Genomic Analysis of a Pathogenicity Island in Uropathogenic Escherichia coli CFT073: Distribution of Homologous Sequences among Isolates from Patients with Pyelonephritis, Cystitis, and CatheterAssociated Bacteriuria and from Fecal Samples
Genomic Analysis of a Pathogenicity Island in Uropathogenic Escherichia coli CFT073: Distribution of Homologous Sequences among Isolates from Patients with Pyelonephritis, Cystitis, and CatheterAssociated Bacteriuria and from Fecal Samples
复制标题
DOI：
10.1128/iai.66.9.4411-4417.1998
复制
发表时间：
1998-09
影响因子：
3.1
通讯作者：
Debra M. Guyer;J. Kao;H. Mobley
中科院分区：
文献类型：
--
作者：
Debra M. Guyer;J. Kao;H. Mobley
摘要尿路感染是最常见的肾脏和泌尿系统疾病，大肠杆菌是最常见的病原体。尿路致病性菌株已被证明含有称为致病岛（PAI）的DNA块，这有助于它们的毒力。我们已经在一个高度同源的E染色体中确定了这些DNA区域之一。大肠杆菌菌株，CFT 073，分离自患有急性肾盂肾炎的女性的血液和尿液。57，988-bp的DNA片段具有定义PAI的特征，包括大于30 kb的大小，插入序列的存在，K-12和J 96起源的明显分段，GC含量（42.9%）不同于总基因组DNA（50.8%），以及毒力基因（hly和pap）的存在。在这一区域内，我们鉴定了44个开放阅读框，其中10个与K-12全基因组序列同源，4个与E. coli J 96编码HlyA溶血素，11个编码P菌毛，19个与J 96或K-12没有同源性。为了确定在CFT 073的派连接处发现的序列是否与其他尿路致病性E.大肠杆菌中，沿着派的长度分离沿着11个探针，并与从临床分离株（67个来自急性肾盂肾炎患者，38个来自膀胱炎患者，49个来自导管相关菌尿患者，27个来自粪便样品）分离的基因组DNA的斑点杂交。这些序列在与急性肾盂肾炎（79%）和膀胱炎（82%）临床综合征相关的菌株中比在与导管相关菌尿（58%）和粪便菌株（22%）中更常见（P < 0.001）。从这些区域，我们已经确定了一个假定的铁转运系统和基因以外的hly和pap，可能有助于致病性尿路E。大肠杆菌菌株。
ABSTRACT Urinary tract infection is the most frequently diagnosed kidney and urologic disease and Escherichia coli is by far the most common etiologic agent. Uropathogenic strains have been shown to contain blocks of DNA termed pathogenicity islands (PAIs) which contribute to their virulence. We have defined one of these regions of DNA within the chromosome of a highly virulentE. coli strain, CFT073, isolated from the blood and urine of a woman with acute pyelonephritis. The 57,988-bp stretch of DNA has characteristics which define PAIs, including a size greater than 30 kb, the presence of insertion sequences, distinct segmentation of K-12 and J96 origin, GC content (42.9%) different from that of total genomic DNA (50.8%), and the presence of virulence genes (hly and pap). Within this region, we have identified 44 open reading frames; of these 44, 10 are homologous to entries in the complete K-12 genome sequence, 4 are nearly identical to the sequences of E. coli J96 encoding the HlyA hemolysin, 11 encode P fimbriae, and 19 show no homology to J96 or K-12 entries. To determine whether sequences found within the junctions of the PAI of CFT073 were common to other uropathogenic strains ofE. coli, 11 probes were isolated along the length of the PAI and were hybridized to dot blots of genomic DNA isolated from clinical isolates (67 from patients with acute pyelonephritis, 38 from patients with cystitis, 49 from patients with catheter-associated bacteriuria, and 27 from fecal samples). These sequences were found significantly more often in strains associated with the clinical syndromes of acute pyelonephritis (79%) and cystitis (82%) than in those associated with catheter-associated bacteriuria (58%) and in fecal strains (22%) (P < 0.001). From these regions, we have identified a putative iron transport system and genes other than hly and pap that may contribute to the virulent phenotype of uropathogenic E. coli strains.