Required for growth on alkanes. Probably involved in the uptake of micelle-solubilized alkanes. Interacts with the inner membrane protein AupB. Expression increases during biofilm formation on n-hexadecane. Forms an operon with aupB. Mutants show a lower rate of biofilm formation on solid paraffin and on the liquid alkane n-hexadecane, while growth on nonalkane substrates was not affected. Planktonic growth on water-soluble substrates is not affected. Mutants are impaired in the assimilation of n-hexadecane solubilized in surfactant micelles. Belongs to the OmpP1/FadL family.