Extracellular polymeric substance architecture influences natural genetic transformation of acinetobacter baylyi in biofilms
Merod, Robin T.
Date of Issue2014
School of Civil and Environmental Engineering
Singapore Centre on Environmental Life Sciences Engineering (SCELSE)
Genetic exchange by natural transformation is an important mechanism of horizontal gene transfer in biofilms. Thirty-two biofilm metrics were quantified in a heavily encapsulated Acinetobacter baylyi strain and a miniencapsulated mutant strain, accounting for cellular architecture, extracellular polymeric substances (EPS) architecture, and their combined biofilm architecture. In general, transformation location, abundance, and frequency were more closely correlated to EPS architecture than to cellular or combined architecture. Transformation frequency and transformant location had the greatest correlation with the EPS metric surface area-to-biovolume ratio. Transformation frequency peaked when EPS surface area-to-biovolume ratio was greater than 3 μm2/μm3 and less than 5 μm2/μm3. Transformant location shifted toward the biofilm-bulk fluid interface as the EPS surface area-to-biovolume ratio increased. Transformant biovolume was most closely correlated with EPS biovolume and peaked when transformation occurred in close proximity to the substratum. This study demonstrates that biofilm architecture influences A. baylyi transformation frequency and transformant location and abundance. The major role of EPS may be to facilitate the binding and stabilization of plasmid DNA for cellular uptake.
Applied and environmental microbiology
© 2014 American Society for Microbiology. This paper was published in Applied and Environmental Microbiology and is made available as an electronic reprint (preprint) with permission of American Society for Microbiology. The paper can be found at the following official DOI: [http://dx.doi.org/10.1128/AEM.01984-14]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.