Sorption between microorganisms and clay minerals as determined by the electrical sensing zone particle analyzer

Abstract

Sorption between microbial cells and clay minerals was determined by measuring changes in particle size distribution with an electronic particle counter. Sorption increased as the valency of the cations present on the clay and in the suspending electrolyte increased. Neither the size, motility, or Gram reaction of bacteria nor the size of the clay appeared to influence sorption. Sorption occurred between bacteria and montmorillonite homoionic to monovalent cations only at pH 2 to 4, but did not occur at any pH with yeast cells, which sorbed only in the presence of trivalent cations. Heat-killed cells of yeast lost their ability to sorb, whereas cells killed with benzalkonium chloride did not. The possible implications of these results in sorption of microorganisms in natural habitats are discussed.

Adsorption of the Rhizosphere Bacterium Azospirillum brasilense Cd to Soil, Sand and Peat Particles

“…Bacteria and soil particles (clays and organic matter) possess a similar net negative surface charge (Marshall, 1967), which prevents direct contact and raises the question of how bacteria adsorb to these particles (Marshall, 1975). When soil-origin bacteria are reapplied to soil, the majority adsorb to soil particles but few adsorb to sand particles (Daniels, 1980;Marshall, 1971;Peele, 1936;Rubentschik et al, 1936); both dead and living cells adsorb in a similar fashion (Santoro & Stotzky, 1968). The number of adsorbed symbiotic rhizosphere bacteria (Rhizobium sp.)…”

“…The net electrical charge of the clay surfaces, as well as the surfaces of bacteria are negative (Santoro & Stotzky, 1968). However, clay particles can possess positively charged areas to which bacteria will adsorb (Marshall, 1968;Peele, 1936).…”

Processes in Pathogenic Biocolloidal Contaminants Transport in Saturated and Unsaturated Porous Media: A Review

“…The electrostatic charges on microbial surfaces are caused by dissociation of various inorganic groups like carboxyl and amino groups, located on the outer surface and situated in deeper layers of the cell wall (Santoro and Stotzky 1968). Many microbial cells produce surface appendages (e.g.…”

DIVISION OF ENVIRONMENTAL SCIENCES: CLAY MINERALS AND MICROBIAL ECOLOGY*,†

“…23 In addition to selective sorption between clays and microbes, the differential adsorption, and perhaps inactivation, by clays of microbial substrates and metabolites would influence the relative growth of specific microbial groups in a heterogeneous population. Preliminary studies26 indicated that adsorption of amphoteric compounds occurs essentially only below their IP, and, even then, they a r e readily desorbed.…”