L17- antibacterial drugs

Question 1

what is meant by non specific infections

Answer 1

caused by different organisms which produces same symptoms

Question 2

how is the bacteria categorised

Answer 2

• they are either rods or cocci (sphere) shaped

- also by gram staining

Question 3

what does gram + tell you

Answer 3

the outer wall of the bacteria takes up the purple gram staining

Question 4

what deos gram - tell you

Answer 4

the outer wall of the bacteria doesnt takes up the purple gram staining

Question 5

what is antibacterial chemotherapy

Answer 5

chemicals produced by MOS to kill or prevents growht of other MOs

Question 6

difference between static and cidal drugs

Answer 6

static- delays the growth of bacteria

cidal - kills the bacteria off so they cant proliferate

Question 7

what makes these drugs so effecient killing MOS

Answer 7

• has selective toxicity so kills off bacterial cells w/o harming the host
• does this by identifying the exploitable difference between the target pathogen and the host organism

Question 8

what are the expoliatble difference between target MO and host organism

Answer 8

• bacteria has cell wall only
• has plasma membrane but doesnt have sterols
• DNA in singular chromosome
• protein synthesis is specific to bacteria itself
• energy metabolism is different as well because it doesnt have mitochodria

Question 9

what are the potential targets of reactions in the bacteria

Answer 9

-class 2

Question 10

eg of class 2 and drugs used to target class2 reactions

Answer 10

folate metabolism -produces folate for DNA synthesis

• bacteria can make it own while animal cells cant
• sulphonamides - inhibit DNA synthesis by competeting with PABA precursor for DNA

Question 11

cons of using sulphonamides to inhibit bacteria’s growth

Answer 11

• can be anatagonised by excess PABA
• pus and pyrimdine bases can be broken down to components to make DNA so there’s no need for foliac acid
• resistance towards the drug

Question 12

why is it better to target class 3 reactions than class 2

Answer 12

the bacteria or MO will make macromolecules during class3 reactions
-using drugs to inhibit this will prevent synthesis of macromolecules so the MO cant use them anymore

Question 13

what can Antibiotics do and eg of them

Answer 13

• prevents peptidoglycan synthesis

- penicillins

Question 14

properties of bacteria that prevents antibiotic like penicillin from being taken up

Answer 14

• reduced permeability of the membrane

- modified binding sites so the penicillin cant bind

Question 15

drugs to increase permeability bacterial memebrane

Answer 15

• polymixin B - for gram - bacteria

- gramicidin - effective gram + bacteria

Question 16

antibiotics inhibiting protein synthesis

Answer 16

tetracyclins compete with tRNA so the AA cant bind to the polypeptide chain
-proteins not made

streptomycin - interfere with anti codon recognition so the proteins is mis read

Question 17

antibiotics inhibting RNA nad DNA syntehsis

Answer 17

• rifampicin - inhibiting DNA and RNA polymerase

- proflavin - altering base pairing

Question 18

antibiotics inhibting energy metabolism

Answer 18

-metronidazole - broken into cytotoxic products so it destroys the bacteria

Question 19

factors affecting succes of chemo

Answer 19

-drug resistance like MRSA causing resistance bacteria

Question 20

what part of bacteria carries the resistance gene

Answer 20

in the plasmid like producing enzymes to alter antibiotics or degrade them

Question 21

ways of transferring genes from one to another bacteria

Answer 21

• conjugation
• transduction
• transformation

Question 22

ways to avoid antibiotics resistance

Answer 22

• only use them when we need them
• targeted antibiotics use
• optimal doages
• use vaccines and hygiene

Question 23

factors to consider when using drugs or antibiotics

Answer 23

-site of infection
-other drug interactions
-pregnancy
-immune system
-previous drug use
- side effects
hypersensitivity reactions