Journal of Microbiology & Biology Education
By Stevens, A. M., Smith, A. C., Marbach-Ad, G., Balcom, S. A., Buchner, J., Daniel, S. L., … & Yarwood, S. A.
“Using a Concept Inventory to Reveal Student Thinking Associated with Common Misconceptions about Antibiotic Resistance”
Publisher:
18/1
Pp. 1-18
2017
Using a Concept Inventory to Reveal Student Thinking Associated with Common Misconceptions about Antibiotic Resistance
Type: Empirical
Data collection method: Test
Number of subjects, range: Large — 31 or more
Grade and age of subjects: Adult — over 18 years

Antibiotic function and targets

  • All antibiotics are species-specific.
  • Antibiotics target a specific type of bacteria not a common process (target).
  • Bacteria respond to the antibiotics that are suited to them.
  • Peptidoglycan is the target for all antibiotics.

Gram-positive/Gram-negative difference

a) Related to protein synthesis

  • Protein synthesis mechanism is different in G+ and G-.
  • Protein synthesis is not the same in Gram-positive and Gram-negative sp.; bacterial structure (Gram stain morphology) is related to protein synthesis.

b) Related to overall physiology

  • Gram-negative are more resistant than Gram-positive.
  • Physiology is different in G+ and G−.
  • Gram-positive and Gram-negative have different compositions therefore protein synthesis in the two types of bacteria are different therefore they must have different susceptibility to all antibiotics; Gram-positive and Gram-negative have different compositions therefore protein synthesis in the two types of bacteria are different.
  • Phylogenetic differences between Gram-positive and Gram-negative.
c) Related to cell structure
  • Wall thickness or structure affects entry of antibiotic.
  • Gram-positive cell wall is thicker therefore the microbe is more resistant to all antibiotics.
  • Antibiotics must penetrate cell wall differences in order to impact protein synthesis.

d) Terminology (word association with everyday life or other scientific concepts, and over-generalization)

  • Cell wall is the only difference between Gram-positive and Gram-negative; no other difference among these sets of bacteria.
  • Membrane is the (only) distinction between Gram-positive and Gram-negative (and thus antibiotics affecting protein synthesis are equally effective).
  • Membrane difference between Gram-negative and Gram-positive dictates all antibiotic resistance.
  • Resistance is a coat (skin) protecting the bacterium.
  • Protein synthesis is the same in all bacteria but because of the cell wall the antibiotic can’t get in.