Question

For a physician, treating a biofilm infection in a patient poses a significant challenge compared to treating an infection with planktonic (free-floating) bacteria. This is due to the fact that the biofilm likely contains several different species of bacteria living in a thick, extracellular matrix that

a. cannot be penetrated and therefore treated by routine antibiotic therapy
b. planktonic(free-floating) bacteria secrete quorum-sensing proteins that break down the antibiotic
c. despite being a thick layer, the pH remains constant throughout the biofilm making the deep layers hard to penetrate
d. planktonic (free-floating) bacteria and biofilm bacteria activate the same genes

Answer 1

Treating biofilm infections is challenging because the extracellular matrix of the biofilm provides a protective barrier and facilitates resistance to antibiotics, leading to treatments that are less effective than those for planktonic bacteria.

Step-by-step explanation:

The challenge in treating biofilm infections compared to infections with planktonic (free-floating) bacteria arises because the biofilm is composed of different bacterial species within a robust extracellular matrix. This matrix acts as a formidable barrier that can prevent routine antibiotics from penetrating and effectively treating the infection. The extracellular polymeric substances (EPS) act not only as a physical shield but also lead to phenotypic changes in the bacteria, such as the increased production of efflux pumps, which enhance their resistance to antibiotics.

Moreover, biofilms support an environment favorable for the transfer of antibiotic resistance genes among bacteria, compounding the difficulty in treatment. As a result, biofilms can be up to a thousand times more resistant to antibiotics than planktonic bacteria, necessitating alternative treatment strategies that are currently being researched by scientists.