Reva Oleg, Bezuidt Oliver
Bioinformatics and Computational Biology Unit; Department of Biochemistry; University of Pretoria; Pretoria, South Africa.
Mob Genet Elements. 2012 Mar 1;2(2):96-100. doi: 10.4161/mge.19963.
Mankind is confronted by the outbreaks of highly virulent and multi-drug resistant pathogens. The outbreak strains often belong to well-known diseases associated species such as Salmonella, Klebsiella and Mycobacterium, but even normally commensal and environmental microorganisms may suddenly acquire properties of virulent bacteria and cause nosocomial infections. The acquired virulence is often associated with lateral exchange of pathogenicity genomic islands containing drug and heavy metal resistance determinants. Metal ions are used by the immune system of macro-organisms against bactericidal agents. The ability to control heavy metal homeostasis is a factor that allows the survival of pathogenic microorganisms in macrophages. In this paper, we investigate the origin of heavy metal resistance operons in the recent outbreak strains and the possible routes which may lead to acquisitions of these genes by potentially new pathogens. We hypothesize that new outbreak microorganisms appear intermittently on an intersection of the non-specialized, genetically naïve strains of potential pathogens and virulence factor comprising vectors (plasmid and/or phages) newly generated in the environmental microflora. Global contamination of the environment and climate change may also have an effect toward the acceleration and appearance of new pathogens.
人类面临着高毒力和多重耐药病原体的爆发。爆发菌株通常属于与沙门氏菌、克雷伯氏菌和分枝杆菌等知名疾病相关的物种，但即使是通常共生的和环境中的微生物也可能突然获得致病细菌的特性并引起医院感染。获得的毒力通常与含有药物和重金属抗性决定因素的致病性基因组岛的横向交换有关。金属离子被大型生物体的免疫系统用于对抗杀菌剂。控制重金属稳态的能力是致病微生物在巨噬细胞中存活的一个因素。在本文中，我们研究了近期爆发菌株中重金属抗性操纵子的起源以及潜在新病原体可能获得这些基因的途径。我们假设新的爆发微生物间歇性地出现在潜在病原体的非专业化、基因单纯的菌株与环境微生物群中新产生的包含毒力因子的载体（质粒和/或噬菌体）的交叉点上。全球环境污染和气候变化也可能对新病原体的加速出现产生影响。
