Selective pseudosolubilization capability of Pseudomonas sp. DG17 on n-alkanes and uptake mechanisms analysis

Pseudosolubilized ability of Pseudomonas sp. DG17 on n-alkanes, role of biosurfactants in n-octadecane uptake and trans-membrane transport mechanism of n-octadecane were studied by analyzing amount of pseudosolubilized oil components in water phase, and the fraction of radiolabeled ¹⁴C n-octadecane in the broth and cell pellet. GC-MS results showed that pseudosolubilized oil components were mainly C₁₂ to C₂₈ of n-alkanes. In n-octadecane broth, pseudosolubilized n-octadecane could be accumulated as long as pseudosolubilized rate was faster than mineralization rate of substrate, and the maximum concentration of pseudosolubilized n-octadecane achieved to 45.37 mg·L^?1. All of these results showed that Pseudomonas sp. DG17 mainly utilized alkanes by directly contacting with pseudosolubilized small oil droplets in the water phase. Analysis of ¹⁴C amount in cell pellet revealed that an energy-dependent system mainly controlled the trans-membrane transport of n-octadecane.