Antibiotics

Question 1

What is the issue with antibiotic resistance

Answer 1

The biggest current threat to medical science

Question 2

What is antibiotics mode of action

Answer 2

Antibiotics can either be:
Bactericidial - killing bacteria
Acteriostatic - inhibit bacterial pathogens

Question 3

Where do bacteria attack

Answer 3

Genome
Cell wall
Cell membrane
Ribosomes

Question 4

How many different classes of antibiotic are there

Answer 4

Over 15
They are classed to similar strucutre etc

Question 5

What are b-lactam antibiotics defined by

Answer 5

B-lactam ring

Question 6

What are the examples of b-lactam antibodies

Answer 6

Penicillin, ampicillin

Question 7

What is the mode of action of b-lactam antibodies

Answer 7

Inhibition of cell wall synthesis

Question 8

What do b-lactam antibiotics aim to do to penicillin-idling proteins

Answer 8

Aim not to bind penicillin
These PBP proteins in peptidoglycan cross-linking transpeptidases and carboxypeptidases are key

Question 9

What happens wen penicillin interacts with penicillin binding proteins

Answer 9

Little cross linking
Weaken cell walls
Osmotic pressure
Induction of autolysis pathway

Question 10

What are examples of tetracyclines

Answer 10

Oxytetracycline, doxycycline

Question 11

What are tetracyclines defined by

Answer 11

4 ring struute

Question 12

What is the mod of action of etracyclines

Answer 12

Inhibitionn of protein synthesis

Question 13

How do tetracyclines inhibit protein synthesis

Answer 13

Target16s rna n the 30s subunit - increases retinoids acid signalling

Question 14

What are the side effects of tetracyclines

Answer 14

Anti-inflammatory - does more than one thing excellent

Question 15

Examples of quinolones

Answer 15

Nlidixic acid

Question 16

What are quinolones defned by

Answer 16

Central 2 ring strucutre

Question 17

What is the mode of action of quinolones

Answer 17

Interference with DNA gyrase which is critical in DNA replication
Prevents supercoiling of dna

Question 18

What are b lactams used to treat

Answer 18

Strangles
Streptococooola and colostridial infections
Mastitis

Question 19

What do quinolones treat

Answer 19

Erfloxacin for poultry
E,coli, oampylobacteria

Question 20

How does antibiotic resistance develop

Answer 20

• natural resistance in bacterial populations mutation occurring due to low treatment level
  Acquired by plasmids from other bacteria/species

Question 21

What causes B-lactam resistance

Answer 21

Increase production of PBP antibodies
Express decoy PBP
Mutations in PBP proteins - stop penicillin from binding but allows it to function
Stop cross linking within peptidoglycan wall

Question 22

What are b-lactamases

Answer 22

Proteins encoded on bacterial plasmids or hormones

Question 23

What examples of gam positive bacteria are b-lactamases on

Answer 23

S,aureus

Question 24

How do we get aorund b-lactamses resistance

Answer 24

Create b-lactam inhibitors - allows antibiotic t function as they target the protective mechanism

Question 25

What causes tetracycline antibiotic resistance

Answer 25

Send as gowhtpromoters until 2017 - we dont need it anymore as nutrition fattens animals
Causes resistant mechanisms- found by gene testing
Protective proteins bloc action against ribosome meaning drug can no longer reach the ribosome