MICRB265 Lecture Notes - Lecture 18: Organelle, Magnetotaxis, Magnetite

• School: University of Alberta
• Department: Microbiology (Biological Sciences)
• Course: MICRB265
• Professor: Perrin Beatty

Document Summary

Flagella in gram negative bacteria tiny helically shapes, rotating machines. attractions between pos and neg charges causing rotation. Many components; filament flagellin, hook hook protein, basal body. Rotor central rod, l, p, ms, and c rings which make up basal body. Stator most proteins generate torque, 1200 protons translocated per rotation. H+ exert electrostatic forces on helically arranged charges on rotor proteins with alternating. Fil proteins motor switch, switch direction of motor. Move by rotation but energy is from atp instead of pmf. Filament proteins with little homology to bacterial flagellin. Movement typically occurs away from the colony, and requires surface contact. Some domain bacteria can do gliding motility or twitching motility. Bacteria move towards or away from physical or chemical gradient, called taxis, depending on whether it is a nutrient or energy source of harmful substance. Chemotaxis, phototaxis, scotophobotaxis, aerotaxis, magnetotaxis (example m. Run smooth forward motion, flagellar motor rotates counterclockwise.