Biofilm formation by haloarchaea

Summary A fluorescence‐based live‐cell adhesion assay was used to examine biofilm formation by 20 different haloarchaea, including species of H alobacterium , H aloferax and H alorubrum , as well as novel natural isolates from an Antarctic salt lake. Thirteen of the 20 tested strains significantly adhered ( P ‐value < 0.05) to a plastic surface. Examination of adherent cell layers on glass surfaces by differential interference contrast, fluorescence and confocal microscopy showed two types of biofilm structures. Carpet‐like, multi‐layered biofilms containing micro‐ and macrocolonies (up to 50 μm in height) were formed by strains of H alobacterium salinarum