3.4.21.53 5-aminolevulinic acid synthase + H2O - 3.4.21.53 Abf2 + H2O a yeast mitochondrial protein, homologuous to human mitochondrial TFAM protein 3.4.21.53 Abnormal puromucyl peptides + H2O not in vitro 3.4.21.53 acid resistance regulator GdE protein + H2O degradation of GadE protein by Lon rapidly terminates the acid resistance response upon shift back to neutral pH and avoids overexpression of acid resistance genes in stationary phases 3.4.21.53 alpha-casein + H2O - 3.4.21.53 apoTorA + H2O a molybdoenzyme; immature TorA (apoTorA) is degraded in vivo and in vitro by the Lon protease. Enzyme Lon interacts with apoTorA but not with holoTorA. Enzyme Lon and TorD, the specific chaperone of TorA, compete for apoTorA binding, but TorD binding protects apoTorA against degradation 3.4.21.53 Bacteriophage lambda N-protein + H2O - 3.4.21.53 calpain 10 + H2O degradation of the mitochondrial matrix protease 3.4.21.53 Canavanine-containing proteins + H2O not in vitro 3.4.21.53 CysB + H2O a positive cysDNC operon transcription regulator 3.4.21.53 CysD + H2O a subunit of the sulfate adenylyltransferase, low activity 3.4.21.53 cystathionine beta-synthase + H2O when misfolded or unfolded 3.4.21.53 cytochrome c oxidase 4 isoform 1 + H2O i.e. COX4-1 3.4.21.53 cytochrome c oxidase subunit + H2O - 3.4.21.53 glutaminase C + H2O when misfolded or unfolded 3.4.21.53 GlyA + H2O a protein of the MetR regulon 3.4.21.53 HrpG + H2O the degradation tag is located at the N-terminus of the substrate. The N-terminal moiety of HrpG is required for Lon recognition 3.4.21.53 IbpA + H2O - 3.4.21.53 LasI + H2O Lon is involved in the regulation of quorum-sensing signaling systems in Pseudomonas aeruginosa, the opportunistic human pathogen. The enzyme is part of the acyl-homoserine lactone-mediated QS system LasR/LasI, but LasR/LasI regulation is independent of the RhlR/RhlI system by Lon. QS systems are organized hierarchically: the RhlR/RhlI system is subordinate to LasR/LasI, Lon represses the expression of LasR/LasI by degrading LasI, an HSL synthase, leading to negative regulation of the RhlR/RhlI system, overview 3.4.21.53 MetR + H2O a protein of the MetR regulon, transcriptional regulator of metE expression 3.4.21.53 Mgm101 + H2O a yeast mitochondrial protein 3.4.21.53 mitochondrial aconitase + H2O essential enzyme, particularly susceptible to oxidative damage, preferentially oxidatively modified and inactivated during ageing 3.4.21.53 mitochondrial aconitase + H2O when misfolded or unfolded 3.4.21.53 mitochondrial transcription factor A + H2O i.e. TFAM 3.4.21.53 additional information - 3.4.21.53 additional information ATP-dependent serine protease 3.4.21.53 additional information involved in mitochondrial protein turnover 3.4.21.53 additional information essential for growth of yeast on nonfermentable carbon sources 3.4.21.53 additional information ATP stimulated protease may be an essential defence against the stress of life in an oxygen environment 3.4.21.53 additional information rapid proteolysis plays a major role in post-translational cellular control by the targeted degradation of short-lived regulatory proteins 3.4.21.53 additional information recognition and selective degradation of abnormal and unstable proteins 3.4.21.53 additional information regulation of several important cellular functions, including radiation resistance, cell division, filamentation, capsular polysaccharide production, lysogeny of certain bacteriophages, and proteolytic degradation of certain regulatory and abnormal proteins 3.4.21.53 additional information required for expression of intron-containing genes in mitochondria, required for selective proteolysis in the matrix, maintenance of mitochondrial DNA, and respiration-dependent growth 3.4.21.53 additional information required for mitochondrial function 3.4.21.53 additional information required for selective proteolysis in the matrix, maintenance of mitochondrial DNA, and respiration-dependent growth 3.4.21.53 additional information required for selective proteolysis in the matrix, maintenance of mitochondrial DNA, and respiration-dependent growth, protein degradation in mitochondrial homeostasis 3.4.21.53 additional information enzyme and protease Clp participate in the physiological disintegration of cytoplasmic inclusion bodies, their absence minimizing the protein removal up to 40%. Clp takes the major and enzyme a minor role in processing of aggregation-prone proteins and also of polypeptides physiologically released from inclusion bodies 3.4.21.53 additional information enzyme is required for proper expression, assembly or function of the VirB/D4-mediated T-DNA transfer system 3.4.21.53 additional information enzyme participates directly in the metabolism of mitochondrial DNA 3.4.21.53 additional information proteases ClpXP and Lon contribute to the environmental regulation of type III secretion system T3SS through regulated proteolysis of small histone-like protein YmoA 3.4.21.53 additional information construct containing residues 793-1133 of yeast lon, which comprises the proteolytic domain along with most of the alpha-domain, exhibits low but significant proteolytic activity in vivo 3.4.21.53 additional information lon interacts with the mitochondrial genome in cultured cells. Associates with sites distributed primarily within one-half of the genome and preferentially with the control region for mitochondrial DNA replication and transcription, which has a G-rich consensus sequence 3.4.21.53 additional information the polyphosphate-lon complex does not degrade intact native ribosomes 3.4.21.53 additional information protease Lon recognizes specific sequences rich in aromatic residues that are accessible in unfolded polypeptides but hidden in most native structures. Denatured polypeptides lacking such sequences are poor substrates. Lon also unfolds and degrades stably folded proteins with accessible recognition tags. Lon can recognize multiple signals in unfolded polypeptides synergistically, resulting in nanomolar binding and a mechanism for discriminating irreversibly damaged proteins from transiently unfolded elements of structure 3.4.21.53 additional information protease Lon represses the expression of LasR/LasI by degrading HSL synthase LasI, leading to negative regulation of the RhlR/RhlI system. RhlI/RhlR is also regulated by Lon independently of LasI/LasR 3.4.21.53 additional information substrate specificity of isoforms LonA, LonB and of protease Clp can be determined, in part, by the spatial and temporal organization of the proteases in vivo 3.4.21.53 additional information homooligomeric ATP-dependent LonA proteases are bifunctional enzymes 3.4.21.53 additional information repeated cycles of ATP binding and hydrolysis power conformational changes that pull the tag through the pore and eventually tug the native portion of the substrate against the AAA+ ring, creating an unfolding force. Depending on the native substrate and enzyme, successful unfolding can require anywhere from a few to many hundreds of cycles of ATP hydrolysis 3.4.21.53 additional information the enzyme and sirtuin 3 interact, but sirtuin 3 is not a substrate for Lon activity 3.4.21.53 additional information a quantitative Super-SILAC (stable isotope labeling with amino acids in cell culture) mass spectrometry approach and analysis of proteomes of a lon mutant and a strain producing the protease are employed to determine substrate specificity and Lon-dependent physiological functions. The recognition mechanisms of known Lon substrates are highly diverse. Misfolded proteins are mainly recognized by short, hydrophobic stretches normally buried in the core of natively folded proteins. In contrast, recognition of SulA occurs via its C-terminus with a critical histidine and tyrosine at its very end 3.4.21.53 additional information Escherichia coli Lon binds both single stranded DNA (ssDNA) and RNA (ssRNA), and double stranded DNA (dsDNA) in a non-specific manner, and this interaction enhances Lon ATPase and proteolytic activities 3.4.21.53 additional information Lon binding partners are NADH dehydrogenase ubiquinone iron-sulfur protein 8 (NDUFS8), heat shock protein (Hsp)-60, and mtHsp70 3.4.21.53 MrpL32 + H2O human MrpL32, a component of the 39S large subunit of the mitochondrial ribosome 3.4.21.53 Mutant form of alkaline phosphatase PhoA61 + H2O not in vitro 3.4.21.53 Proteins with highly abnormal conformation + H2O one of the heat-shock proteins under control of rpoH operon(htp R) 3.4.21.53 Proteins with highly abnormal conformation + H2O rate-limiting step in breakdown of highly abnormal and some normal proteins 3.4.21.53 Proteins with highly abnormal conformation + H2O catalyzes inital step in the degradation of proteins with abnormal conformation as may result from nonsense or missense mutations, biosynthetic errors or intracellular denaturation 3.4.21.53 RcsA + H2O - 3.4.21.53 RcsA + H2O protein degradation mediates the turnover of damaged proteins 3.4.21.53 ribosomal S2 protein + H2O - 3.4.21.53 steroidogenic acute regulatory protein + H2O - 3.4.21.53 SulA + H2O - 3.4.21.53 SulA + H2O physiological substrate SulA3-169 and SulA23-169 3.4.21.53 SulA + H2O inactivation of SulA through the enzyme in vivo requires binding to the N domain and robust ATP hydrolysis but does not require degradation or translocation into the proteolytic chamber 3.4.21.53 SulA + H2O a cell division inhibitor 3.4.21.53 TFAM + H2O only DNA-free TFAM is a substrate for human mitochondrial Lon. TFAM is released from DNA upon phosphorylation by protein kinase A, and TFAM not bound to DNA, whether phosphorylated or not, is a substrate for the ATP-dependent mitochondrial Lon protease 3.4.21.53 tmRNA-tagged protein + H2O - 3.4.21.53 TrfA + H2O - 3.4.21.53 Twinkle helicase + H2O a human mitochondrial protein 3.4.21.53 ZntR + H2O -