The periplasmic linker protein component of an organic solvent efflux pump. Involved in export of a number of low log POW compounds including hexane (log POW 3.5), toluene (log POW 2.5) and dimethylphthalate (log POW 2.3). The solvent resistance phenotype has been postulated to depend on the operon expression level. Low constitutive expression; the srpABC operon is further induced up to 17-fold by organic solvents (e.g. toluene and aliphatic solvents and alcohols) but not by antibiotics, heavy metals, pH, temperature, high NaCl or 60 mM acetic acid. Belongs to the membrane fusion protein (MFP) (TC 8.A.1) family.