Term
List 8 Gram positive genera |
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Definition
1. Staphylococcus 2. Streptococcus 3. Enterococcus 4. Listeria 5. Cornybacterium 6. Bacillus 7. Clostridium 8. actinomyces |
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Term
List the important acid fast organisms (remember that acid fast are gram+ variants that have myocolic acids attached via arabinogalacitan to peptidoglycan) |
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Definition
1. Mycobacterium a. M. tuberculosis b. M. leprae c. M. avium complex 2. Nocardia 3. Corynebacterium may be partially acid fast |
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Term
What are two examples of mollicutes? (remember that mollicutes are gram+ variants that have lost their cell wall) |
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Definition
1. mycoplasma 2. ureaplasma |
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Term
Whare are 3 important spirochetes? (remember that spirochetes are gram- variants that have a flagella located between the outer membrane and PG layer) |
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Definition
1. borrelia 2. leptospira 3. treponema |
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Term
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Definition
unrelated to gram - have plasma and outer membranes including LPS but no peptidoglycan layer. They have a dimorphic life cycle: elementary bodies (environmentally resistant extracellular form which have CRPs that cross link to provide the cell with rigidity) and reticulate bodies (environmentally sensitive form)
the CRPs in the elementary bodies play the role of PGlayer.
Major pathogenic genera: Chlamydophila Chlamydia |
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Term
What are three examples of Beta lactam antibiotics and what do they generally target? |
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Definition
penicillins, cephalosporins, carbapenems, monobactams
bind and inhibit primarily transpeptidases via their structural analogy to the PG subunit
NEW PG is weak and leads to cell lysis |
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Term
Give 2 examples of glycopeptides and explain generally their MOA |
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Definition
Vancomycin and teicoplanin Large molecules that prevent transpeptidation and interfere with transglycosylation by binding the D-ala-D-ala portion of hte stem peptide and getting in the way. |
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Term
Exaplain the MOA of Bacitracin (polysporin) |
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Definition
popypeptide that prevents dephosphorylation of the Und-P-P molecule, which prevents its recylcing. This leads to a lack of Und-P, which interferes with several processes including PG syntehsis, LPS, capsules, teichoic acid synthesis etc... |
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Term
Explain the MOA of Cycloserine |
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Definition
used to treat mycobacteria Prevents the formation of D-ala-D-ala through the inhibition of both alanine racemase and D-ala-D-ala synthetase,
which puts these two amino acids together in preparation for their attachment to hte peptide tail of the PG monomer. |
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Term
Explain the MOA of fosfomycin |
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Definition
inhibits MurA, which is involved in the production of NAM and NAG |
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Term
What is the MOA for Tunicamycin? |
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Definition
nucleoside analogue with prevents NAM-P to Und-P transfer |
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Term
Which drug specifically targets the production of mycobacterial cell envelope components i.e. mycoloic acids? |
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Definition
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Term
Which drug specifically targets the production of mycobacterial cell envelope components i.e. arabinogalactan? |
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Definition
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Term
What is the MOA of lysoszyme as an innate antibacterial? |
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Definition
it cleaves the bonds between the NAM and NAG sugars and leads to bacterial cell lysis. |
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Term
What are two examples of transglycosylase inhibitors which have large complex structures? |
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Definition
ramoplanin and moenomycin |
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Term
how does the endopeptide lysostaphin work? |
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Definition
cleaves the pentaglycine bridge found between stem peptides in S. aureus, resulting in weakening of the PG and lysis of hte bacterial cell. They have shown some promise in treating infection. |
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Term
2 sporulating species of bacteria |
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Definition
bacillus (aerobe) clostridium (anaerobe) |
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Term
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Definition
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Term
Quinolones (e.g. ciproflaxin) MOA? |
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Definition
target DNA synthesis; bacterial topoisomerases (gyrase and topoisomerase IV) |
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Term
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Definition
inhibit folate synthesis, which is required for DNA synthesis. |
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Term
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Definition
prevents folate reduction |
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Term
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Definition
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Term
Aminoglycosidse and tetracyclines target which ribosomal subunit? |
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Definition
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Term
Chloramphenicol, lincosamides, macrolides, oxazolidinones and streptogramins target which ribosomal subunit? |
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Definition
23s portion of the 50s ribosomal subunit |
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