Kallikreins are a subgroup of
serine proteases,
enzymes capable of cleaving peptide bonds in proteins. In humans, plasma kallikrein (
KLKB1) has no known paralogue, while tissue kallikrein-related peptidases (
KLKs) encode a family of fifteen closely related serine proteases. These genes are localised to chromosome
19q13, forming the largest contiguous cluster of proteases within the human genome. Kallikreins are responsible for the coordination of various physiological functions including
blood pressure,
semen liquefaction and
skin desquamation.