Matteo Mario J, Armitano Rita I, Romeo Mariela, Wonaga Andres, Olmos Martín, Catalano Mariana
Int J Mol Epidemiol Genet. 2011 Aug 30;2(3):286-91. Epub 2011 Jul 23.
Helicobacter pylori BabA adhesin metastability could yield variants with potential for periodic activation and deactivation of their mediated adherence. babA/B or babB/A chimeras could play an important role in translational regulation. We investigated the frequency of different bab gene profiles in paired isolates from antrum and corpus recovered from patients with chronic gastritis. Isolates from 174 biopsies from 34 patients were included, and bab genes at the three common chromosomal loci were investigated. Inter-micro-niche variation was found in 1/4 patients, counting duplicate copies of babA or babB, babB/A or babA/B chimeras, opposite location of babA and babB or babC and babB, and absence of babB ATG translational codon. Truncated BabA was identified in 2/34 patients without inter-micro-niche variation. Isolates from 12/34 patients harbored babA/B or babB/A chimeras -either in one, several or all micro-niches indicating that chimera formation is a common mechanism to control BabA expression. To note, babA gene was absent in 11/34 patients, and in this population, babA/B chimeras which lack expression predominated over babB/A, able to exhibit Le(b) binding phenotype.
幽门螺杆菌BabA黏附素的亚稳定性可产生具有介导黏附周期性激活和失活潜力的变体。babA/B或babB/A嵌合体可能在翻译调控中发挥重要作用。我们调查了从慢性胃炎患者胃窦和胃体中分离出的配对菌株中不同bab基因谱的频率。纳入了34例患者174份活检样本的分离菌株，并研究了三个常见染色体位点的bab基因。在1/4的患者中发现了微生态位间的变异，包括babA或babB的重复拷贝、babB/A或babA/B嵌合体、babA和babB或babC和babB的相反位置，以及babB起始密码子ATG的缺失。在2/34例无微生态位间变异的患者中鉴定出截短的BabA。12/34例患者的分离菌株在一个、几个或所有微生态位中都含有babA/B或babB/A嵌合体，这表明嵌合体形成是控制BabA表达的常见机制。值得注意的是，11/34例患者中不存在babA基因，在这一群体中，缺乏表达的babA/B嵌合体比能够表现出Le(b)结合表型的babB/A嵌合体占优势。
