Behavior of Rhodococcus opacus during desiccation in the presence of hexadecane vapors.

ALVAREZ H.M.; SILVA R.A.; ZAMIT A.L.; CESARI A.C.; ALVAREZ A.F.; RAMIREZ M.V.

Congreso; XXXIX Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB).; 2003

Desiccation plays a determinative role in the survival of microorganisms in the environment, principally in desert regions such as in the semiarid Patagonia. The aim of this study was to investigate the behavior of the soil isolate Rhodococcus opacus PD630 subjected to desiccation during exposure of hexadecane vapors. Similar situation is found in natural arid environments contaminated with hydrocarbons during non-rainy periods. Exposure of desiccated cells to hexadecane vapors produced the following effects: 1) hexadecane likely exerted a toxic action at the cellular envelope level resulting in cell deformation and a decrease of survival; 2) removal of an extracellular polymer accumulated at colony surfaces during desiccation; 3) production of microcolonies principally in the inner sector of colonies; 4) mobilization of storage lipids (triacylglycerols) presumably for producing the energy necessary for the re-adaptation of cellular physiology; 5) turnover of fatty acids and mycolic acids. Results of this study suggested that R. opacus colonies contain cells with different physiological status, some of them being not able to survive under these conditions, whereas others respond actively to the presence of hexadecane vapors during desiccation.