Polysaccharides and proteins added to flowing drinking water at microgram-per-liter levels promote the formation of biofilms predominated by bacteroidetes and proteobacteria.

Biopolymers are important substrates for heterotrophic bacteria in (ultra)oligotrophic freshwater environments, but information about their utilization at microgram-per-liter levels by attached freshwater bacteria is lacking. This study aimed at characterizing biopolymer utilization in drinking-water-related biofilms by exposing such biofilms to added carbohydrates or proteins at 10 μg C liter(-1) in flowing tap water for up to 3 months. Individually added amylopectin was not utilized by the biofilms, whereas laminarin, gelatin, and caseinate were.

Flavobacterium johnsoniae as a model organism for characterizing biopolymer utilization in oligotrophic freshwater environments.

Biopolymers are important substrates for heterotrophic bacteria in oligotrophic freshwater environments, but information on bacterial growth kinetics with biopolymers is scarce. The objective of this study was to characterize bacterial biopolymer utilization in these environments by assessing the growth kinetics of Flavobacterium johnsoniae strain A3, which is specialized in utilizing biopolymers at μg liter(-1) levels. Growth of strain A3 with amylopectin, xyloglucan, gelatin, maltose, or fructose at 0 to 200 μg C liter(-1) in tap water followed Monod or Teissier kinetics, whereas growth with laminarin followed Teissier kinetics.