1. KINESIN

2. Microtubules

3. Questions How much ATP is hydrolysed per step? How many rate-limiting steps are there? What is the mechanism of movement? Analyse movement Simulation of randomness

4. Michaelis-Menten kinetics v = k cat [ATP]/(Km + [ATP]) When [ATP] is limmiting: v = [ATP] k cat /Km – linear function Km: Michaelis constant: concentration of ATP at ½v max k cat : Velocity at saturatet [ATP] Kinesin: Km = 62 +/- 8 µM k cat = 680 +/- 31 nm/s At limiting [ATP]: kcat/Km = 11 +/- 1 nm s -1 µM -1

8. Randomness parameter d = step distance x(t) = position r = 0: Clock-like r = 1: 1 rate-limiting step 0 < r < 1: more ratelimiting steps r > 1: increasing variance (backwards steps, double steps, biochemically inactivatet states)