Frog foam-derived recombinant protein as a natural bio surfactant

초록

The tungara frog(Engystomops pustulous) whips its legs to produce the form of an egg case as the meringue is made. The foam float on the water for 2-4weeks until the egg becomes a tadpole and protects eggs from dehydration and infection. In the foam, six main types of proteins were found, and Rasputin 2(RSN2) protein is known as the surfactant protein having hydrophobic and hydrophilic parts. It lowers the surface tension of the water by the protein binding air and water through each characteristic. In nature, many natural surfactants have been reported, such as the natural pulmonary surfactant, which alleviates surface tension in the lung. It prevents the shrinkage phenomenon of the aveolus from regulating surface tension between the inside and outside of the alveolus. Another natural surfactant protein is the latherin of the horse. Latherin exists in sweat and saliva and reduces the surface tension of the skin. The horse can regulate temperature because the biosurfactant protin within oily skin facilitate sweat for evaporation. In this study, the recombinant protein that constructs RSN2 was biosynthesized in the Escherichia coli expression system. We prove the surfactant characteristic of RSN2 such as foaming, emulsion, lower surface tension properties, and the ability to form a micelle. The protein-based micelle would increase the speed of drug-loading, biodegradable properties, and simple characterization nanocarrier. These micelles can use in environmental purification or food technology, as well as in bio-related fields, such as biosensors, drug delivery, or quasi-drug applications.