Evans D J, Pier G B, Coyne M J, Goldberg J B
Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115-5899.
Mol Microbiol. 1994 Aug;13(3):427-34. doi: 10.1111/j.1365-2958.1994.tb00437.x.
Strains of Pseudomonas aeruginosa initially isolated from patients with cystic fibrosis (CF) often express a smooth lipopolysaccharide (LPS) containing many long O side-chain antigens, but once a chronic infection is established, strains recovered from these patients express little or no LPS O antigen. The genetic basis for this loss of O antigen expression by P. aeruginosa CF isolates is unknown. We report here that 20 CF isolates of P. aeruginosa, 13 of which are LPS-rough, were each capable of expressing serogroup O11 antigen when provided with the rfb locus from P. aeruginosa serogroup O11 strain PA103 on the recombinant plasmid pLPS2. Eight of the thirteen LPS-rough isolates co-expressed another, presumably endogenous, O antigen when they contained pLPS2. Different subcloned regions of pLPS2 complemented distinct strains to restore endogenous O antigen expression. These data suggest that the loss of O antigen expression by P. aeruginosa CF isolates results from alterations specific to the rfb region, and is not due to mutations involving other loci or ancillary LPS genes.
最初从囊性纤维化（CF）患者中分离出的铜绿假单胞菌菌株通常表达含有许多长O侧链抗原的光滑脂多糖（LPS），但一旦建立慢性感染，从这些患者中分离出的菌株表达很少或不表达LPS O抗原。铜绿假单胞菌CF分离株O抗原表达丧失的遗传基础尚不清楚。我们在此报告，20株铜绿假单胞菌CF分离株（其中13株为LPS粗糙型），当在重组质粒pLPS2上提供来自铜绿假单胞菌O11血清型菌株PA103的rfb基因座时，每株都能够表达O11血清群抗原。13株LPS粗糙型分离株中的8株在含有pLPS2时共表达另一种可能是内源性的O抗原。pLPS2的不同亚克隆区域补充了不同的菌株以恢复内源性O抗原表达。这些数据表明，铜绿假单胞菌CF分离株O抗原表达的丧失是由rfb区域特有的改变引起的，而不是由于涉及其他基因座或辅助LPS基因的突变。
