Acinetobacter baumannii has emerged as a nosocomial pathogen with an increased prevalence of multidrug-resistant strains. The role of the outer membrane protein A (OmpA) in antimicrobial resistance remains poorly understood. In this report, disruption of the ompA gene led to decreased MICs of chloramphenicol, aztreonam, and nalidixic acid. We have characterized, for the first time, the contribu...

Outer membrane protein A (OmpA) is a multifaceted predominant outer membrane protein of Escherichia coli and other Enterobacteriaceae whose role in the pathogenesis of various bacterial infections has recently been recognized. Here, the role of OmpA on the virulence of Shigella flexneri has been investigated. An ompA mutant of wild-type S. flexneri 5a strain M90T was constructed (strain HND92) ...

Objective(s): Acinetobacter baumannii is one the most dangerous opportunistic pathogens in hospitalized infections. This bacterium is resistant to 90% of commercial antibiotics. Therefore, developing new strategies to cure A. baumannii-infections is urgent. The DNA vaccines new approach in which the immunogen can be directly expressed inside the target cells through cl...

The signal sequence of the precursor of the Escherichia coli outer membrane protein OmpA was altered by oligonucleotide insertions into the corresponding gene. In one case, OmpA-S1, the hydrophobic core of the signal peptide, is reduced from 12 to 10 residues, and one positive charge is added near the NH2-terminus. In another case, OmpA-P1, the hydrophobic core is extended from 12 to 16 residue...

Adherence of enterohemorrhagic Escherichia coli (EHEC) to the intestinal epithelium is essential for initiation of infection. Intimin is the only factor demonstrated to play a role in intestinal colonization by EHEC O157:H7. Other attempts to identify additional adhesion factors in vitro have been unsuccessful, suggesting that expression of these factors is under tight regulation. We sought to ...

Acinetobacter species show high levels of intrinsic resistance to many antibiotics. The major protein species in the outer membrane of Acinetobacter baumannii does not belong to the high-permeability trimeric porin family, which includes Escherichia coli OmpF/OmpC, and instead is a close homolog of E. coli OmpA and Pseudomonas aeruginosa OprF. We characterized the pore-forming function of this ...

DNA sequences coding for 81% of the ompA gene from 24 chlamydial strains, representing all chlamydial species, were determined from DNA amplified by polymerase chain reactions. Chlamydial strains of serovars and strains with similar chromosomal restriction fragment length polymorphism had identical ompA DNA sequences. The ompA sequences were segregated into 23 different ompA alleles and aligned...

BACKGROUND Genital chlamydia infection is the most commonly diagnosed sexually transmitted infection in the UK. C. trachomatis genital infections are usually caused by strains which fall into two pathovars: lymphogranuloma venereum (LGV) and the genitourinary genotypes D-K. Although these genotypes can be discriminated by outer membrane protein gene (ompA) sequencing or multi-locus sequence typ...

BACKGROUND Chlamydia trachomatis is one of the most prevalent bacterial sexually transmitted infection in China. Although C. trachomatis genotypes can be discriminated by outer membrane protein gene (ompA) sequencing, currently available methods have limited resolutions. This study used a high-resolution genotyping method, namely, multilocus variable number tandem-repeat analysis with ompA sequ...

Type 1 pilus directs bladder epithelial binding and invasion by uropathogenic Escherichia coli (UPEC) in the initial stage of cystitis, but the bacterial determinants of postinvasion events in the pathogenesis of cystitis are largely undetermined. We show here that the UPEC outer membrane protein A (OmpA), a monomeric, major, integral protein component of the bacterial outer membrane, functions...