African trypanosomes thrive in the bloodstream and tissue spaces of a wide range of mammalian hosts. Infections of cattle cause an enormous socio-economic burden in sub-Saharan Africa. A hallmark of the trypanosome lifestyle is the flagellate's incessant motion. This work details the cell motility behavior of the four livestock-parasites Trypanosoma vivax, T. brucei, T. evansi and T. congolense...

Hyperactivacion of sperm entails increases in the flagellar wave amplitude and the asymmetry of flagellar movement. In simple media on glass slides, hyperactivated sperm are not highly progressive. Nevertheless, we have evidence that hyperactivated sperm within the oviduct possess greater ability to reach the oocyte plasmalemma than normal activated sperm. First, hyperactivated rabbit sperm, fl...

Trypanosoma brucei is a unicellular flagellated eukaryotic parasite that causes African trypanosomiasis in human and domestic animals with devastating health and economic consequences. Recent studies have revealed the important roles of the single flagellum of T. brucei in many aspects, especially that the flagellar motility is required for the viability of the bloodstream form T. brucei, sugge...

UNLABELLED Many polarly flagellated bacteria require similar two-component regulatory systems (TCSs) and σ(54) to activate transcription of genes essential for flagellar motility. Herein, we discovered that in addition to the flagellar type III secretion system (T3SS), the Campylobacter jejuni flagellar MS ring and rotor are required to activate the FlgSR TCS. Mutants lacking the FliF MS ring a...

The rhythmic movement of the microtubular axostyle in the termite flagellate, Pyrsonympha vertens, was analyzed with polarization and electron microscopy. The protozoan axostyle is birefringent as a result of the semi-crystalline alignment of approximately 2,000 microtubules. The birefringence of the organelle permits analysis of the beat pattern in vivo. Modifications of the beat pattern were ...

The large antigenic diversity (over 2,300 serotypes) expressed by SalmoneUla strains can probably be observed at the genetic level. The phase 1 flagellin gene fliC was amplified, and the amplified fragment was cleaved with a mixture of both endonucleases TaqI and ScaI. The restriction patterns observed allowed differentiation of flagellar types b, i, d, j, l,v, and z1o. Flagellar group g (g,m, ...

When Chlamydomonas cells are deflagellated by pH shock or mechanical shear the nucleus rapidly moves toward the flagellar basal apparatus at the anterior end of the cell. During flagellar regeneration the nucleus returns to a more central position within the cell. The nucleus is connected to the flagellar apparatus by a system of fibers, the flagellar roots (rhizoplasts), which undergo a dramat...

In Trypanosoma brucei, glycosylphosphatidylinositol phospholipase C (GPI-PLC) is a virulence factor that releases variant surface glycoprotein (VSG) from dying cells. In live cells, GPI-PLC is localised to the plasma membrane where it is concentrated on the flagellar membrane, so activity or access must be tightly regulated as very little VSG is shed. Little is known about regulation except tha...

In the human intestinal pathogen Clostridium difficile, flagella promote adherence to intestinal epithelial cells. Flagellar gene expression also indirectly impacts production of the glucosylating toxins, which are essential to diarrheal disease development. Thus, factors that regulate the expression of the flgB operon will likely impact toxin production in addition to flagellar motility. Here,...

Chlamydomonas reinhardtii, a bi-flagellated green alga, is a model organism for studies of flagella or cilia related activities including cilia-based signaling, flagellar motility and flagellar biogenesis. Calcium has been shown to be a key regulator of these cellular processes whereas the signaling pathways linking calcium to these cellular functions are less understood. Calcium-dependent prot...