Anna

Question 1

What is the primary target of antibiotics like β-lactams and glycopeptides?

Answer 1

Bacterial cell wall

These antibiotics inhibit the synthesis and structure of the bacterial cell wall, leading to cell lysis.

Question 2

What are the main mechanisms of action for antibiotics?

Answer 2

Antibiotics can:
* Target bacterial cell wall
* Target bacterial cell membrane
* Inhibit protein synthesis
* Interfere with DNA replication/RNA transcription
* Interfere with folate synthesis
* Cause direct damage to intracellular components

This includes action against various types of pathogens, including fungi, protozoa, and viruses.

Question 3

What is the function of fosfomycin in antibiotic therapy?

Answer 3

Inhibits the enzyme pyruvyl transferase (MurA) involved in peptidoglycan synthesis

It is broad-spectrum and primarily used for uncomplicated urinary tract infections.

Question 4

What type of bacteria does bacitracin target?

Answer 4

Narrow spectrum against a range of Gram-positive bacteria

It is used topically due to toxicity in systemic use.

Question 5

What are glycopeptides, and how do they function?

Answer 5

Glycopeptides are cell wall synthesis inhibitors that bind to D-alanyl-D-alanine in peptide chains, preventing further subunit addition

Examples include vancomycin and teicoplanin.

Question 6

What is the main characteristic of β-lactams?

Answer 6

Incorporates a β-lactam ring and binds to proteins involved in cell wall synthesis

This action inhibits the cross-linking of peptidoglycan chains.

Question 7

What are the side effects associated with penicillin?

Answer 7

Hypersensitivity reactions and diarrhea

Diarrhea is most common with broad-spectrum penicillins, which can lead to antibiotic-associated colitis.

Question 8

What distinguishes carbapenems from other β-lactams?

Answer 8

They possess a β-lactam ring fused to a 5-membered carbon ring and are resistant to most β-lactamase enzymes

They are broad-spectrum antibiotics.

Question 9

What is the only monobactam currently in clinical use?

Answer 9

Aztreonam

It is active only against Gram-negative organisms and can be administered intravenously or via inhalation.

Question 10

What is the role of mycolic acid in the cell wall of Mycobacterium?

Answer 10

It renders cells resistant to chemical damage, dehydration, antibiotics, and biocides

This contributes to the natural resistance of mycobacteria to β-lactam antibiotics.

Question 11

Name two classes of compounds that act against the cytoplasmic membrane of bacteria.

Answer 11

Peptides and lipopeptides

They disrupt membrane integrity, affecting Gram-negative bacteria.

Question 12

What mechanism do daptomycin and similar lipopeptides use?

Answer 12

Aggregate in the cell membrane to form ion channels, leading to loss of membrane potential

Daptomycin is particularly effective against MRSA.

Question 13

Fill in the blank: The cell wall of bacteria is primarily composed of _______.

Answer 13

Peptidoglycan

Peptidoglycan consists of polysaccharide chains made of N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM).

Question 14

True or False: Glycopeptides can be used orally.

Answer 14

False

Glycopeptides are poorly absorbed from the gut and are typically administered intravenously.

Question 15

What is the significance of β-lactam/β-lactamase inhibitor synergy?

Answer 15

It prevents the breakdown of antibiotics by β-lactamase enzymes

Examples include piperacillin/tazobactam and ampicillin/sulbactam.

Question 16

What types of infections are cephalosporins used to treat?

Answer 16

Septicaemia, pneumonia, meningitis, biliary-tract infections, peritonitis, and urinary tract infections

They have a broad spectrum of activity and fewer hypersensitivity reactions compared to penicillins.

Question 17

What is the primary use of polymyxins?

Answer 17

As a drug of last resort for multidrug-resistant Gram-negative infections

They can cause dose-related neurotoxicity and nephrotoxicity.

Question 18

What is the role of the cell wall in bacteria?

Answer 18

Provides structural support and protection

Question 19

What is the function of the cell membrane in cells?

Answer 19

Regulates the passage of substances in and out of the cell

Question 20

Define glycopeptides.

Answer 20

A class of antibiotics that inhibit cell wall synthesis

Question 21

What are peptides in the context of antibiotics?

Answer 21

Short chains of amino acids that can have antimicrobial properties

Question 22

What is fosfomycin?

Answer 22

An antibiotic that inhibits bacterial cell wall synthesis

Question 23

What are lipopeptides?

Answer 23

A class of antibiotics that disrupt bacterial cell membranes

Question 24

What class of antibiotics do penicillins belong to?

Answer 24

β-lactam antibiotics

Question 25

What are cephalosporins?

Answer 25

A class of β-lactam antibiotics used to treat a variety of infections

Question 26

What are carbapenems?

Answer 26

Broad-spectrum β-lactam antibiotics effective against many resistant bacteria

Question 27

What are monobactams?

Answer 27

A class of β-lactam antibiotics that are effective against gram-negative bacteria

Question 28

Fill in the blank: _______ are antibiotics that inhibit bacterial cell wall synthesis.

Answer 28

Glycopeptides

Question 29

True or False: All β-lactam antibiotics have the same mechanism of action.

Answer 29

True

Question 30

List the classes of β-lactam antibiotics mentioned.

Answer 30

• Penicillins
• Cephalosporins
• Carbapenems
• Monobactams

Question 31

Who are the authors of the textbook ‘Microbiology – An Introduction’?

Answer 31

Tortora, G. J., Funke, B. R., & Case, C. L.

Question 32

What edition of ‘Medical Microbiology’ is cited?

Answer 32

19th edition

Question 33

Fill in the blank: The textbook ‘Microbiology – An Introduction’ was published by _______.

Answer 33

Pearson

Question 34

What is the importance of studying infection and immunity?

Answer 34

Understanding how infections occur and how the immune system responds