Long-term succession of structure and diversity of a biofilm formed in a model drinking water distribution system.
In this study, we examined the long-term development of the overall structural morphology and community composition of a biofilm formed in a model drinking water distribution system with biofilms from 1 day to 3 years old. Visualization and subsequent quantification showed how the biofilm developed from an initial attachment of single cells through the formation of independent microcolonies reaching 30 micro m in thickness to a final looser structure with an average thickness of 14.1 micro m and covering 76% of the surface. An analysis of the community composition by use of terminal restriction fragment length polymorphisms showed a correlation between the population profile and the age of the sample, separating the samples into young (1 to 94 days) and old (571 to 1,093 days) biofilms, whereas a limited spatial variation in the biofilm was observed. A more detailed analysis with cloning and sequencing of 16S rRNA fragments illustrated how a wide variety of cells recruited from the bulk water initially attached and resulted in a species richness comparable to that in the water phase. This step was followed by the growth of a bacterium which was related to Nitrospira, which constituted 78% of the community by day 256, and which resulted in a reduction in the overall richness. After 500 days, the biofilm entered a stable population state, which was characterized by a greater richness of bacteria, including Nitrospira, Planctomyces, Acidobacterium, and Pseudomonas. The combination of different techniques illustrated the successional formation of a biofilm during a 3-year period in this model drinking water distribution system.
Martiny
Adam C
AC
BioCentrum-DTU, Technical University of Denmark, DK-2800 Lyngby, Denmark.
Jørgensen
Thomas M
TM
Albrechtsen
Hans-Jørgen
HJ
Arvin
Erik
E
Molin
Søren
S
D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000254:growth & development*; D018441:Biofilms / Q000254:growth & development*; D003001:Cloning, Molecular; D004275:DNA, Ribosomal / Q000032:analysis; D017753:Ecosystem; D005618:Fresh Water / Q000382:microbiology*; D014644:Genetic Variation; D018613:Microscopy, Confocal; D008954:Models, Biological; D008969:Molecular Sequence Data; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D014881:Water Supply
D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S