I. Selective Sorption of Bacteria from Seawater. II. Mechanism of the Initial Events in the Sorption of Marine Bacteria to Surfaces
Abstract
A distinct sequence of sorption of different bacterial types has been observed both on glass slides and electron microscope grids immersed in seawater for periods of up to 24 hours. A comparison of the bacterial groups initially attracted to a surface with those subsequently adhering firmly to the surface suggests a selective irreversible sorption of certain groups of marine bacteria. Firm adhesion of bacteria in the short time periods considered does not involve pili or holdfast structures. The ability to produce extracellular polymeric fibrils may be important in such selective sorption. Two phases in the process of sorption of marine bacteria to surfaces have been defined as (a) an instantaneous reversible phase, and (b) a time-dependent irreversible phase. Reversible sorption of the non-motile Achromobacter sp. strain R8 decreases to zero as the electrolyte concentration decreases, or as the thickness of the electrical double-layer increases. The electrolyte concentration at which all bacteria are repelled from the glass surface depends on the valency of the electrolyte. The reversible phase of sorption is interpreted in terms of the balance between the electrical double-layer repulsion energies at different electrolyte concentrations and the van der Waals attractive energies. The rotational motion of the motile Pseudomonas sp. strain R3 at a liquid-glass interface is considered in terms of the concept of reversible sorption.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1970
- Accession Number
- AD0715376
Entities
People
- K. C. Marshall
- R. Mitchell
- Ruby Stout
Organizations
- Harvard University