Question

Which of the following statements regarding quorum sensing in bacteria is FALSE? (a) Quorum sensing is primarily used to control the population density of a bacterium. (b) Quorum sensing partly relies on a key transcription factor to control gene expression. (c) Quorum sensing may be used to control the expression of virulence factors in pathogens. (d) Quorum sensing is used by many bacterial species to regulate very different processes. (e) Quorum sensing relies on the intracellular concentration of a small amphipathic molecule.

Answer 1

(a) True, Quorum sensing controls the population density by regulation of gene expression. When there is high density , it restricts the expression of certain genes to control the population density

(b) False, The QS relies on the cytplasmic Transcription factors for regulating the gene expression which are often diferent in each condition

(c) True, QS control virulence factor in pathogens such as salmonella and pseudomonas

(d) True, QS is involved different processes such as biofilm production, virulence, motility, bioluminescence, sporulation , etc.

(e) False, the QS depends on the population density which further regulates the concentration of the small amphipathic molecules sucha as N-acyl homoserine lactone (AHL), and the auto inducing peptides (AIP)