-B), O-CH(3)-glucuronic acid (designated GPL-sim(T)-II) and di-O-CH(3)-glucuronic acid (GPL-II'-A and GPL-II'-B). The penultimate sugar of the oligosaccharide chain of GPL-sim(T)-I-A and GPL-sim(T)-II was identified as di-O-CH(3)-deoxy-hexose (tentatively, 2,3-di-O-CH(3) fucose), and that of GPL-sim(T)-I-B as deoxy-hexose (tentatively, fucose). In all strains studied, each M-H and M+Na ion was revealed as a mixture of homologous compounds varying in the number of -O-CH(3) groups present in the oligosaccharide moiety and in the length of the fatty acyl linked to the peptide.
The present work indicates that, within a similar general pattern of pGPLs, different strains of Myco. simiae present some variations, so that new compounds (GPL-II'-A, GPL-II'-B, GPL-sim(T)-I-A, GPL-sim(T)-I-B and GPL-sim(T)-II) were defined. Noteworthy was the fact that the 'habana' strains clearly differed from the type strain of Myco. simiae.
The data obtained can be used in the delineation of the 'habana' group of Myco. simiae, including the quality control of the immunogenic strain 'habana' TMC 5135.
鉴于“哈瓦那”菌株TMC 5135在实验性结核病中的免疫原性潜力，确定猿分枝杆菌的极性糖肽脂（pGPLs）的组成，特别是“哈瓦那”菌株的pGPLs组成，以寻找特异性标志物。
使用电喷雾电离-离子阱-质谱（ESI-IT-MS）在正负离子模式下测定游离脂质提取物中的pGPLs。对于TMC 5135，采用MS/MS和MS/MS/MS方法确认了先前鉴定的GPL-II（在寡糖抗原部分中含有2,4-二-O-CH(3)葡萄糖醛酸作为末端糖）和GPL-III（含有4-O-CH(3)葡萄糖醛酸作为末端糖）的存在。有趣的是，一些“哈瓦那”菌株呈现出GPL-II的变体，命名为GPL-II'-A和GPL-II'-B。一种二-O-CH(3)-脱氧己糖（初步鉴定为2,3-二-O-CH(3)-岩藻糖）被鉴定为GPL-II'-A寡糖部分的倒数第二个糖，而在GPL-II'-B中倒数第二个糖为岩藻糖（初步鉴定）。相反，猿分枝杆菌ATCC 25275(T)的pGPLs寡糖链的末端糖被鉴定为三-O-CH(3)-葡萄糖醛酸（命名为GPL-sim(T)-I，有两个变体：GPL-sim(T)-I-A和GPL-sim(T)-I-B）、O-CH(3)-葡萄糖醛酸（命名为GPL-sim(T)-II）和二-O-CH(3)-葡萄糖醛酸（GPL-II'-A和GPL-II'-B）。GPL-sim(T)-I-A和GPL-sim(T)-II寡糖链的倒数第二个糖被鉴定为二-O-CH(3)-脱氧己糖（初步鉴定为2,3-二-O-CH(3)岩藻糖），而GPL-sim(T)-I-B的倒数第二个糖为脱氧己糖（初步鉴定为岩藻糖）。在所有研究的菌株中，每个M-H和M+Na离子都显示为同源化合物的混合物，这些同源化合物在寡糖部分中存在的-O-CH(3)基团数量以及与肽相连的脂肪酰基长度上有所不同。
目前的研究表明，在pGPLs的相似总体模式内，猿分枝杆菌的不同菌株存在一些差异，因此定义了新的化合物（GPL-II'-A、GPL-II'-B、GPL-sim(T)-I-A、GPL-sim(T)-I-B和GPL-sim(T)-II）。值得注意的是，“哈瓦那”菌株与猿分枝杆菌的模式菌株明显不同。
所获得的数据可用于猿分枝杆菌“哈瓦那”组的划分，包括免疫原性菌株“哈瓦那”TMC 5135的质量控制。
