Bartonella henselae

Bartonella henselae ( dark particles ) in the heart valve of a human

Bartonella henselae is a gram-negative rod-shaped bacterium and the causative agent of cat scratch disease.

Properties

Bartonella spp. are gram-negative, aerobic, facultative intracellular bacteria. The bacterial genus is named after its discoverer Alberto Barton. They belong to the class of alpha proteobacteria and are phylogenetically closely related to Brucella spp., Agrobacterium spp. and Rhizobium spp. related. The species Bartonella henselae is known only since 1991. While we initially assumed that only cats come as a carrier of the pathogen in question, we now know that the disease can be detected in a variety of mammals. Ticks as vectors of B. henselae also discussed.

Next Agrobacterium tumefaciens B. henselae the only bacterium, which is shown to be able to inject DNA via a transport system in eukaryotic cells. In a study of human epithelial cells, a plasmid was transferred via the type IV secretion system and expressed in the cell line from the bacterium. In addition to demonstrating that this horizontal gene transfer between prokaryotes and eukaryotes is not an isolated case, the use of this system allows other methods for performing gene therapy.

Pathogenicity

Children fall ill after infection usually at the cat scratch disease ( KKK ). This transmitted by young cats or cat fleas to humans disease occurs at the beginning typically a papule at the inoculation site on which follows a mostly self-limiting lymphadenitis of the regional lymph nodes.

Among all human pathogenic bacteria Bartonella only have the ability to cause Vaskuloproliferationen. Especially immunocompromised patients (eg AIDS patients ) may to " bacillary angiomatosis " (BA; concerned here primarily the skin) or " peliosis hepatis " (PH) ill with infection of the liver. In 1983, for the first time reports a case of these " atypical subcutaneous AIDS-related infection ". 1991 Bartonella henselae has been identified as a triggering agent of " bacillary angiomatosis " about the pioneering molecular detection of 16S rDNA of the pathogen by David Relman and cultured in the consequence also of vasculoproliferative skin, bone or liver lesions of patients. Today, both Bartonella henselae and Bartonella quintana considered the catalyst for BA or PH.