Motility

Question 1

Taxes

Answer 1

Tactile responses

Question 2

Flagella general structure

Answer 2

Basal body + hook + filament

Question 3

Types of flagellum arrangement

Answer 3

Peritrichous and polar

Question 4

Peritrichous

Answer 4

Multiple flagella arising from along the cell body in a uniform distribution

Question 5

Lophotrichous

Answer 5

several flagella that are all present at the same place on their surfaces and work together to propel the bacteria in a certain direction

Question 6

What proteins make up the filament?

Answer 6

Flagellin and FliC

Question 7

Flagellin

Answer 7

globular protein that arranges itself in a hollow cylinder to form the filament in a bacterial flagellum
Subunit also know as FliC

Question 8

Rotor

Answer 8

C-ring, MS ring, rod, hook

Question 9

Stator

Answer 9

MotAB, P and L ring - hold rotor in place

Question 10

C-ring

Answer 10

Made up of 3 proteins
FliG, M, N
Part of stator complex

Question 11

FliC

Answer 11

Inside of rod and moves up and assembles on surface of growing filament

Question 12

How many protons are required for a 360 degree rotation?

Answer 12

300

Question 13

Switch complex

Answer 13

C-ring
Controls direction of rotation

Question 14

IMF

Answer 14

Ion motive force

Question 15

Protonation in MotB

Answer 15

Both protonation and deprotonation of MotB-Asp33 induce conformational changes of the cytoplasmic loop between TM2 and TM3 of MotA (MotAC), which is directly involved in the interaction with FliG

Question 16

Power stroke

Answer 16

After the initial electrostatic steering, two protons bind to thecharged Asp32 residues on the MotBs. The consequent rearrangement of hydrogen bonds induces an elastic strain in the straight MotA loops. Release of thisstrain results in synchronous kink and swivel motions about the proline hinge in both MotAs. As a result, a steric push is imposed on FliG, and the first half ofthe power stroke is performed by loop 1. Importantly, this motion also has a vertical component—the loops lower themselves out of the membrane. (Bottom)The lowering of the MotA loops exposes the protons in MotB to the cytoplasm, whereupon they are released. This results in a reset of the MotA loops, duringwhich loop 3 carries out the second half of the power stroke. We note that this image depicts a 2D projection of a 3D motion: The motion of the stators is notconstrained to the plane of the page. An observer sitting on the rotor axis sees the stator inchworm walking along the rotor using the FliGs as steppingstones.

Question 17

CW vs CCW

Answer 17

CheY phosphorylated in CW and unphosphorylated in CCW

CheY interacts w rotor

Question 18

Smooth swimming

Answer 18

CCW
Flagella bundle together
Straight line

Question 19

Tumbling

Answer 19

CW
Flagella peritrichous
Random movement + dictates change in direction

Question 20

Random walk

Answer 20

Switching between CW and CCW

Question 21

Biased walk

Answer 21

CCW for longer towards attractant

Question 22

MCP

Answer 22

Methyl accepting chemotaxis protein