11. Controlling Microbial Growth

Which of the following chemical agents is a gas? 

You and your classmates are trying to determine how a disinfectant might kill cells. You observe that when you spill the disinfectant in a tube of reduced litmus milk, the litmus turns blue again. You suggest to your classmates that

a. the disinfectant might inhibit cell wall synthesis.

b. the disinfectant might oxidize molecules.

c. the disinfectant might inhibit protein synthesis.

d. the disinfectant might denature proteins.

e. the disinfectant might damage DNA.

DRAW IT Show where the following antibiotics work: ciprofloxacin, tetracycline, streptomycin, vancomycin, polymyxin B, sulfanilamide, rifampin, erythromycin.

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Why does a cell die from the following antimicrobial actions?

a. Colistimethate binds to phospholipids.

b. Kanamycin binds to 70S ribosomes.

How does each of the following inhibit translation?

a. chloramphenicol

b. erythromycin

c. tetracycline

d. streptomycin

e. oxazolidinone

f. streptogramin

NAME IT This microorganism is not susceptible to antibiotics or neuromuscular blocks, but is susceptible to protease inhibitors.

Which of the following pairs is mismatched?

a. antihelminthic—inhibition of oxidative phosphorylation

b. antihelminthic—inhibition of cell wall synthesis

c. antifungal—injury to plasma membrane

d. antifungal—inhibition of mitosis

e. antiviral—inhibition of DNA synthesis

Match the antimicrobial drug class to its action. You may assign more than one drug class to a given action and some actions may not be applicable.