Viruses help form biofilms

Bacteria frequently grow in communities called biofilms, which are aggregates of cells and polymers. An example of a biofilm is the dental plaque on your teeth. Biofilms are medically important as they can allow bacteria to persist in host tissues and on catheters, and confer increased resistance to antibiotics and dessication. Therefore understanding how biofilms form is crucial for controlling microbial infections. An advance in our understanding of how biofilms form is the observation that filamentous phages help them assemble, and contribute to their fundamental properties. Pseudomonas aeruginosa is an important human pathogen which is a particular problem in patients with cystic fibrosis. The ability of this bacterium to form biofilms in the lung is linked to its ability to cause chronic infections. Pseudomonas aeruginosa biofilms contain large numbers of filamentous Pf bacteriophages (pictured; image credit). These viruses lyse cells and release DNA, which becomes one component of the biofilm matrix. Mixing supernatants of P. aeruginosa cultures with hyaluronan, which is present in airways of cystic fibrosis patients, resulted in the formation of a biofilm – in the absence of bacteria. A major component of P. aeruginosa biofilms was found to be Pf bacteriophages. When purifed Pf bacteriophages were mixed with hyaluronan, biofilms formed. Similar biofilms also formed when the filamentous bacteriophage fd of E. coli was mixed with hyaluronan. Mixtures of Pf...
Source: virology blog - Category: Virology Authors: Tags: Basic virology Information bacteria bacteriophage biofilm birefringence liquid crystal matrix microbe microbiology polymers Pseudomonas aeruginosa viral virus Source Type: blogs