Saliva-activated transmission (SAT) of Borrelia burgdorferi sensu stricto was demonstrated using real-time PCR and salivary gland extract (SGE) from partially fed Ixodes ricinus ticks. C3H/HeN mice were injected intradermally with 1.5 × 103 spirochetes mixed with 40 µg of SGE per mouse. The control group was inoculated with the same dose of spirochetes without SGE. The accelerating effect of SGE on spirochete proliferation was demonstrated on day 1 post infection, when a 4.2-fold increase in spirochetes was found in the skin and a 10-fold increase in the blood, compared with control mice. The data represent the first direct evidence of a SAT effect of I. ricinus SGE on infection with the Lyme disease agent B. burgdorferi.
Fotosyntetické organely eukaryot vznikly endosymbiózou, procesem, při kterém došlo k pohlcení fotosyntetické bakterie nebo eukaryotické řasy nefotosyntetickým eukaryotem. Tento jev měl za následek široké rozšíření fototrofie mezi eukaryoty z různých říší (Archaeplastida, Chromalveolata, Rhizaria, Excavata). Řada těchto organismů pak fotosyntézu v průběhu evoluce zase ztratila. Kromě zisku fotoautotrofie má endosymbióza zásadní důsledky pro mozaikovou skladbu genomu eukaryot a též pro získání nových vlastností a schopností. and Photosynthetic organelles in the eukaryotic cells were developed through endosymbiosis – the process during which a photosynthetic bacterium or an eukaryotic alga was swallowed by a non-photosynthetic eukaryote. As a result of this phenomenon, phototropism spread among eukaryotes of different kingdoms. However, many of these organisms lost photosynthesis during later evolution. Apart from gaining photoautotrophy, endosymbiosis has serious consequences for the mosaic composition of the eukaryotic genome and for its acquisition of new characteristics and abilities.
Marssoniella elegans Lemmermann, 1900, a parasite of ovarial tissues of the copepod Cyclops vicinus Uljanin, 1875, was studied as a representative of aquatic-clade microsporidia which form ''heteroinfectious spores'' (spores not infective to the original host as opposed to ''homoinfectious spores'' which are infective for the original host) and which thus should require an alternate host. Several structural characters of this microsporidian are similar to those of copepod morphs of microsporidia infecting mosquitoes. However, small subunit ribosomal DNA phylogeny indicates that caddis flies (Insecta, Trichoptera) might be the alternate hosts of Marssoniella. Ultrastructural data obtained are used to redefine the genus Marssoniella Lemmermann, 1900 and its type species Marssoniella elegans.