Cloned (Comment) | Organism |
---|---|
gene lon, recombinant expression of C-terminally His6-tagged wild-type and mutant enzymes in Escherichia coli strain BL21(DE3) | Escherichia coli |
Protein Variants | Comment | Organism |
---|---|---|
additional information | analysis of the propensity of C-His-Lon and mutant enzymes Lon-R164A, Lon-R192A, and Lon-Y294A for autodegradation reveals that Lon-Y294A is most prone to autolysis. Slight autolysis of the intact enzyme and the mutant forms of Lon-R164A and Lon-R192A is observed only in the absence of nucleotides | Escherichia coli |
R164A | site-directed mutagenesis, mutation of a HI(CC) domain residue, helix H3, the mutant shows highly reduced ATPase activity in presence of beta-casein compared to the wild-type | Escherichia coli |
R192A | site-directed mutagenesis, mutation of a HI(CC) domain residue, the mutant shows highly reduced ATPase activity in presence of beta-casein compared to the wild-type | Escherichia coli |
Y294A | site-directed mutagenesis, mutation of a HI(CC) domain residue, the mutant shows highly reduced ATPase activity in presence of beta-casein compared to the wild-type | Escherichia coli |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
ADP | free ADP inhibits all forms of Ec-Lon, while a complex of ADP with magnesium ions (ADP-Mg) activates C-His-Lon and Lon-R164A and inhibits the mutant forms Lon R192A and Lon-Y294A | Escherichia coli |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required, activates | Escherichia coli |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | P0A9M0 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant C-terminally His6-tagged wild-type and mutant enzymes from Escherichia coli strain BL21(DE3) by nickel affinity chromatography and gel filtration | Escherichia coli |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
beta-casein + H2O | - |
Escherichia coli | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
homohexamer | - |
Escherichia coli |
More | enzyme Ec-Lon subunit includes an ATPase component and a proteolytic component (AAA+ module and P-domain, respectively), as well as a noncatalytic region formed by the N-terminal (N) domain and an inserted alpha-helical (HI(CC)) domain. This region is unique for AAA+ proteins. The C-terminal part of the HI(CC) domain has an allosteric effect on the efficiency of the functioning of both ATPase and proteolytic sites of the enzyme, while the coiled-coil (CC) fragment of this domain interacts with the protein substrate. The HI(CC) domain is not essential for the formation of the ATPase center of Ec-Lon protease, but still has an effect on the functional efficiency of this center. Detailed analysis and comparisons of primary and secondary structures of the HI(CC) domain in AAA* proteases, overview | Escherichia coli |
Synonyms | Comment | Organism |
---|---|---|
ATP-dependent protease LonA | - |
Escherichia coli |
Ec-Lon | - |
Escherichia coli |
lonA | - |
Escherichia coli |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
37 | - |
- |
Escherichia coli |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
8.1 | - |
- |
Escherichia coli |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
ATP | dependent on | Escherichia coli |
General Information | Comment | Organism |
---|---|---|
evolution | LonA from Escherichia coli belongs to the superfamily of AAA+ proteins, family S16 of proteases. The presence of an extended variable N-terminal region preceding the AAA+ modules is a characteristic feature of LonA proteases distinguishing them from other AAA+ proteins | Escherichia coli |
additional information | the C-terminal part of the HI(CC) domain has an allosteric effect on the efficiency of the functioning of both ATPase and proteolytic sites of the enzyme, while the coiled-coil (CC) fragment of this domain interacts with the protein substrate. Analysis of the propensity of C-His-Lon and mutant enzymes Lon-R164A, Lon-R192A, and Lon-Y294A for utodegradation reveals that Lon-Y294A is most prone to autolysis. Slight autolysis of the intact enzyme and the mutant forms of Lon-R164A and Lon-R192A is observed only in the absence of nucleotides | Escherichia coli |
physiological function | LonA from Escherichia coli plays a key role in the quality control system of the cell proteome. It destroys abnormal and defective polypeptides, as well as a number of regulatory proteins, according to a processive degradation mechanism | Escherichia coli |