BACKGROUND There are no licensed vaccines available against Moraxella catarrhalis, a significant human respiratory pathogen. Lipooligosaccharide (LOS) based conjugate vaccines derived from individual serotype M. catarrhalis only showed partial protection coverage. A vaccine combining LOS conjugates of two or three serotypes might provide a broader protection. METHODS Mice were immunized intra...

Pathogenic members of the family Neisseriaceae produce specific receptors to acquire iron from their host's lactoferrin and transferrin. Recently, putative Moraxella catarrhalis lactoferrin receptor genes and a third open reading frame (lbpB, lbpA, and orf3) were cloned and sequenced. We describe the preliminary characterization of isogenic mutants deficient in LbpB, LbpA, or Orf3 protein.

conclusions it can be concluded that a. otitidis was the major causative agent of mee in children with ome. therefore clinicians should be aware that bacterial infection plays an important role in the progression of acute otitis media to ome in children of our region. results the bacterial cultures in 8.6% of samples were positive by conventional culture, with a. otitidis, m. catarrhalis and s....

Alterations of the airway microbiome are often associated with pulmonary diseases. For example, detection of the bacterial pathogen Moraxella catarrhalis in the upper airways is linked with an increased risk to develop or exacerbate asthma. However, the mechanisms by which M. catarrhalis augments allergic airway inflammation (AAI) remain unclear. We here characterized the cellular and soluble m...

A number of microorganisms are capable of binding immunoglobulins (Igs) in a manner, which excludes binding to conventional antigen binding sites. Interaction of such bacterial proteins with surface immunoglobulins leads to polyclonal activation of B-lymphocytes. A recent example is Moraxella catarrhalis that binds to B lymphocytes in an IgD-dependent manner and induces proliferation and differ...

Colonization of SARS-CoV-2 with specific bacteria may either protect or increase the risk disease severity. This study aimed to identify microbial organisms in lower respiratory tract and their association infection. was a cross-sectional conducted between May 2020 August 2021 at Tamale Public Health Laboratory Northern part Ghana. RT-PCRs for bacteriological cultures were performed on sputum s...

The Hfq protein is recognized as a global regulatory molecule that facilitates certain RNA-RNA interactions in bacteria. BLAST analysis identified a 630-nucleotide open reading frame in the genome of Moraxella catarrhalis ATCC 43617 that was highly conserved among M. catarrhalis strains and which encoded a predicted protein with significant homology to the Hfq protein of Escherichia coli. This ...

Growth of exponential-phase liquid cultures of Moraxella osloensis was inhibited by 0.5 U of penicillin G per ml. For this organism, low concentrations of penicillin acted primarily in a bacteriostatic rather than in a bactericidal manner. At higher concentrations of penicillin some killing did take place, but the rate of killing was rather slow and appeared to be independent of penicillin conc...