Figure 5

The dynamics of enzyme discovery. The solid red line represents the number of enzymatic activities by their year of discovery, which is estimated by using the earliest publication linked to the corresponding EC entries in IntEnz database. If no publication is mentioned, the year of creation of the EC entry is used instead. The dotted green line represents the number of activities associated to a biological sequence for the first time. The year of protein-EC number association is estimated using UniProt’s PubMed cross-references and by selecting only articles with less than ten other cited proteins in order to avoid publications related to the sequencing of large genomic regions. The artefact peak in 1961 is due to large number of created entries during the first EC meeting, where many activities were assigned to an EC number without any tractable publication.