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113  structures 8242  species 0  interactions 16802  sequences 116  architectures

Family: Lon_C (PF05362)

Summary: Lon protease (S16) C-terminal proteolytic domain

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This is the Wikipedia entry entitled "Lon protease family". More...

Lon protease family Edit Wikipedia article

ATP-dependent protease La (LON) domain
PDB 2ane EBI.jpg
crystal structure of n-terminal domain of e.coli lon protease
Symbol LON
Pfam PF02190
Pfam clan CL0178
InterPro IPR003111
SCOP 1zbo
Lon protease (S16) C-terminal proteolytic domain
Symbol LON
Pfam PF05362
Pfam clan CL0329
InterPro IPR008269
SCOP 1rr9

In molecular biology, the Lon protease family is a family of proteases. 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.[1][2] 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.[3]

See also


  1. ^ Wang N, Gottesman S, Willingham MC, Gottesman MM, Maurizi MR (December 1993). "A human mitochondrial ATP-dependent protease that is highly homologous to bacterial Lon protease". Proc. Natl. Acad. Sci. U.S.A. 90 (23): 11247–51. doi:10.1073/pnas.90.23.11247. PMC 47959Freely accessible. PMID 8248235. 
  2. ^ Barakat S, Pearce DA, Sherman F, Rapp WD (May 1998). "Maize contains a Lon protease gene that can partially complement a yeast pim1-deletion mutant". Plant Mol. Biol. 37 (1): 141–54. doi:10.1023/A:1005912831051. PMID 9620272. 
  3. ^ Van Dyck L, Pearce DA, Sherman F (January 1994). "PIM1 encodes a mitochondrial ATP-dependent protease that is required for mitochondrial function in the yeast Saccharomyces cerevisiae". J. Biol. Chem. 269 (1): 238–42. PMID 8276800. 

External links

This article incorporates text from the public domain Pfam and InterPro IPR003111

This page is based on a Wikipedia article. The text is available under the Creative Commons Attribution/Share-Alike License.

This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.

Lon protease (S16) C-terminal proteolytic domain Provide feedback

The Lon serine proteases must hydrolyse ATP to degrade protein substrates. In Escherichia coli, these proteases are involved in turnover of intracellular proteins, including abnormal proteins following heat-shock. The active site for protease activity resides in a C-terminal domain. The Lon proteases are classified as family S16 in Merops.

Literature references

  1. Vasilyeva OV, Kolygo KB, Leonova YF, Potapenko NA, Ovchinnikova TV; , FEBS Lett 2002;526:66-70.: Domain structure and ATP-induced conformational changes in Escherichia coli protease Lon revealed by limited proteolysis and autolysis. PUBMED:12208506 EPMC:12208506

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR008269

Lon (also known as endopeptidase La) is a multi-domain ATP- dependent protease found throughout all kingdoms of life. It is involved in protein quality control and several regulatory processes. All Lon proteases contain an ATPase domain belonging to the AAA+ superfamily of molecular machines, and a proteolytic domain with a serine-lysine catalytic dyad in which a lysine assists the catalytic serine in proteolytic cleavage. Lon proteases can be divided into two subfamilies: A type (A-Lons), which have a large multi-lobed N-terminal domain together with the ATPase and protease domains, and B type (B-Lons), which lack an N domain, but have a membrane-anchoring region emerging from the ATPase domain. B-Lons are found in Archaea, in which they are the lone membrane-anchored ATP-dependent protease. The soluble A-Lons are found in all bacteria and in eukaryotic cell organelles, such as mitochondria and peroxisomes, and are needed for recovery from various stress conditions [ PUBMED:14665623 , PUBMED:15456757 , PUBMED:16002085 , PUBMED:20834233 , PUBMED:20222013 , PUBMED:24520911 ]. The Lon proteolytic domain forms peptidase family S16 of clan SJ [ PUBMED:16002085 ].

The structure of the Lon proteolytic domain consists of six alpha helices and ten beta strands [ PUBMED:14665623 , PUBMED:15456757 , PUBMED:16002085 , PUBMED:20834233 , PUBMED:20222013 ].

Gene Ontology

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Domain organisation

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Pfam Clan

This family is a member of clan S5 (CL0329), which has the following description:

This superfamily contains a wide range of families that possess a structure similar to the second domain of ribosomal S5 protein.

The clan contains the following 18 members:

ChlI DNA_gyraseB DNA_mis_repair EFG_IV Fae GalKase_gal_bdg GHMP_kinases_N IGPD Lon_C LpxC Morc6_S5 Ribonuclease_P Ribosomal_S5_C Ribosomal_S9 RNase_PH Topo-VIb_trans UPF0029 Xol-1_N


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Curation and family details

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Seed source: Merops
Previous IDs: none
Type: Domain
Sequence Ontology: SO:0000417
Author: Studholme DJ
Number in seed: 23
Number in full: 16802
Average length of the domain: 179.10 aa
Average identity of full alignment: 33 %
Average coverage of the sequence by the domain: 25.34 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 57096847 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 21.1 21.1
Trusted cut-off 21.1 21.1
Noise cut-off 21.0 21.0
Model length: 205
Family (HMM) version: 15
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Species distribution

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Colour assignments

Archea Archea Eukaryota Eukaryota
Bacteria Bacteria Other sequences Other sequences
Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence


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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Lon_C domain has been found. There are 113 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.

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