Spatial and temporal deposition of Hyphomonas strain VP-6 capsules involved in biofilm formation

Abstract

Hyphomonas strain VP-6 is a prosthecate bacterium isolated from the Guayamas vent region and is a member of a genus of primary and common colonizers of marine surfaces. It adheres to solid substrata as a first step in biofilm formation. Fine-structure microscopy and the use of specific stains and lectins reveal that it synthesizes two different extracellular polymeric substances (EPS). One is a temporally synthesized, polar holdfast EPS, and the other is a capsular EPS that is present during the complete life cycle and surrounds the entire cell, including the prosthecum. The timing and location of Hyphomonas strain VP-6 EPS elaboration correlate with adhesion to surfaces, suggesting that the EPS serves not only as the biofilm matrix but also as a primary adhesin. The temporality and polarity of VP-6 EPS expression substantially differ from those properties of Hyphomonas strain MHS-3 EPS expression.