CELL-SURFACE PROPERTIES OF THE FOOD-BORNE AND WATER-BORNE PATHOGEN AEROMONAS-HYDROPHILA WHEN STORED IN BUFFERED SALINE SOLUTIONS

Aeromonas hydrophila, a ubiquitous inhabitant of aquatic environments, commonly expresses several cell-surface properties that may contribut e to virulence. Since many aquatic microorganisms in hostile environme nts can withstand starvation conditions for long periods, we examined the effect of storage under nutrient-poor conditions on the expression of cell-surface properties of this pathogen. Phenotypes studied were: (1) cell-surface hydrophobicity and charge, and (2) the ability to bi nd connective-tissue proteins and lactoferrin. Our results suggest tha t the response of A. hydrophila to nutrient-poor conditions is regimen specific. Generally, A. hydrophila cells became more hydrophobic and significantly increased their ability to bind the iron-binding glycopr otein lactoferrin when the bacterium was stored under nutrient-poor co nditions; however, under these conditions, the cells seemed to lose th eir ability to bind connective-tissue proteins.