Lon protease family

In molecular biology, the Lon protease family is a family of enzymes that break peptide bonds in proteins resulting in smaller peptides or amino acids.^[1] They are found in archaea, bacteria and eukaryotes. Lon proteases are ATP-dependent serine peptidases belonging to the MEROPS peptidase family S16 (Lon protease family, clan SJ). In the eukaryotes the majority of the Lon proteases are located in the mitochondrial matrix.^[2][3] In yeast, the Lon protease PIM1 is located in the mitochondrial matrix. It is required for mitochondrial function, it is constitutively expressed but is increased after thermal stress, suggesting that PIM1 may play a role in the heat shock response.^[4] Lon proteases have two specific subfamilies: LonA and LonB, differentiated by the number of AAA+ domains found in the protein.^[5][6]

ATP-dependent protease La (LON) domain
crystal structure of n-terminal domain of e.coli lon protease
Identifiers
Symbol	LON
Pfam	PF02190
Pfam clan	CL0178
InterPro	IPR003111
SMART	LON
MEROPS	S16
SCOP2	1zbo / SCOPe / SUPFAM
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

Lon protease (S16) C-terminal proteolytic domain
Identifiers
Symbol	LON
Pfam	PF05362
Pfam clan	CL0329
InterPro	IPR008269
MEROPS	S16
SCOP2	1rr9 / SCOPe / SUPFAM
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

See also

• LONP1