Pseudoenzymes are proteins that are evolutionary related to enzymes but lack relevant catalytic activity. Despite this, many pseudoenzymes are remarkably well conserved and have evolved essential catalytic-independent functions. They are found in almost all enzyme families and are distributed across the whole tree of life. The most abundant pseudoenzyme groups are pseudokinases, pseudophosphatases and pseudoproteases. (Adapted from
PMID:31733177 and
PMID:31618524.)