rotary motion is driven by what? How is energy created? speed?
Mot complex generates PMF, speed dependent on available PMF
Flagella structure: name 3 rings and two important proteins
L, P, MS rings, Mot protein on MS ring which drives motor, Fli proteins act as switch
how do flagella grow out/synthesized?
flagella grow from the terminus, not the base and is assembled between the cap and hook
filament is composed of what protein?
taxis: what signals do cells respond to? what pathway? Explain time variation between run/tumble cycles.
cells process environmental information through signal transduction pathway, requires a chemical gradient. Attractant-runs longer, tumbles less.
3 ways people study chemotaxis and motility
motility plates identify which ones are chemotactic, capillary tube assay, tethered cell assay to monitor time cell body spends in rotation after flagella is sheared
explain principle of adaption to stimulus in tethered cell assay
returned to baseline after responding to stimulus in order to reset so that it can receive and react again to another stimulus.
many MCP (methyl-accepting chemotactic proteins) found where? final flagellar signal?
each MCP receptor along membrane is attracted to a specific stimulus, integrated flagellar signal from all these receptors
where do MCP chemoreceptors reside?
requirements for gliding cells? edges of colonies?
filamentous or rod on solid surface. irregular edges rather than clearly defined borders of non-motile or flagellated cells.