Sánchez David, Gomila Margarita, Bennasar Antonio, Lalucat Jorge, García-Valdés Elena
Microbiologia, Departament de Biologia, Edifici Guillem Colom, Universitat de les Illes Balears, Campus UIB, Palma de Mallorca, Spain.
Microbiologia, Departament de Biologia, Edifici Guillem Colom, Universitat de les Illes Balears, Campus UIB, Palma de Mallorca, Spain; Instituto Universitario de Investigación en Ciencias de la Salud (IUNICS-UIB) Universitat de les Illes Balears, Campus UIB, Palma de Mallorca, Spain.
PLoS One. 2014 Oct 15;9(10):e107754. doi: 10.1371/journal.pone.0107754. eCollection 2014.
The genomes of Pseudomonas aeruginosa isolates of the new sequence type ST-1146, three environmental (P37, P47 and P49) and one clinical (SD9) isolates, with differences in their antibiotic susceptibility profiles have been sequenced and analysed. The genomes were mapped against P. aeruginosa PAO1-UW and UCBPP-PA14. The allelic profiles showed that the highest number of differences were in "Related to phage, transposon or plasmid" and "Secreted factors" categories. The clinical isolate showed a number of exclusive alleles greater than that for the environmental isolates. The phage Pf1 region in isolate SD9 accumulated the highest number of nucleotide substitutions. The ORF analysis of the four genomes assembled de novo indicated that the number of isolate-specific genes was higher in isolate SD9 (132 genes) than in isolates P37 (24 genes), P47 (16 genes) and P49 (21 genes). CRISPR elements were found in all isolates and SD9 showed differences in the spacer region. Genes related to bacteriophages F116 and H66 were found only in isolate SD9. Genome comparisons indicated that the isolates of ST-1146 are close related, and most genes implicated in pathogenicity are highly conserved, suggesting a genetic potential for infectivity in the environmental isolates similar to the clinical one. Phage-related genes are responsible of the main differences among the genomes of ST-1146 isolates. The role of bacteriophages has to be considered in the adaptation processes of isolates to the host and in microevolution studies.
对新序列类型ST-1146的铜绿假单胞菌分离株（三株环境分离株P37、P47和P49以及一株临床分离株SD9）进行了测序和分析，这些分离株的抗生素敏感性谱存在差异。将这些基因组与铜绿假单胞菌PAO1-UW和UCBPP-PA14进行比对。等位基因谱显示，差异数量最多的是“与噬菌体、转座子或质粒相关”和“分泌因子”类别。临床分离株显示出比环境分离株更多的独特等位基因。分离株SD9中的噬菌体Pf1区域积累的核苷酸替换数量最多。对四个从头组装的基因组进行的开放阅读框分析表明，分离株SD9中分离株特异性基因的数量（132个基因）高于分离株P37（24个基因）、P47（16个基因）和P49（21个基因）。在所有分离株中均发现了CRISPR元件，且SD9在间隔区存在差异。仅在分离株SD9中发现了与噬菌体F116和H66相关的基因。基因组比较表明，ST-1146的分离株密切相关，且大多数与致病性相关的基因高度保守，这表明环境分离株与临床分离株具有相似的感染遗传潜力。噬菌体相关基因是ST-1146分离株基因组之间主要差异的原因。在分离株适应宿主的过程以及微观进化研究中，必须考虑噬菌体的作用。
