Sensory Equipment of the Antennal Flagellum of Several Species of Damalinia (Phthiraptera: Trichodectidae)

Sensilla comprising the sensory equipment of the antennal flagellum of eight species of Damalinia were studied using light and scanning electron microscopy. The sensillar complex consists of three pore organs and two sensilla coeloconica in both males and females. No relationship between their relative position in different genera and species has been found. The ‘pit organs' of the sensilla coeloconica have different shapes according to species. In the apex of the male flagellum, teeth are present in the species studied but the number and shapes are different. Adjacent to the teeth is a cluster of sensilla basiconica. At high magnification, no pores were found in the sensilla walls but their more or less blunt tips have small pores. The inner face of the male flagellum can be serrated or non-serrated.     

An analysis of the swimming problem of a singly flagellated micro-organism in an MHD fluid

The present work is concerned with the study of the swimming of flagellated microscopic organisms, which employ a single flagellum for propulsion in a magnetohydrodynamic (MHD) fluid. The flow is modeled by appropriate equations and the organism is modeled by an infinite flexible but inextensible transversely waving sheet, which represents approximately the flagellum. The governing equations subject to appropriate boundary conditions are solved analytically. Expressions for the velocity of propulsion of the microscopic organism are obtained.     

The role of the liquid crystalline state in the bundling of Salmonella enterica serovar Typhimurium flagella

Salmonella bacteria owe their motility to the rotation of bundled protein filaments known as flagella. While the method by which flagella impart motility is known, there is a scarcity of data elucidating the critical process of flagellum bundling itself. This work hypothesises the process of flagellum bundling to be an energetically driven phenomenon in which a physical state transition drives the formation of the flagellum bundle at the surface of a Salmonella cell. In vitro analysis of intact flagella, detached and purified from Salmonella enterica serovar Typhimurium cells, with cross-polarised light microscopy demonstrates a transition from an isotropic to mesophasic suspension at physiologically relevant concentrations. We believe the state transition of flagellum suspensions to the liquid crystalline state directs the formation of the flagellum bundle and thus plays a role in Salmonella motility that, until this point, has been sparsely investigated.