class #5- antibiotics and resistance

Question 1

what is an antibiotic

Answer 1

a compound known to exhibit growth-inhibiting properties, they are chemical and biological compounds

Question 2

what is antibiotic resistance

Answer 2

The ability of an organism to grow and/or exist in the presence of antibiotics (bacteria change over time and no longer respond to meds)

Question 3

what are some reasons for the rise of antimicrobial resistance

Answer 3

-over-prescription
-don’t take enough antibiotics
-antibiotics in food supply
-no new antibiotics

Question 4

why have there been no new drugs within the past 50 years

Answer 4

drug development cannot keep up with new infections and antibiotic resistance

Question 5

how do bacteria become genetically resistant to antibiotics?

Answer 5

-spread of resistance genes through genetic transfer events (conjugation, transformation, mutation)

Question 6

what are some global threats discussed in this lecture

Answer 6

-MRSA (Methicillin resistant Staphylococcus aureus)
-VRE (Vancomycin Resistant Enterococci)
-Multidrug and extremenly resistant M. tuberculosis (XDR)

Question 7

what does MRA stand for

Answer 7

multidrug-resistant

Question 8

what does XDR stand for

Answer 8

extensively drug resistant

Question 9

what is MRSA

Answer 9

Methicillin resistant Staphylococcus aureus- bacteria responsisble for difficult-to-treat infections in humans

Question 10

what is VRE

Answer 10

Vancomycin Resistant Enterococci - responsible for hard to clear infections, can lead to complications and death

Question 11

what are multidrug and extremely resistant M. tuberculosis strains

Answer 11

a pressing issue in developing countries, the latent/dormant phase results in carrier state. also a co-infection with HIV

Question 12

what do antibiotics secrete

Answer 12

synthesize and secrete molecules that inhibit growth of other bacteria

Question 13

what makes relevant and appropriate target for inhibition

Answer 13

bacterial features that are unique - protein translation, cell wall, outer membrane, DNA replication

Question 14

what are the classes of antibacterial compounds

Answer 14

-methicillins
-protein synthesis inhibitors
-DNA/RNA inhibiting/altering

Question 15

what is a beta-lactam antibiotic

Answer 15

modified antibiotics, they block cell wall biosynthesis by inhibiting the transpeptide linkage to peptidoglycan & results in weakened cell wall … easier for immune system to kill bacteria

Question 16

what do bacteria fight back with

Answer 16

b-lactamases

Question 17

what are b-lactamases

Answer 17

enzymes that are secreted by bacteria to cleave the b-lactam ring compounds

Question 18

what did chemists respond to b-lactamases with

Answer 18

clavulanic acid

Question 19

what is clavulanic acid

Answer 19

A b-lactamase inhibitor compound that is added to antibiotics

Question 20

what are resistance mechanisms that bacteria use

Answer 20

dont let drug in, pump the drug out, inactive drug (b-lactamases chop up b-lactams), or mutate the target

Question 21

what are biofilms

Answer 21

extracellular goo that protects bacteria from antibiotics

Question 22

what are biofilms made up of

Answer 22

polysaccharides, protein, lipids, DNA, or a mix

Question 23

what is a biofilm capsule

Answer 23

a slimy hydrophobic sticky covering to cells

Question 24

what is an efflux pump

Answer 24

an active transporter in cells that moves out unwanted material

Question 25

function of efflux pump

Answer 25

a method to remove toxic compounds from the cell thereby promoting survival

Question 26

what is combination therapy

Answer 26

treat with multiple antimicrobial agents to reduce the occurrence of surviving antibiotic resistant bacterial strains

Question 27

what is phage therapy

Answer 27

the therapeutic use of bacteriophages for the treatment of pathogenic bacterial infections

Question 28

what are microbiomes

Answer 28

combinations of all microbes that naturally live on or inside our bodies

Question 29

examples of microbiomes

Answer 29

bacteria, fungi, viruses, and their genes

Question 30

what is Clostridium dificille

Answer 30

an anaerobe, spore-former that causes severe diarrhea