Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada.
J Infect Dis. 2011 Feb 1;203(3):383-92. doi: 10.1093/infdis/jiq054. Epub 2010 Dec 14.
Quorum sensing (QS) contributes to the virulence of Pseudomonas aeruginosa and Burkholderia cepacia complex lung infections. P. aeruginosa QS mutants are frequently isolated from patients with cystic fibrosis. The objective of this study was to determine whether similar adaptations occur over time in B. cepacia complex isolates. Forty-five Burkholderia multivorans and Burkholderia cenocepacia sequential isolates from patients with cystic fibrosis were analyzed for N-acyl-homoserine lactone activity. All but one isolate produced N-acyl-homoserine lactones. The B. cenocepacia N-acyl-homoserine lactone-negative isolate contained mutations in cepR and cciR. Growth competition assays were performed that compared B. cenocepacia clinical and laboratory defined wild-type and QS mutants. Survival of the laboratory wild-type and QS mutants varied, dependent on the mutation. The clinical wild-type isolate demonstrated a growth advantage over its QS mutant. These data suggest that there is a selective advantage for strains with QS systems and that QS mutations do not occur at a high frequency in B. cepacia complex isolates.
群体感应（QS）有助于铜绿假单胞菌和伯克霍尔德氏菌复合肺感染的毒力。铜绿假单胞菌 QS 突变体经常从囊性纤维化患者中分离出来。本研究的目的是确定伯克霍尔德氏菌复合菌株是否随着时间的推移发生类似的适应性变化。对来自囊性纤维化患者的 45 株鲍曼不动杆菌和洋葱伯克霍尔德菌连续分离株进行了 N-酰基高丝氨酸内酯活性分析。除了一个分离株外，所有分离株都产生了 N-酰基高丝氨酸内酯。N-酰基高丝氨酸内酯阴性的 B. cenocepacia 分离株包含 cepR 和 cciR 的突变。进行了生长竞争测定，比较了 B. cenocepacia 临床和实验室定义的野生型和 QS 突变体。实验室野生型和 QS 突变体的存活情况因突变而异。临床野生型分离株相对于其 QS 突变体表现出生长优势。这些数据表明，具有 QS 系统的菌株具有选择性优势，并且 QS 突变在伯克霍尔德氏菌复合菌株中并不高频发生。
