We determined that the putative upstream promoter of the long transcript (P1) of ompA, the gene encoding the major outer membrane protein of Chlamydia trachomatis L2, is recognized in vitro by the major sigma factor of chlamydiae, sigma 66. We found no evidence that the putative downstream promoter of the short ompA transcript (P1) is functional in vitro. RNase protection of guanylyltransferase...

The current topological model for the Escherichia coli outer membrane protein OmpA predicts eight N-terminal transmembrane segments followed by a long periplasmic tail. Several recent reports have raised serious doubts about the accuracy of this prediction. An alternative OmpA model has been constructed using (1) computer-aided predictions developed specifically to predict topology of bacterial...

granulocytic ehrlichiosis in Europe: clinical and laboratory findings for four patients from Slovenia. Use of CRH/he Lyme disease mouse model for the recovery of a Spanish isolate of Borrelia garinii from erythema migrans lesions. To the Editor: Five species of tick-associated rickettsiae have been identified in China; of these, three are human pathogens and two are of unknown pathogenicity (1)...

The bioemulsifier of Acinetobacter radioresistens KA53, referred to as alasan, is a high-molecular-weight complex of polysaccharide and protein. Recently, one of the alasan proteins, with an apparent molecular mass of 45 kDa, was purified and shown to constitute most of the emulsifying activity. The N-terminal sequence of the 45-kDa protein showed high homology to an OmpA-like protein from Acin...

Chlamydia trachomatis is an important human pathogen that undergoes a characteristic development cycle correlating with stage-specific gene expression profiles. Taking advantage of recent developments in the genetic transformation in C. trachomatis, we constructed a versatile green fluorescent protein (GFP) reporter system to study the development-dependent function of C. trachomatis promoters ...

ompA, and htrA); 11 of these ticks were from the patient’s dogs. In all properties where ticks were collected, at least 1 was PCR positive. Thus, we detected R. parkeri in half (4/8) of investigated households. All the sequences generated for the ompA and htrA genes showed 100% identity to sequences from the Rickettsia parkeri strain Portsmouth (GenBank accession no. CP003341.1). We deposited i...

We examined the way the major outer membrane protein OmpA of Salmonella enterica serovar Typhimurium is recognized by the mouse immune system, by raising a panel of 12 monoclonal antibodies (MAbs) against this protein. Interaction between OmpA and these MAbs is competitively inhibited with several-hundredfold dilutions of mouse polyclonal sera obtained by immunization with live or heat-killed w...

Since sensory system allows organisms to perceive and interact with their external environment, any disruption in functioning may have detrimental consequences on survival. Ocean acidification has been shown potentially impair olfactory fish it is therefore essential develop biological tools contributing better characterize such effects. The marker protein (omp) gene involved the maturation act...

Sequences of the major outer membrane protein (MOMP) gene (ompA) and the outer membrane complex B protein gene (omcB) from Chlamydia trachomatis, Chlamydia pneumoniae, and Chlamydia psittaci were analyzed for evidence of intragenic recombination and for linkage equilibrium. The Sawyer runs test, compatibility matrices, and index of association analyses provided substantial evidence that there h...

A Klebsiella pneumoniae ompA mutant was more susceptible to antimicrobial peptides (APs) than the wild type. Susceptibility did not result from surface changes other than the absence of OmpA. Our data suggest that OmpA is implicated in the activation of yet-unknown systems dedicated to ameliorating AP cytotoxicity.