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ORAL MICROBIOLOGY > Lecture 4 - Pili, Fimbriae, and Flagella > Flashcards

Lecture 4 - Pili, Fimbriae, and Flagella Flashcards

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1
Q

Genus of bacteria that does NOT have a cell wall

A

Mycoplasma

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2
Q

Since they don’t have a cell wall, Mycoplasma are resistant to

A

a lot of antibiotics such as penicillin -

Antibiotics which target cell wall formation (are ineffective against them)

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3
Q

____ Have a size limiation - big molecules cannot pass - very large particles require vesicular transport out of cell

A

PORINS

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4
Q

If Protein 1 is knocked out of the ABC Transporter, where will the compound be accumulated?

A

In the periplasm

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5
Q

What does the ABC Transporter stand for?

A

ATP Binding Cassette

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6
Q

To secrete enzymes or toxins outside of the bacterial cell, bacteria use

A

secretion systems (I-VI)

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7
Q

What is secretion system VII

A

only used for microbacteria - recently discovered.

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8
Q

Which secretion systems need porins in order to be active?

A

System II bacteria secrete preoteins using Sec and TAT system then they must use a porin to get into the cell

System V is an autotransporter - it builds its own porin while it transports its peptide

System VI the outer porin is not a porin but an actual part of the secretion system

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9
Q

if toxin goes through system I and knocks out all the porins in the membrane, will it still be able to secrete?

A

YES BEcause SYSTEM I DOES NOT USE PORINS

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10
Q

SECRETION SYSTEM I

A

This system’s structure is like the ABC transporter structure. There is usually a signal sequence at the C-terminus of protein, which is like the “passcode” that allows protein to exit through this system.

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11
Q

This system’s structure is like the ABC transporter structure. There is usually a signal sequence at the C-terminus of protein, which is like the “passcode” that allows protein to exit through this system.

A

SECRETION SYSTEM I

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12
Q

SECRETION SYSTEM Il

A

This system requires porins and secretes Pili

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13
Q

This system requires porins and secretes Pili

A

SECRETION SYSTEM Il

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14
Q

SECRETION SYSTEM Ill

A

Directly secretes into the cell mammalian cell. Like a syringe, it binds to its target cell and injects its compounds

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15
Q

Directly secretes into the cell mammalian cell. Like a syringe, it binds to its target cell and injects its compounds

A

SECRETION SYSTEM Ill

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16
Q

SECRETION SYSTEM IV

A

Some go through Sec or TAT, some go in directly

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17
Q

Some go through Sec or TAT, some go in directly

A

SECRETION SYSTEM IV

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18
Q

SECRETION SYSTEM V

A

Juvenile periodontitis, autotransporter, builds its own porin. Signal sequence allows it to go through Sec/Tat of inner membrane. The beta domain forms the barrel part of the porin, while the passenger domain sticks out like a flag

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19
Q

Juvenile periodontitis, autotransporter, builds its own porin. Signal sequence allows it to go through Sec/Tat of inner membrane. The beta domain forms the barrel part of the porin, while the passenger domain sticks out like a flag

A

SECRETION SYSTEM V

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20
Q

SECRETION SYSTEM Vl

A

This is like system III but II allows bacteria to move things into mammalian cell - System VI is more for bacteria - bacteria transfer

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21
Q

This is like system III but II allows bacteria to move things into mammalian cell - System ____ is more for bacteria - bacteria transfer

A

SECRETION SYSTEM VI

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22
Q

Outer membrane vesicles

A

Lets say toxin gets into the periplasmic space through TAT or SEC. Outer membrane pinches off a vesicle which detaches from the cell. the cell will rebuild the outer membrane.

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23
Q

Which secretion systems are utilized by Pseudomonas (cause of lung infection in people)

A

Type I, II, III systems) Also OUTER MEMBRANE VESICLES

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24
Q

How do bacteria store excess carbon?

A

We humans have fat, if you give a person an excess of a carbon it will be converted to fat.
For bacteria, their storage compound is sugar - PHA’s and GLYCOGEN
PHA = poly-beta-hydroxyalkanoates

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25
Q

What is PHA?

A

PHA = poly-beta-hydroxyalkanoates

Storage polymers in presence of excess carbon. Bacteria store these carbs in granules within the cytoplasm. PHA has same properties as polypropylene so you can make bioplastics out of bacteria!

Bacteria can fix nitrogen - this bacteria produces a plant hormone called oxin (A. brasilense) this oxin helps roots of plants grow bigger.

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26
Q

Bacteria can fix nitrogen - this bacteria produces a plant hormone called _______ which helps roots of plants grow bigger.

A

oxin (A. brasilense)

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27
Q

What is PHA-Z?

A

enzyme that breaks PHA into CO2 and water which is food for bacteria. They can use this process in times of starvation

If we grow bacteria in poor media and also knock out enzyme that makes PHA, IT WILL NOT GROW WELL - IF IT STILL HAS THE ABILITY TO MAKE AND USE PHA IT HAS BETTER RATE OF SURVIVAL.
NOT IMPORTANT IN PATHOGENESIS SINCE WE HAVE ABUNDANCE OF NUTRIENTS FOR BACTERIA.

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28
Q

What happens If we grow bacteria in poor media and also knock out enzyme that makes PHA,

A

IT WILL NOT GROW WELL - IF IT STILL HAS THE ABILITY TO MAKE AND USE PHA IT HAS BETTER RATE OF SURVIVAL.

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29
Q

Polyphosphate is ?

A

Another element that is vital for bacteria - needed to build DNA

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30
Q

Metal granules in bacteria contain magnetite. Aquatic bacteria use this to tell which direction is up or down, thus orienting themselves. Again not important for pathogenesis in HUMANS.

A

MAGNETOSOMES

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31
Q

Is PHA IMPORTANT IN PATHOGENESIS

A

NOT IMPORTANT IN PATHOGENESIS SINCE WE HAVE ABUNDANCE OF NUTRIENTS FOR BACTERIA.

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32
Q

Aquatic bacteria use this to float (buoyancy) for example to stay in surface waters containing more oxygen

A

GAS VESICLES

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33
Q

This is important for pathogenesis - most organisms in nature can spread themselves in time and space (movement) Bacteria have pili and flagella to spread themselves through space . Trees cannot do this although their seeds can - spreading in time means going to sleep, going into a dormant state until environmental conditions become better. We can’t do that but some animals can hibernate. Plant seeds which are dormant, bacteria have spores.

A

ENDOSPORES

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34
Q

Usually if conditions are good, replication occurs and you get 2 cells, when conditions are bad, DNA will replicate but will be covered by _________

A

peptidoglycan and calcium (dehydrated structure)

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35
Q

Only ______ can produce SPORES

A

GRAM POSITIVE but not all GRAM + do!

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36
Q

High pressure lets you reach a high enough temperature (AUTOCLAVE) in the clinic _____ is required to kill bacteia

A

60-80 degrees celcius

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37
Q

____ Temperature is used to pasteurize milk

A

55 degrees

that is why milk spoils eventually - still spores in there

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38
Q

_____ DEGREES WILL KILL VEGETATIVE STATE AND SPORES

A

120 degrees CELCIUS

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39
Q

Do Bacillus anthracus produces spores?

A

YES - Gram positive bacteira which is so resilient to environment can be used as bioweapon.

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40
Q

How do we make spores?

A

put bacteria in unfavorable environment to induce production of spores.

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41
Q

How long can spores last?

A

Hundreds of years!

EX: tetanus and botulism are both caused by spore making bacteria.

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42
Q

Why are certain cans inflamed

A

Anaerobic bacteria inside cans produce the gas METHANOL

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43
Q

Clostridium difficile (C. diff) usually doesn’t attack humans because normal flora of the GI tract prevent it from getting out of control. If you take high doses of antibiotics, the normal flora is not there and the spores of C. diff ____

A

cause an infection. Sometimes that part of intestine must be surgically removed.

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44
Q

If you give a person high doses of antibiotics, ____ can proliferate too much leading to

A

YEAST

CANDIDIASIS INFECTION in the mouth

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45
Q

It is not enough to use alcohol sanitizers in the clinic because

A

ehtannol breaks the bacterial cell membrane thus dehydrating the cells but that kills only bacteria - not spores. you need BLEACH to kill spores.

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46
Q

What is needed to kill spores?

A

BLEACH

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47
Q

What is germination?

A

When bacteria spores start growing into bacteria in vegetative state

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48
Q

__, ___, and ____ are important for pathogenesis (developing disease)

A

PILI
FIMBRIAE
FLAGELLA

ALL VIRULENCE FACTORS

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49
Q

Fimbrae means ____ in latin

A

thread or fiber

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50
Q

Pili means

A

hairlike

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51
Q

There is a greater number of ____ than ____ (Fimbria,pili,flagella)

A

there is a greater number of FIMBRIAE than PILI

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52
Q

____ look like a fuzzy coat of hair all over the cell

A

FIMBRIAE

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53
Q

___ are longer and thicker than _____ and there aren’t as many on the cell
(Fimbria,pili,flagella)

A

PILI are longer and thicker than FIMBRIAE and there aren’t as many on the cell

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54
Q

Are pili and fimbria formed from different genes?

A

One a genetic level, FIMBRIAE and PILI are formed from DIFFERENT GENES
Usually genes for fimbriae are on chromosome
Genes for pili could be on plasmid (DNA that replicates separately from chromosome)

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55
Q

What is a plasmid?

A

DNA that replicates separately from chromosome

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56
Q

Where are genes for pili?

A

On plasmid (DNA that replicates separately from chromosome)

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57
Q

Where are genes for fimbriae?

A

On chromosome

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58
Q

The _____ codes for the sex pili

A

F plasmid

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59
Q

Type 1 pili is

A

a fimbriae

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60
Q

What is the role of fimbriae

A

to attach bacteria to host cells (epithelial cells, other bacteria) in addition, because they stick out they are very antigenic. you invoke immune response by injecting just the fimbriae. they are important virulence factors - without them, bacteria cannot colonize/infect - so if you knock out gene that makes fimbriae, you can make bacteria non-virulent

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61
Q

Without fimbriae bacteria cannot

A

colonize or infect

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62
Q

What is pilin

A

protein that composes pili

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63
Q

Type 1 pili is an adhesive pili because

A

it contains receptors at the tip which can bind to host cells.

64
Q

On our cells we have glycoproteins that are specific to the individual. The ____ receptors located on pili can bind to glycoproteins and adhere to host cell

A

LECTIN RECEPTORS

65
Q

Why do people claim that drinking cranberry juice can get rid of UTI?

A

Idea that the sugar in cranberry juice binds E coli’s pili receptor. this would prevent bacteria from binding to host cells thus stopping UTI. The problem with doing this is therapeutically you must drink a LOTTTTT and so much sugar is problem too

66
Q

What is a clinical example which uses Type I pili to attach to tissue and cause infection.

A

N. gonorrhoeae

Sexually transmitted GRAM NEGATIVE DISEASE

67
Q

N. gonorrhoeae

A

GRAM NEGATIVE
Sexually transmitted
Doctor’s put white cream (antibiotic) on newborn baby eyelids in case the mother has gonorrhea infection (one of leading causes of blindness in babies)

68
Q

Pili is antigenic and that is not good news for bacteria because

A

HOST CELLS CAN RECOGNIZE IT EASILY

69
Q

How do you counter the antigenicity of PILI?

A

PILI HAS MUCH GENE/ANTIGENIC VARIATION. If bacteria normally use PilE gene to make pili, bacteria can switch to a different gene, PilS (and there are 19 variations of PilS). This makes it sothat the antibodies we make for PilE will not detect PilS pili.

70
Q

What is the effect of bacteria switching to use gene PilS instead of PilE?

A

Bacteria normally use PilE gene to make pili
if they switch to PilS gene, there are 19 VARIATIONS OF PilS - this makes it so that the antibodies for PilE pili will not detect the PilS pili

71
Q

What happens to virulence capabilities if you continue plating bacteria in the lab?

A

It will lost virulence capabilities due to mutations and no necessity for using it. Sometimes the loss is due to phase variation.

72
Q

Recall that to extend pili out of cell, what system do bacteria use?

A

Type II secretion system

73
Q

How do bacteria control the pili

A

To extend pili out of the cell bacteria use the Type II secretion system - Bacteria can control this process by turning on/off the pili gene. They can turn off the secretory protein which will also affect the presence/absence of the pili.

74
Q

Pili helps produce ______ of dental plaque and helps aggregation with each other and surfaces.

A

biofilm

75
Q

Type I pili can cause what

A

Huge aggregates and produce an EPS. In a test tube you will see huge clump of biofilm , the faster it sinks the more cells you have.

76
Q

How do bacteria arrive on a surface?

A

Via gravity or flagella

77
Q

There are 2 stages the reversible stage and irreversible stage of bacterial attachment to surfaces. Describe both

A

REVERSIBLE STAGE: when bacteria arrive and detach

IRREVERSIBLE STAGE: when bacterial cell makes a strong connection via the pili with the surface.
Bacteria start producing EPS and more cells form microcolonies.
More bacterial cells arrive (late colonizers) and attach to initial colonizers (have mechanism to form pili) Mature biofilm allows cells to detach adn move to other areas. Surface can be abiotic, biotic, and they can be other bacterial cells

78
Q

What is the pellicle?

A

saliva proteins that cover teeth - this is actually what pili attach to, not enamel

79
Q

If you plate Aa, it will form pili with agar plate. If you continue plating what will happen to bacteria?

A

They will lose pili and be easily detached (Flp-1 mutant does not form pilus - cannot autoaggregate, cannot form biofilm)

80
Q

What is the Flp mutant?

A

No Flp pili - no attachment - no disease

81
Q

Bacteria forms biofilm and immune system tries to fight back - what is the result of the immune response?

A

Bone resorption

While bacteria do not actually break down the bone, the resoroption is a good indicator of bacterial infection

82
Q

What are type IV pili?

A

Type IV pili can go in and out of the cell wall. It is built from pilin monomers from the base (close to the membrane) and goes outward. Bacteria can either bind or cleave pilin monomers of the cahin so this causes extension and retraction.

83
Q

What motility do Type IV pili use?

A

Twitching motility, via occlusion or through saliva

84
Q

What is Twitching motility?

A

Type IV Pili are located at one or both poles of the cell. On a semi-solid surface bacteria can stick to a site on the surface and then decrease the pili length thus sliding itself across the surface. One way bacteria can travel throughout the oral cavity is through salive, through contact (occlusion) or through twitching motility

85
Q

What is conjugative pili

A

Also known as Sex pili - this pili is extracted from donor bacteria, it binds to the recipient bacteria and pull it is. Pili have receptors of prortein and phages lik to attach to it. So the sex pili is not actually that thick.
Phages can enter the cell when the pili gets pulled in. Type IV F plasmid codes for this pilus. After retraction of the pilus, bacteria cells fuse and conjugate. Conjugation is when they copy and pass plasmids to each other thus conferring resistance.

86
Q

What are pili made from?

A

Protein called pilin

87
Q

Type I pili are actually called

A

fimbriae

88
Q

What are lectins?

A

Receptors that bind sugars on our cells. They bind to glycoproteins on our cells in order to identify them as self

89
Q

Receptors that bind sugars on our cells. They bind to glycoproteins on our cells in order to identify them as self

A

Lectins

90
Q

What is phase variation?

A

The concept that bacteria have several phenotypes depending on their environment (Ex: loss of virulent factors when in the lab)

91
Q

Pili are important in binding but are very antigenic, so this is a problem for bacteria. N gonorrhea overcomes this problem how?

A

By changing the proteins it uses to make the pili.
Usually PilE is used but the bacteria has another subset of genes that make the same protein but slightly modified. The bacteria can switch the genes used to make the pili to PilS genes. This results in different antigenicity so it is difficult for the body to produce sufficient antibodies quickly enough, this is known as ANTIGEN VARIATION

92
Q

Does Vibrio cholera have a pili?

A

Yes it allows it to form biofilms in the gut but in the environment, it attaches to plants with a different kind of pilus. Produces 2 different pili types to attach to two different surfaces. ANTIGEN VARIATION

93
Q

What is an aggregation assay?

A

faster bacteria can get to the bottom the more aggregates you have

94
Q

When you grow Pseudomonas aureginosa (GRAM NEGATIVE) it produces

A

type I pili and forms aggregates with an EPS (floating biofilm)

95
Q

Biofilm formation is facilitated by

A

PILI

96
Q

What are TYPE IV PILI?

A

Pili that can go in and out, built from bottom up. The pili can be cleaved to start by bringing them inside.

97
Q

_____ is a movement mediated by TYPE IV pili that go in and out if there is a surface that is semisolid.

A

TWITCHING MOTILITY

98
Q

To measure or examine twitiching motility, do what?

A

put bacteria underneath agar, so that there is plastic below them and agar above them, if they move along the bottom, that is twitching motility

99
Q

what is standard agar on a plate?

A

1.5% agar

100
Q

Sex pilus is also called the

A

conjugation pili AKA - TYPE IV PILI

101
Q

What does the F plasmid code for?

A

Type IV pili

102
Q

A resistance plasmid can be transferred through

A

conjugation

103
Q

Conjugation and movement of plasmids happens a lot inside of ____

A

biofilm where bacteria are close

104
Q

The F plasmid codes for the sex pilus. BActeria with this plasmid are DONORS they attack

A

other bacteria called recipients via the pilus and put it in. They can now transfer the plasmid to the recipient and recipient can become a donor and can for the sex pilus as well.

105
Q

___ are for moving on semisolid surfaces and are involvved in attachment

A

PILI

106
Q

___ are antigenic and conserved and also have a role in attachment. Involved in the movement of bacteria as well.

A

FLAGELLA

107
Q

Flagella are encoded by different genes THAN FIMBRIAE AND PILI. How else to they differ structurally?

A

They are much longer and there are less of them

The flagella could be 50x longer than length of bacteria

108
Q

Flagella on one side of the cell

A

SINGLE POLAR

109
Q

flagella on each end of the cell

A

BI POLAR

110
Q

Flagella in tufts

A

POLAR IOPHOTRICHOUS

111
Q

Flagella all over

A

PERITRICHOUS

Ex: E.coli or Salmonella

112
Q

The flagella system is one of the smallest and most efficient engines ever created. Describe why

A

The basal body can spin up to 17,000 RPM
The flagella itself can spin up to 1000 rpm
Can go in reverse unlike an engine
Flagella can also stop
Flagella can propel bacteria as fast as 100x their body length per second.

113
Q

What is the structure of flagella?

A

40 proteins
BASAL BODY - anchored in the cell wall
ROTOR - part that spins
in the outer membrane are a few rings
the FLAGELLA HOOK binds the flagella to the big basal body
Stator - consisting of MOD A and MOD B proteins

114
Q

If you knock out the stator (consisting of Mod A & Mod B proteins) will bacteria have flagella?

A

Yes bacteria will still have flagella - it wont be able to spin, but it will be there and it will still be antigenic.

115
Q

If you knock out the hook, will bacterium still have flagella?

A

No will no longer have flagellum if you knock out hook. will no longer be antigenic

116
Q

Flagellar Synthesis Explain

A

The inner structure is built first, then the flagellar proteins are squeezed out.
Flagella consists of a filament, hook, and basal body.
The stator is attached to the peptidoglycan layer. Does not orate - each stator has 2 mot b proteins and 2 mot a proteins.
Protons move through the channels in the stator. They bind to mot a protein inducing the first power stroke to move the rotor.
The unbinding of the protonsdrive the second power stroke.
The rotor rotates

117
Q

Are there rings in the outer membrane of flagella in Gram Positive bacteria?

A

IN GRAM POSITIVE BACTERIA, WE DON’T HAVE RINGS IN THE OUTER MEMBRANE SINCE THERE IS NO OUTER MEMBRANE

118
Q

Can flagella change directiON?

A

Flagella can stop and change direction
ccw forward
cw backward

119
Q

If there are multiple flagella bacteria can go through a movement called

A

tumbling in which flagella spin in difgferent directions allowing bacteria to stay in the same place before changing directions.

120
Q

If the flagella can move cw or ccw it will all go in

A

one direction

121
Q

Flagella are important in swimming motility. This differs from twitching in that

A

twitching occurs on semi solid surfaces .
swimming occurs on liquid surface. if you make an agar plate have more liquid consistency, you can observe bacteria move. In the center of the plate is inoculated with bacteria it will spread outward if they can swim.

122
Q

If you knock out the flagella and inoculate a plate with bacteria in the center, what will happen

A

They will stay in the center of the medium since they cannot swim

123
Q

Do cells within biofilm have flagella?

A

Cells within biofilm lose their flagella since they don’t need it unless conditions get bacd in which they are forced to move. Under those conditions, some bacteria start producing the flagella.

124
Q

What is swarming motility?

A

Mediated by the flagella in a semiliquid surface. Bacteria secrete surfactant, which is a slimy layer that usually contains lipid. It is a kind of soap that they can glide on with the movement of the flagella.

125
Q

What is surfactant?

A

Bacteria secrete surfactant, which is a slimy layer that usually contains lipid. It is a kind of soap that they can glide on with the movement of the flagella.

126
Q

What is gliding motility?

A

Some gram positive bacteria don’t have flagella they move by gliding motility. It is like swarming but without flagella. They produce surfactant they can glide on.

127
Q

WHat is phototaxis?

A

Positive toward light

negative away from light

128
Q

What is chemotaxis

A

Positive - move toward where a nutrient gradient is higher

negative - move away from a toxin

129
Q

MOVE AWAY FROM A TOXIN

A

NEGATIVE CHEMOTAXIS

130
Q

MOVE TOWARD WHERE A NUTRIENT GRADIENT IS HIGHER

A

POSITIVE CHEMOTAXIS

131
Q

MOVE TOWARD LIGHT

A

POSITIVE PHOTOTAXIS

132
Q

MOVE AWAY FROM LIGHT

A

NEGATIVE PHOTOTAXIS

133
Q

MOVE AWAY FROM OXYGEN

A

NEGATIVE AIROTAXIS

134
Q

What is negative airotaxis?

A

away from oxygen, important for anaerobic bacteria that can’t tolerate the free radicals generated by oxygen.

135
Q

Bacteria move toward a gradient through a series of starts and stops. They move in one direction, pause see if they are on the right track, and alter their direction accordingly, This movement is a mixture of

A

forward movement, and tumbling

sometimes they make errors in the direction of their movement

136
Q

Some proteins are involved in bacteria’s ability to sense the environment. Proteins on the surface of the bacteria bind to a specific attractant triggering …

A

signal transduction pathway that will eventually affect the flagella intracellularly to make it rotate in one direction or another.

137
Q

How do you measure phototaxis?

A

Classic way to measure phototaxis is to:

  • Take a vessel with bacteria and put into tube with something inside, more bacteria will go inside the tube relative to the surrounding environment if there is attraction. If compound in the tube is repellent, cells wont go inside and there will be less bacteria in the area than you would expect.
  • If NEUTRAL - bacteria go in and out until the concentration outside and inside are roughly equal

ANOTHER WAY IS THROUGH MICROSCOPY - cover surface of a glass put bacteria in and bind flagella to surface and tag them with antibody if you put in an attractant or repellent flagella will spin a certain way depending on which it is and you can also tag entire bacteria with FLUORESCENT PROTEIN AND WATCH THEM MOVE ALSO

138
Q

What are axial filaments?

A

Some flagella are in the periplasmic space and are called endoflagella. When these flagella move, the bacteria move like a corkscrew, this is characteristic of spirochetes. Some spirochete species can be found in the oral cavity (treponema denticola)
ENDOFLAGELLA ARE OFTEN FOUND IN GRAM POSITIVE BACTERIA

139
Q

Where are endoflagella generally found?

A

Gram positive bacteria.

140
Q

Some bacteria move themselves with ____ in the periplasmic space

A

ENDOFLAGELLA

141
Q

Endoflagella bacteria have no _____

A

outer membrane ring section of the stator

EX: SPirochetes are twisted because of their endoflagella - They are found in periodontal disease, T. denticola

142
Q

Airotaxis

A

oxygen makes free radicals, anaerobic bacteria move away from oxygen

143
Q

Phototaxis

A

moves towards light

144
Q

chemotaxis

A

moves from low gradient of nutrients to high gradient

145
Q

osmotaxis

A

gradient of osmolarity they can move ot low gradient away from high salt.

146
Q

twitching motility

A

occurs on SEMI SOLID 1.5 % AGAR

147
Q

Swimming motility

A

occurs on liquified surface. If you use 0.3 % agar - “goo” it is liquidy and can let you view swimming motility. Swimming allows cells to get away from biofilm, though most cells in biofilm don’t have flagella (not needed)

148
Q

Swarming motility

A

occurs on semi liquid surface plate on 1.5 % agar that is moist. Bacteria produces a slimy liquid surfactant that allows it to glide across a surface.

149
Q

What is peritrichous flagella?

A

Bundled flagella rotate counterclockwise - they tumble when the flagella push apart in different directions thus orienting the bacteria in a different direction. WHen tumbling they essentially hover.

150
Q

What is unidirectional flagella?

A

Bacteria propels, stops and reorients, and then propels in a different direction

151
Q

MAIN PARTS OF FLAGELLA

A

filament
hook
basal body - where the engine is (made of stator & rotor)
Stator - stationary - provides energy to spin (mot A and mot B)
Rotor - actually spinning component made of 4 rings L ring, P ring, MS ring, C ring

152
Q

How does flagella work?

A
  1. Hook binds the flagella to the basal body

2.

153
Q

If i knock out stator

A

bacteria will still have flagella and be antigenic

154
Q

if i knock out hook

A

it will not be antigenitc because you lose the antigenic flagella

155
Q

E coli strain called 015787 very aggressive caused

A

Taco bell lettuce outbreak

156
Q

Flagella is built from

A

the base. so proteins are squeezed through the cell embrane and added to the bottom of the growing flagella

157
Q

2 rings in the outer membrane are only present in

A

Gram negative because gram positive has no outer membrane

ORAL MICROBIOLOGY (5 decks)

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