Dupont Chloé, Michon Anne-Laure, Jumas-Bilak Estelle, Nørskov-Lauritsen Niels, Chiron Raphaël, Marchandin Hélène
Université Montpellier 1, UMR5119 ECOSYM, Equipe Pathogènes et Environnements, U.F.R des Sciences Pharmaceutiques et Biologiques, 15 avenue Charles Flahault, 34093 Montpellier Cedex 5, France.
Université Montpellier 1, UMR5119 ECOSYM, Equipe Pathogènes et Environnements, U.F.R des Sciences Pharmaceutiques et Biologiques, 15 avenue Charles Flahault, 34093 Montpellier Cedex 5, France; Centre Hospitalier Régional Universitaire de Montpellier, Hôpital Arnaud de Villeneuve, Laboratoire de Bactériologie, 371 avenue du Doyen Gaston Giraud, 34295 Montpellier Cedex 5, France.
Infect Genet Evol. 2015 Jun;32:214-23. doi: 10.1016/j.meegid.2015.03.012. Epub 2015 Mar 16.
Achromobacter spp. are increasingly identified in Cystic Fibrosis (CF) patients and their ability to persistently colonize the CF respiratory tract (CFRT) suggests that Achromobacter species possess adaptive characteristics. We studied genome dynamics in 118 isolates recovered from 13 patients with Achromobacter chronic colonization (5-26 isolates per patient recovered over 13-61 months). Isolates were identified to species level by nrdA gene sequencing, subjected to Pulsed-Field Gel Electrophoresis (PFGE) and multiplex rep-PCR (MR-PCR), and rrs intragenomic diversity was studied by PCR-Temporal Temperature Gel Electrophoresis (TTGE). Intrapatient diversity was assessed: (i) from dynamics of XbaI and/or SpeI-based pulsotypes, (ii) from comparison of MR-PCR profiles, and (iii) by longitudinal analysis of rrs intragenomic diversity. Patients were chronically colonized by Achromobacter xylosoxidans (n=10), Achromobacter dolens (n=1) or Achromobacter insuavis (n=2). All strains displayed genomic diversification over time but A. insuavis showed higher pulsotype diversity compared to other species. Intragenomic rrs heterogeneity was found in strains from 6 of 13 patients and may be persistently observed. Achromobacter genome evolution observed during chronic colonization of the CFRT warrants further investigation of the adaptation features of the different species, as well as of the selective forces driving this adaptation in the CFRT.
无色杆菌属在囊性纤维化（CF）患者中越来越多地被发现，其在CF呼吸道（CFRT）中持续定植的能力表明无色杆菌属具有适应性特征。我们研究了从13例无色杆菌慢性定植患者中分离出的118株菌株的基因组动态（每位患者在13 - 61个月内分离出5 - 26株菌株）。通过nrdA基因测序将菌株鉴定到种水平，进行脉冲场凝胶电泳（PFGE）和多重重复聚合酶链反应（MR-PCR），并通过聚合酶链反应 - 时间温度凝胶电泳（TTGE）研究rrs基因内多样性。评估患者体内的多样性：（i）基于XbaI和/或SpeI脉冲型的动态变化，（ii）通过比较MR-PCR图谱，以及（iii）通过对rrs基因内多样性的纵向分析。患者被木糖氧化无色杆菌（n = 10）、迟钝无色杆菌（n = 1）或非嗜糖无色杆菌（n = 2）慢性定植。所有菌株随着时间推移都表现出基因组多样化，但与其他物种相比，非嗜糖无色杆菌显示出更高的脉冲型多样性。在13例患者中的6例患者的菌株中发现了基因内rrs异质性，并且可能持续观察到。在CFRT慢性定植期间观察到的无色杆菌基因组进化值得进一步研究不同物种的适应特征，以及驱动CFRT中这种适应的选择力。
