Folding of outer membrane proteins (OMPs) is usually impeded by anionic surfactants.

Many microorganisms produce anionic biosurfactants such as rhamnolipids (RL).

OmpA can be folded in RL above its cmc though RL reduces OmpA stability.

Folding kinetics in RL are only slightly slower than in neutral surfactants.

RL might be able to help bacteria export functional OMPs in secreted micelles.