Lecture 5: Surface of Microbial Cells Flashcards
what is the S layer?
outer layer of the cell envelope
what is the S layer composed of?
permeable lattice made of proteins
Bacteria vs Archaea cell wall
Bacteria- made of sugar
Archaea- made of proteins
what is the S layer function in Bacteria vs Archaea
Bacteria- protection & adhesion
Archaea- protect against osmotic lysis & cell shape
where is the S layer found in gram negative bacteria?
on top of outer membrane
does gram negative bacteria have a S layer?
no
what is the function of the capsule & slime layer
protection
what is the difference between the capsule & slime layer?
Capsule- strongly attached
Slime layer- loosely attached
what is the function of conjugative pilus?
allows communication between bacteria through horizontal gene transfer
what group is hami unique to?
SM1
what is the function of hami?
attachment & biofilm formation
petrichious flagella
flagella all around the cell
polar flagella
1 flagella at 1 end
Lophotrichous
multiple flagella from 1 end
amphitrichous
1 flagella at each pole
how does pertrichious flagella move?
tumbles
how does polar flagella move?
moves unidirectional & in straight line
how do flagella assemble?
from the tip
what type of secretion are flagella?
type 3
what type of secretion are archaella?
type 4
how do archaella assemble?
from the base
difference in energy movement flagella vs archaella?
flagella- PMF
Archaella- ATP
is flagella or archaella faster?
flagella
what domain twitches & glides to move?
bacteria
main difference between twitching & gliding?
twitching- uses ATP
gliding- uses PMF
if taxis move towards a stimuli, what does that mean?
it is positive
what is chemotaxis?
surface proteins that send input to flagella
when there is no attractant present, what does that mean for the movement?
it moves randomly
what is the source of energy for the flexible whip?
ATP
