From Clinical and Environmental Origins Have Distinct Biofilm Composition.

Biofilm formation has been shown to be critical to the success of uropathogens. Although is a common cause of urinary tract infections, its biofilm production capacity, composition, genetic basis, and origin are poorly understood. We investigated biofilm formation in a large and diverse collection of ( = 422). Biofilm matrix composition was assessed in representative strains ( = 63) belonging to two main lineages (G and S) recovered from human infection, colonization, and food-related environment using biofilm detachment approach. To identify factors that could be associated with biofilm formation and structure variation, we used a pangenome-wide association study approach. Almost all the isolates (91%; = 384/422) produced biofilm. Among the 63 representative strains, we identified eight biofilm matrix phenotypes, but the most common were composed of protein or protein-extracellular DNA (eDNA)-polysaccharides (38%, 24/63 each). Biofilms containing protein-eDNA-polysaccharides were linked to lineage G and environmental isolates, whereas protein-based biofilms were produced by lineage S and infection isolates ( < 0.05). Putative biofilm-associated genes, namely, , , , , , , , , , , , and genes, were found with different frequencies (3-100%), but there was no correlation between their presence and biofilm production or matrix types. Notably, was ubiquitous in the collection, while was lineage G-associated, and only four strains carried a complete gene cluster () except one that was without . We provided evidence, using a comparative genomic approach, that the complete cluster was acquired multiple times by and originated from other coagulase-negative staphylococci. Overall, the composition of biofilms was distinct in environmental and clinical isolates, suggesting that modulation of biofilm structure could be a key step in the pathogenicity of these bacteria. Moreover, biofilm production in is -independent, and the complete was acquired from other staphylococci.