Question

legionella pneumophila is a gram - negative bacterium that can cause legionnaires disease in immunocompromised individuals. much of its success is attributed to its ability to form a biofilm in the lungs of its host. in this instance, what is the best explanation for the advantage conferred by biofilm formation? the biofilm matrix hampers penetration of antibiotics used to kill l. pneumophila. the biofilm causes an increase in nutrient exchange between host cells and the pathogen. the formation of a biofilm prevents individual bacterial cells from drying out. l. pneumophila recruits other bacterial species, thus causing secondary infections that suppress the immune response. biofilm formation prevents host immune cells from attacking the bacteria present.

Explanation:

Biofilms are communities of bacteria encased in a matrix. In the case of Legionella pneumophila, the biofilm matrix acts as a physical barrier. This barrier makes it difficult for antibiotics to reach and kill the bacteria within, conferring a survival - advantage to the pathogen. While other options may have some merit in general microbial ecology, the main advantage here related to the pathogenicity and treatment - resistance of L. pneumophila is the hindrance of antibiotic penetration.

Answer:

The biofilm matrix hampers penetration of antibiotics used to kill L. pneumophila.