CHAPTER 7 Flashcards
1
Q
DRUGS
A
chemicals that affect physiology in any manner
2
Q
CHEMOTHERAPEUTIC AGENTS
A
drugs that act against diseases
3
Q
ANTIMICROBIAL DRUGS
A
drugs that treat infections (antibiotics, synthetic chemicals, semisynthetic)
4
Q
ANTIBIOTICS
A
substances produced by living organisms that can inhibit or destroy other microbes
5
Q
SYNTHETIC CHEMICALS
A
antimicrobials that are completely synthesized in a lab
6
Q
SEMISYNTHETICS
A
chemically altered antibiotics that are more effective, longer lasting, or easier to administer than naturally occurring ones
7
Q
BETA LACTAMS
A
inhibition of cell wall synthesis, prevent bacteria from increasing amount of peptidoglycan, have no effect on existing peptidoglycan layer, effective only for growing cells
8
Q
PENICILINS
A
a molecule that inhibits the growth of staphylococcus aureus bacteria discovered in 1928 by Alexander Fleming
9
Q
CEPHALOSPORINS
A
beta-lactam antimicrobials used to manage a wide range of infections from gram-positive and gram-negative bacteria
10
Q
CARBAPENEMS
A
a class of very effective antibiotic agents commonly used for the treatment of bacterial infections
11
Q
VANCOMYCIN
A
interfere with bridges that link NAG subunits in many Gram-Positive bacteria
12
Q
BACITRACIN
A
blocks transport of NAG and NAM from cytoplasm
13
Q
ISONIAZID
A
disrupt mycolic acid formation in mycobacterial species
14
Q
ETHAMBUTOL
A
disrupt mycolic acid information in mycobacterial species (treats tuberculosis)
15
Q
PROTEIN SYNTHESIS INHIBITORS
A
two general mechanisms. Interference with bacterial ribosomes and with charging of transfer RNA molecules
16
Q
AMINOGLYCOSIDES
A
a medicinal and bacteriologic category of traditional gram-negative antibacterial medications that inhibit protein synthesis and contain a portion of the molecule an amino-modified glycoside (sugar)
17
Q
TETRACYCLINE
A
antibiotic that treats acne
18
Q
CHLORAMPHENICOL
A
antibiotic that is used to treat serious infections in different parts of the body, sometimes given with other antibiotics
19
Q
LICOSAMIDES
A
anticonvulsant that treats partial seizures
20
Q
STREPTOGRMINS
A
a class of antibiotics that work by inhibiting the synthesis of protein in bacteria
21
Q
MACROLIDES
A
a class of drugs used to manage and treat various bacterial infections. (Azithromycin, clarithromycin, and
erythromycin are commonly used to treat infections like pneumonia, sinusitis, pharyngitis, and tonsillitis.)
22
Q
ANTISENSE NUCLEIC ACIDS
A
single-stranded oligonucleotides that have been specifically chemically modified which can bind to RNA expressed by target genes through base complementary pairing & affect protein synthesis at the level of
posttranscriptional processing or protein translation
23
Q
MUPIROCIN
A
an antibiotic that treats skin infections
24
Q
POLYMYXIN
A
disrupts the LPS and cytosolic membranes of gram-negative bacteria
25
NYSTATIN AND AMPHOTERICIN B
attach to ergosterol in fungal membranes
26
AZOLES AND ALLYLAMINES
inhibit ergosterol synthesis
27
METABOLIC ANTAGONIST
a type of “cytotoxic” type of drug that kills cells by mimicking the molecules that a cell needs to grow (sulfonamides and trimethoprim)
28
SULFONAMIDES
a class of synthetic antimicrobial drugs that are pharmacologically used as broad spectrum for the treatment of human and animal bacterial infections
29
TRIMETHOPRIM
an antibiotic and folate synthesis inhibitor that can treat infections including urinary tract and ear infections
30
ATOVAQUONE
an antifungal and anti-parasite that is used to treat and prevent Pneumocystis carinii pneumonia (PCP)
31
BLOCKERS OF UNCOATING
antiviral drugs that block viral un-coating and attachment
32
PROTEASE INHIBITORS
medications that help slow the progression of HIV, by blocking the enzyme “protease” which HIV cells need to develop and mature. (This blocks the virus from making copies of itself)
33
HEAVY METALS
enzymes that are denatured by drugs
34
NUCLEIC ACID SYNTHESIS INHIBITORS
drugs often affect both eukaryotic and prokaryotic cells, not normally used to treat infections, used in research and perhaps slow cancer cell replication
35
INHIBITORS OF DNA REPLICATION
gyrase inhibitors, nucleotide or nucleoside analogs, reverse transcriptase inhibitor
36
GYRASE INHIBITORS
quinolones (synthetic drugs) that inhibit DNA replication process
37
QUINOLONES AND FLUOROQUINOLONES
act against prokaryotic DNA gyrase
38
NUCLEOTIDE OR NUCLEOSIDE ANALOGS
interfere with function of nucleic acids, distort shapes of nucleic acid molecules and prevent further replication, transcription, or translation, most often used against viruses, effective against viruses
39
REVERSE TRANSCRIPTASE INHIBITORS
act against an enzyme HIV uses in its replication cycle, does not harm people because humans lack reverse transcriptase
40
INHIBITORS OF TRANSCRIPTION
nucleotide and nucleoside analogs, RNA polymerase inhibitors
41
ATTACHEMENT ANTAGONISTS
block viral attachment or receptor proteins
42
THERAPEUTIC INDEX
a quantitative measurement of the relative safety of a drug. (a comparison of the amount of a therapeutic agent that causes the therapeutic effect to the amount that causes toxicity)
43
SPECTRUM OF ACTION
the range of bacterial types against which the antibiotic is effective, where these types often are measured in terms of inherent sensitivities
44
NARROW SPECTRUM
effective against few organisms
45
BROAD SPECTRUM
effective against many organisms
46
DIFFUSION SUSCEPTIBILITY TESTS
determines which antibiotics are effective against specific species of bacteria
47
MINIMUM INHIBITORY CONCENTRATION TEST (MIC)
test that determines the lowest concentration of an antimicrobial drug that can inhibit the growth of an organism or MIC value
48
MINIMUM BACTERIAL CONCENTRATION TEST (MBC)
test that determine the lowest concentration of an antimicrobial drug that can kill an organism or MBC value
49
TOPICAL
application of drug for external infections
50
ORAL ROUTE
requires no needles and is self-administered
51
INTRAVENOUS
administration delivers drug directly to bloodstream
52
MULTIPLE DRUG RESISTANCE
pathogen can acquire resistance to more than one drug, common when R plasmids exchanged, develop in hospitals and nursing homes (constant use of drugs eliminates sensitive cells), multiple-drug-resistant pathogens are resistant to at least three antimicrobial agents
53
This chapter focuses on which of the 3 fundamental types of antimicrobial agents?
Physical agents, chemical agents, and chemotherapeutic agents
54
Any chemical substance that can affect the physiology of an organism is called a?
Drugs
55
Drugs that are used to treat diseases are called?
Chemotherapeutic agents
56
Drugs that are used to treat infections are called?
Antimicrobial drugs
57
Antimicrobial drugs that are produced naturally by microorganisms, primarily bacteria and molds are called?
Antibiotics
58
Antimicrobial drugs that are completely synthesized in a lab are called?
Synthetic chemicals
59
Antimicrobial drugs that are chemically altered antibiotics that are more effective, longer lasting, or easier to administer that naturally occurring ones are called?
Semisynthetic
60
Do chemotherapeutic agents exhibit high or low selective toxicity?
Low
61
Antibiotics are antimicrobial drugs most associated with the treatment of what type of pathogens?
Microbes
62
Which type of antimicrobial drugs are there more of and why?
Antibacterial. Because they target cell walls, which humans do not have
63
What are the six main mechanisms of action for antimicrobial drugs?
1. Inhibition of cell wall synthesis
2. inhibition of protein synthesis
3. disruption of cytoplasmic membrane
4. inhibition of general metabolic pathways
5. inhibition of DNA and RNA synthesis
6. inhibition of attachment of entry into host cell
64
Are bacterial cell wall inhibitors only effective against actively dividing cells or can they destroy non-dividing cells too?
Actively dividing cells
65
Are cell wall inhibitors typically cidal or static?
In a clinical application, it does not matter if it is cidal or static, in a lab setting it is cidal in a low setting and static in a high setting (but it does not matter if they are cidal or static as long as they are working)
66
What are the five classes of cell wall inhibitors and the basic mechanisms by which each works?
1. Beta-lactams: blocks transpeptidase activity which prevents cell wall synthesis. Penicillin, cephalosporins, carbopenams
2. Vancomycin: binds NAG in peptidoglycan and blocks transpeptidase from synthesizing new peptidoglycan
3. Bacitracin: prevents NAG & NAM from being transported from the cytosol making the cell wall incomplete.
4. Isoniazid: disrupt mycolic acid formation in mycobacterial species. Acid fast bacteria only, shut down the synthesis of mycolic acid (leprosy and tuberculosis)
5. Ethambutol: disrupts mycolic acid formation in mycobacterial species. Acid fast bacteria only shut down the synthesis of mycolic acid. (Leprosy tuberculosis)
67
What does the structure of a beta lactam ring look like?
A CARBON ring with 3 carbons, 1 Nitrogen.
68
What are the four major advantages that synthetic cell wall?
1. more stable in acidic environments
2. more readily absorbed
3. less susceptible to deactivation
4. more active against more types of bacteria
69
Are there cell wall inhibitors that are effective against fungi? If so, give an example.
ECHINOCANDINS; block the enzyme needed to make glucan polymer cell walls in fungi
70
What are the two main targets of protein synthesis inhibitors?
Interference with bacterial ribosomes and interference with charging of transfer RNA molecules
71
What is the limitation in selective toxicity for this group of antimicrobials?
We as humans, in our mitochondria have bacteria like ribosomes
72
What are the 7 types of antibiotics from this group that interfere with prokaryotic ribosomes?
30s inhibitors 1. aminoglycosides (streptomycin & gentamycin: bind & disrupt 30s shape) 2. tetracycline (blocks tRNA docking site)
50s inhibitors 3. chloramphenicol (blocks peptidyl transferase) 4. licosamides 5. streptogramins 6. macrolides (4-6 block translocation of ribosome)
7. antisense nucleic acids (single stranded RNA or DNA that is complementary to bacterial mRNA
73
the antibiotic group that block translation by binding to either the small or large ribosomal subunit?
AMINOGLYCOSIDES
74
Which of the antibiotic groups functions by blocking the activity of peptidyl transferase?
CHLORAMPHENICOL
75
Which of the antibiotic group/groups functions by binding to mRNA forming a double stranded molecule of RNA that prevents the initiation complex of translation from forming?
LICOSAMIDS, STREPTOGRAMIN, MACROLIDES
76
What is the example of protein synthesis inhibitors that block the charging of tRNA molecules?
MUPIROCIN
77
Cell membrane disruptors target which types of pathogens?
antifungal & antiprotozoal
78
Antifungal and antiprotozoal cell membrane disruptors target what molecule in their membranes?
ERGOSTEROL
79
What are the 2 mechanisms by which these types of antimicrobials affect this molecule?
Directly destroy or inhibit the synthesis of ergosterol
80
What is the limitation to selective toxicity when using antifungals/antiprotozoals cell membrane disruptors that target molecule form the previous question?
Because there isn't a lot
81
What is the example of an antibacterial cell membrane disruptor we talked about in class?
Polymyxin component of Neosporin (topical)
82
Which type of antifungal/antiprotozoal membrane disruptors attach to ergosterol in their membranes and create pores where ergosterol is located?
Nystatin; increases permeability & kills cells
Amphotericin B; antifungal affects egoistical
83
Which type of antifungal/antiprotozoal membrane disruptors inhibit ergosterol synthesis?
Azoles, allylamines
84
Metabolic inhibitors take advantage of differences in what between the host and pathogens?
Enzymes that carry out different metabolic pathways
85
Antibacterial
metabolic antagonists (sulfonamides and trimethoprim)
86
Antifungal and antiparasitic
drugs that interfere with electron transport in protozoa and fungi (atovaquone) agents that disrupt tubulin polymerization and glucose uptake by many protozoa and parasitic worms
87
Antiviral
blockers of uncoating, protease inhibitors
88
General antimicrobial
drugs that denature enzymes (heavy metals) low selective toxicity (denature our proteins as well, reason why we don’t us them)
89
Typically include drugs that target what two processes in pathogens?
Inhibitors of DNA replication (DNA polymerase), inhibitors of transcription (RNA polymerase) to similar
90
What is the limitation to selective toxicity for these types of antimicrobials?
Cause of many adverse reactions poorly understood drugs maybe toxic to kidney, liver or nerves. Consideration needed when prescribing to a pregnant woman
91
What is one target in the bacterial DNA replication process that allows for high selective toxicity and why? What class of antibiotics use this target?
Nucleotide analogs, it mimics DNA nucleotides. Antiviral
92
What are the 3 types of DNA replication inhibitors and types of pathogens effective against?
QUINOLONES & FLUOROQUINOLONES; act against prokaryotic DNA gyrase
NUCLEOTIDE OR NUCLEOSIDE ANALOGS; interfere with function of nucleic acids, distort shapes of nucleic acids molecules, and prevent further replication, transcription, or translation, most often used against viruses, effective against rapidly dividing cancer cells
93
Why do gyrase inhibitors and reverse transcriptase inhibitors have a high level of selective toxicity?
We as humans lack the reverse transcriptase enzyme so it does not affect us. Gyrase is not found in humans, and it only inhibits topoisomerase
94
What are nucleotide and nucleoside analogs especially effective against viral infections?
They can find viruses that are incorporated into DNA molecules and stop them from replicating
95
What are the 2 types of transcription inhibitors and the type of pathogens they are effective against?
ACTINOMYCIN: low selective toxicity, not normally used in humans, but is an antibiotic
NUCLEOTIDE ANALOGS: mimics RNA nucleotides
RITAMPIN: inhibits bacterial RNA polymerase through transcription
96
Any molecule that can block the attachment of viruses to human cells are called?
Antagonist
97
Just be aware that there are antiviral drugs that block viral attachment and entry and drugs that prevent viral un-coating, which are all required steps for viral pathogenesis
98
Possible bonus question: know at least one of the 7 mechanisms of microbial resistance
1. Produce enzyme that destroys or deactivates drugs
2. Alter their own metabolic chemistry
