Application of bacterial16S rRNAgene analysis to a comparison of the degree of biofilm formation on the surface of metal coated glasses

The contaminated surfaces of materials are generally covered with a biofilm that consists of microorganisms and extracellular polysaccharides. The Gram stain method, which is used to visualise bacteria, allows biofilms to be semiquantitatively analysed. Although this method can be used to compare the amount of bacteria in a biofilm, we cannot identify kinds of bacteria. In the present study, 16S rRNA gene analysis was performed to measure and determine the bacterial population in biofilms formed on organic nickel coated glass and uncoated glass. The amount of 16S rRNA was markedly higher on organic nickel coated glass than on uncoated glass. 16S rRNA sequencing revealed that the majority of bacteria on uncoated glass and organic nickel coated glass were Proteobacteria, especially Sphingomonadales and Methylophilales; however, a marked difference was observed in the amount of Sphingomonadales on these glasses.