The Pel polysaccharide is predominantly composed of a dimeric repeat of α-1,4 linked galactosamine and N-acetylgalactosamine

The genetic capacity to synthesize the biofilm matrix exopolysaccharide Pel is widespread among Gram-negative and Gram-positive bacteria. However, its exact chemical structure has been challenging to determine. Using a Pseudomonas aeruginosa strain engineered to overproduce Pel, improvements to the isolation procedure, and selective hydrolysis with the glycoside hydrolase PelA(h), we demonstrate that Pel is a partially de-N-acetylated linear polymer of alpha-1,4-N-acetylgalactosamine comprised predominantly of dimeric repeats of galactosamine and N-acetylgalactosamine.

Automated summary

This study determined the exact chemical structure of the biofilm matrix exopolysaccharide Pel using an improved isolation procedure and selective hydrolysis with the glycoside hydrolase PelA(h).