Bacteria: Roles in Human Health

Question 1

Pathogen

Answer 1

A microorganism that causes sickness

Question 2

Pathogenesis

Answer 2

Process by which how pathogens cause diseases

Question 3

What are the 5 questions you should ask about Pathogenesis?

Answer 3

1. How did it get into the body?
2. Which host cell does it interact?
3. Which proteins does it bind to?
4. How does it affect the immune system?
5. What mechanism triggers the disease?

Question 4

Infection

Answer 4

Replication of a pathogen in or on the host

Question 5

Primary vs Opportunistic Pathogens

Answer 5

Primary: Those that readily causes diseases in healthy hosts

Opportunistic: Diseases that are caused in unusual locations or to immunocompromised hosts

Question 6

Case

Answer 6

Infected person with symptoms of the disease

Question 7

Asymptomatic

Answer 7

A person who doesn’t exhibit symptoms of diseases

Question 8

Who is an example of being a Asymptomatic?

Answer 8

Typhoid Mary

Question 9

Case-to-infection ratio:

Answer 9

Proportion of infected people who developed the disease

Question 10

Virulence

Answer 10

Capacity of a pathogen to cause disease

Question 11

How do pathogens cause diseases?

Answer 11

1. Entry
2. Attach/invade host
3. Evade host defenses
4. Obtain nutrients
5. Exit

Question 12

Name ways how pathogens can be spread through direct human contact.

Answer 12

1. Blood
2. Air
3. Sex

Question 13

Name ways how pathogens can be spread through indirect human contact.

Answer 13

1. Food
2. Water
3. Fomite Objects
4. Insect Bites
5. Animals

Question 14

Explain Virulence Factors

Answer 14

Molecules or behaviors by a pathogen that contributes to its pathogenicity

Question 15

How is the Host Range determined for pathogens?

Answer 15

Group of organisms the pathogen is able to infect

Question 16

What are the challenges of Virulence Factors of Pathogens?

Answer 16

1. Attachment
2. Penetration of intact skin
3. Resisting antibacterial peptides
4. Escaping antibodies
5. Evading Phagocytes

Question 17

Molecules and Behaviors for intact skin

Answer 17

Molecules: None
Behaviors: Survive on skin and insect bites

Question 18

Molecules for resisting antibacterial peptides

Answer 18

Molecules: -charged LPS in outer membrane, peptidases, and counter proteins for peraurablizing effects of channels

Question 19

Molecules and Behaviors for escaping antibodies

Answer 19

Molecules: IgA proteases
Behaviors: Antigenic Variation and Camouflage with host proteins

Question 20

Molecules for evading phagocytes

Answer 20

Catalase

Question 21

A-B toxins are what?

Answer 21

Protein Subunits

Question 22

A does what?

Answer 22

Enzyme Active

Question 23

B does what?

Answer 23

1. Binds to Membranes
2. Specific Cell-Surface
3. Cell Receptor induces endocytosis

Question 24

When A-B are internalized what happens?

Answer 24

2 protein subunit must escape the endosome to reach its cellular target

Question 25

Explain further what happens to A-B

Answer 25

1. H+ pumps reduce eadosomal ph 2. Acidification causes A-B to dissociate A. B forms channel B. A exits through the channel and enters the cytoplasm

Question 26

Botulinum Toxins explain the two ways how they can be deadly.

Answer 26

``` 1. Snare Proteins A. Acetycholine secreted B. Muscle Contraction 2. Snare Proteins A. Acet. not secreted B. Flaccid Paralysis ```

Question 27

Tetanus Toxins explain the two ways how they can be deadly.

Answer 27

``` 1. Synaotibrevin A. Glycine or GABA secreted B. Acet. not secreted C. Muscle contraction halted 2. Synaotibrevin A. Glycine or GABA not secreted B. Acet. secreted C. Spastic Paralysis ```

Question 28

Shiga Toxin explain how they can be deadly.

Answer 28

1. rRNA to make protein synthesis | 2. Not normal cannot do protein synthesis

Question 29

Cytolysins are what?

Answer 29

Enzymes that act on the host cell membrane | Ex: Lysis

Question 30

Cytolysins functions

Answer 30

1. Pore-formation | 2. Phospholipid degradation

Question 31

Endotoxins

Answer 31

Toxins that are part of Gram -cell membrane structure that induce inflammation of host cells.

Question 32

Most common endotoxin

Answer 32

Lipopolysaccharide (LPS)

Question 33

How are endotoxins released and where are they found?

Answer 33

Lysis of the bacteria cell and toll-like receptors mammal cells

Question 34

What acid has very similar functions to endotoxins, but aren't endotoxins?

Answer 34

Lipoteichoice acid