Heterogeneous nuclear RNPs as targets of autoantibodies in systemic rheumatic diseases.

Objective: To investigate the abundance of autoantibodies to heterogeneous nuclear RNPs (hnRNPs) in systemic rheumatic diseases.

Methods: Recombinant human hnRNPs A1, B1, C1, E1, F, Gi, H1, I, K, and P2 were prepared. Antibodies to these antigens were determined by Western blotting and by enzyme-linked immunosorbent assay (ELISA) (for hnRNPs B1, E1, F, and H1) in serum samples obtained from patients with chronic fatigue syndrome (control subjects) and from patients with various connective tissue diseases.

Clinical and serological evaluation of a novel CENP-A peptide based ELISA.

Introduction: Anti-centromere antibodies (ACA) are useful biomarkers in the diagnosis of systemic sclerosis (SSc). ACA are found in 20 to 40% of SSc patients and, albeit with lower prevalence, in patients with other systemic autoimmune rheumatic diseases. Historically, ACA were detected by indirect immunofluorescence (IIF) on HEp-2 cells and confirmed by immunoassays using recombinant CENP-B.

Characterization of the posttranscriptional modifications in Legionella pneumophila small-subunit ribosomal RNA.

It is generally accepted that posttranscriptional modifications in RNA play a role in the fine-tuning of RNA function and the maintenance of RNA structure. This article describes the characterization of the posttranscriptional modifications in Legionella pneumophila 16S rRNA by mass spectrometry and reverse transcriptase assays. Eight modified nucleotides were identified and mapped in the 16S rRNA sequence.

Evidence for the presence of Legionella bacteriophages in environmental water samples.

The existence and preliminary characterization of bacteriophages active against the Gram-negative human pathogen Legionella pneumophila, the causative agent of a very severe form of pneumonia, are reported. Four phages belonging to the family of the Myoviridae were isolated from various fresh water environments, and preliminary characterization showed that these crude preparations infect exclusively bacteria belonging to the genus Legionella. Standard phage amplification, purification, and characterization procedures were, however, not efficiently applicable making more research into these novel phages and their mechanism of infection necessary.

The twin-arginine translocation pathway is necessary for correct membrane insertion of the Rieske Fe/S protein in Legionella pneumophila.

The twin-arginine translocation (Tat) pathway translocates folded proteins across the cytoplasmic membrane. Proteins transported through this secretion system typically carry two arginine residues in their signal peptide that is cleaved off during translocation. Recently, we demonstrated the presence of the Tat pathway in Legionella pneumophila Philadelphia-1 and the Rieske Fe/S protein PetA was one of the predicted Tat substrates.

The type II signal peptidase of Legionella pneumophila.

Legionella pneumophila is a facultative intracellular Gram-negative bacterium that has become an important cause of community-acquired and nosocomial pneumonia. Recent studies concerning the unravelling of bacterial virulence have suggested the involvement of protein secretion systems in bacterial pathogenicity. In this respect, the type II signal peptidase (LspA), which is specifically required for the maturation of lipoproteins, is of particular interest.

Legionella pneumophila Philadelphia-1 tatB and tatC affect intracellular replication and biofilm formation.

Legionella pneumophila is a facultative intracellular human pathogen and an important cause of Legionnaires' disease, a severe form of pneumonia. Recently, we showed the presence of a putative twin-arginine translocation (Tat) pathway in L. pneumophila Philadelphia-1.

First proteomic analysis of Legionella pneumophila based on its developing genome sequence.

The first proteomic analysis of the respiratory pathogen Legionella pneumophila ATCC 33152 is presented in this report. Two-dimensional gel electrophoresis of total cell extracts was carried out. In total, 130 protein spots were identified by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MS) or by quadruple time-of-flight tandem MS, including proteins correlated with virulence.

A putative twin-arginine translocation pathway in Legionella pneumophila.

Legionella pneumophila is a facultative intracellular human pathogen causing Legionnaires' disease, a severe form of pneumonia. Because of the importance of secretion pathways in virulence, we were interested in the possible presence of the twin-arginine translocation (Tat) pathway in L. pneumophila.

Novel transcriptional regulators of Legionella pneumophila that affect replication in Acanthamoeba castellanii.

Legionella pneumophila is commonly found in freshwater environments and is able to invade and replicate within amoebae and ciliated protozoa. Moreover, this bacterium is also able to replicate within human alveolar macrophages causing a severe form of pneumonia, designated Legionnaires' disease. L.