Nepenthesin

In the late 19th century, Sydney Howard Vines showed that the pitcher fluid from Nepenthes could digest protein in acidic conditions. He suggested the plants were making a digestive enzyme, for which he proposed the name "nepenthin". In the late 1960s, Josef Weigl's group in Germany and Shizuko Amagase's group in Japan each used chromatography to purify the proteolytic activity from several Nepenthes species, finding it to be most active at pH 2–3. Amagase and Shigeru Nakayama proposed the name "Nepenthesin" for the responsible protease(s). In 1998, Kenji Takahashi's group purified protein from 30 liters of Nepenthesia distillatoria fluid, finding activity similar to that previously described, and reporting part of the nepenthesin amino acid sequence. ==References==