Mathematical Biology seminar|
Department of Biology
University of Utah
"Mechanism of rod-hook length control in flagellar biosynthesis"
December 7, 2005
3:05pm, LCB 215
The bacterial flagellum is the poster child of intelligent design theorists.
Basically, it is so complicated and perfect it couldn't possibly have
evolved. The length of the flagellar rod (the drive shaft of the flagellar
motor) is intrinsic to the rod itself. The last rod structural component has
signals to control its length to be 22 nm. I will show you what happens
when we mutate that control. The hook is a flexible coupling (U-joint)
between the rod and the external rigid flagellar filament (propeller) and it
is controlled to be 55 nm +/- 5 nm in length. I will show you how a
protein, FliK, acts as a molecular ruler to determine this precise length
control for the hook. I will also describe another protein, Fluke, that
hides the design flaws to fool the intelligent design theorists in this
marvelous molecular bio-nano-machine.