Hydrogel is used in contact lenses and diapers. Some kinds of hydrogel are made of self-assembling peptides. They are amphiphilic peptides and they form nanostructured hydrogel under physiochemical conditions. Recently, they have been considered as a good biological scaffold for cell culturing and drug delivering. They are synthesized chemically such as solid-state synthesis, but it’s not efficient for production in large amounts. So, we need another approach including biosynthesis.