ID KAIC3_SYNY3 Reviewed; 505 AA. AC P74503; DT 11-OCT-2004, integrated into UniProtKB/Swiss-Prot. DT 01-FEB-1997, sequence version 1. DT 27-MAR-2024, entry version 136. DE RecName: Full=Circadian clock protein KaiC3 {ECO:0000303|PubMed:23449916}; DE EC=2.7.11.1 {ECO:0000305|PubMed:23449916}; DE EC=3.6.4.- {ECO:0000269|PubMed:31767776}; GN Name=kaiC3 {ECO:0000303|PubMed:23449916, ECO:0000303|PubMed:25139948}; GN OrderedLocusNames=slr1942; OS Synechocystis sp. (strain PCC 6803 / Kazusa). OC Bacteria; Cyanobacteriota; Cyanophyceae; Synechococcales; Merismopediaceae; OC Synechocystis. OX NCBI_TaxID=1111708; RN [1] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=PCC 6803 / Kazusa; RX PubMed=8905231; DOI=10.1093/dnares/3.3.109; RA Kaneko T., Sato S., Kotani H., Tanaka A., Asamizu E., Nakamura Y., RA Miyajima N., Hirosawa M., Sugiura M., Sasamoto S., Kimura T., Hosouchi T., RA Matsuno A., Muraki A., Nakazaki N., Naruo K., Okumura S., Shimpo S., RA Takeuchi C., Wada T., Watanabe A., Yamada M., Yasuda M., Tabata S.; RT "Sequence analysis of the genome of the unicellular cyanobacterium RT Synechocystis sp. strain PCC6803. II. Sequence determination of the entire RT genome and assignment of potential protein-coding regions."; RL DNA Res. 3:109-136(1996). RN [2] RP PROBABLE CATALYTIC ACTIVITY, AUTOPHOSPHORYLATION ACTIVITY, SUBUNIT, AND RP PUTATIVE PHOSPHORYLATION AT SER-423 AND THR-424. RC STRAIN=PCC 6803 / Kazusa; RX PubMed=23449916; DOI=10.1099/mic.0.065425-0; RA Wiegard A., Doerrich A.K., Deinzer H.T., Beck C., Wilde A., RA Holtzendorff J., Axmann I.M.; RT "Biochemical analysis of three putative KaiC clock proteins from RT Synechocystis sp. PCC 6803 suggests their functional divergence."; RL Microbiology 159:948-958(2013). RN [3] RP DISRUPTION PHENOTYPE. RC STRAIN=PCC 6803 / Kazusa; RX PubMed=25139948; DOI=10.1099/mic.0.081695-0; RA Doerrich A.K., Mitschke J., Siadat O., Wilde A.; RT "Deletion of the Synechocystis sp. PCC 6803 kaiAB1C1 gene cluster causes RT impaired cell growth under light-dark conditions."; RL Microbiology 160:2538-2550(2014). RN [4] RP FUNCTION, ATPASE ACTIVITY, ACTIVITY REGULATION, BIOPHYSICOCHEMICAL RP PROPERTIES, INTERACTION WITH ITSELF; KAIB1; KAIB3 AND KAIC1, RP PHOSPHORYLATION, DISRUPTION PHENOTYPE, AND MUTAGENESIS OF 423-SER-THR-424. RC STRAIN=PCC 6803 / Kazusa; RX PubMed=31767776; DOI=10.1128/jb.00478-19; RA Wiegard A., Koebler C., Oyama K., Doerrich A.K., Azai C., Terauchi K., RA Wilde A., Axmann I.M.; RT "Synechocystis KaiC3 Displays Temperature- and KaiB-Dependent ATPase RT Activity and Is Important for Growth in Darkness."; RL J. Bacteriol. 202:0-0(2020). CC -!- FUNCTION: Seems to be linked to dark adaption of Synechocystis cells, CC but is not as essential as the core oscillator KaiAB1C1 for the CC circadian cycle (PubMed:31767776). KaiB3 and KaiC3 may cross talk with CC the core oscillator (PubMed:31767776) (Probable). Autophosphorylates CC and dephosphorylates independently of KaiA (PubMed:23449916). Has a CC weak ATPase, hydrolyzes 8.5 ATP/monomer/day, has no detectable ATP CC synthesis activity. ATPase activity reduced 55% by KaiB3 monomer but CC not the KaiB3 tetramer or KaiA in vitro, reduced 35% by KaiB1 tetramer CC (PubMed:31767776). {ECO:0000269|PubMed:23449916, CC ECO:0000269|PubMed:31767776, ECO:0000305|PubMed:31767776}. CC -!- CATALYTIC ACTIVITY: CC Reaction=ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl- CC [protein]; Xref=Rhea:RHEA:17989, Rhea:RHEA-COMP:9863, Rhea:RHEA- CC COMP:11604, ChEBI:CHEBI:15378, ChEBI:CHEBI:29999, ChEBI:CHEBI:30616, CC ChEBI:CHEBI:83421, ChEBI:CHEBI:456216; EC=2.7.11.1; CC Evidence={ECO:0000305|PubMed:23449916}; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:17990; CC Evidence={ECO:0000305|PubMed:23449916}; CC -!- CATALYTIC ACTIVITY: CC Reaction=ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L- CC threonyl-[protein]; Xref=Rhea:RHEA:46608, Rhea:RHEA-COMP:11060, CC Rhea:RHEA-COMP:11605, ChEBI:CHEBI:15378, ChEBI:CHEBI:30013, CC ChEBI:CHEBI:30616, ChEBI:CHEBI:61977, ChEBI:CHEBI:456216; CC EC=2.7.11.1; Evidence={ECO:0000305|PubMed:23449916}; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:46609; CC Evidence={ECO:0000305|PubMed:23449916}; CC -!- CATALYTIC ACTIVITY: CC Reaction=ATP + H2O = ADP + H(+) + phosphate; Xref=Rhea:RHEA:13065, CC ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:30616, CC ChEBI:CHEBI:43474, ChEBI:CHEBI:456216; CC Evidence={ECO:0000269|PubMed:31767776}; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:13066; CC Evidence={ECO:0000269|PubMed:31767776}; CC -!- ACTIVITY REGULATION: ATPase activity is influenced by KaiB1 and KaiB3 CC in vitro; ATPase is reduced 35% by the KaiB1 tetramer and 55% by the CC KaiB3 monomer but not affected by KaiA or the KaiB3 tetramer. CC {ECO:0000269|PubMed:31767776}. CC -!- BIOPHYSICOCHEMICAL PROPERTIES: CC Temperature dependence: CC ATPase activity is not temperature compensated, unlike the circadian CC oscillator, its activity increases with increasing temperature. CC {ECO:0000269|PubMed:31767776}; CC -!- SUBUNIT: Multimerizes, probably forming homohexamers, no interaction CC with KaiC1 or KaiC2 is seen (PubMed:23449916). In another study forms CC hexamers, interacts with KaiB1, KaiB3, and KaiC1 (PubMed:31767776). CC {ECO:0000269|PubMed:23449916, ECO:0000269|PubMed:31767776}. CC -!- DOMAIN: In the homohexamer the 2 domains (called CI and CII) self- CC associate to each form a 'donut' layer; the compactness and local CC conformation of the domains varies over the cell cycle and impacts CC function. CII has the autokinase and autophosphatase activities, both CC CI and CII have (weak) ATPase activity. {ECO:0000305}. CC -!- PTM: Autophosphorylates and dephosphorylates (PubMed:23449916, CC PubMed:31767776). Dephosphorylation of KaiC3 was higher at 25 than at CC 30 or 35 degrees Celsius (PubMed:31767776). CC {ECO:0000269|PubMed:23449916, ECO:0000269|PubMed:31767776}. CC -!- DISRUPTION PHENOTYPE: No visible phenotype under photoautotrophic CC conditions in continuous light or in a light/dark regime with or CC without 0.2% glucose (PubMed:25139948). Growth in the dark (with CC glucose) is more impaired than in wild type (PubMed:31767776). CC {ECO:0000269|PubMed:25139948, ECO:0000269|PubMed:31767776}. CC -!- SIMILARITY: Belongs to the KaiC family. {ECO:0000305}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; BA000022; BAA18607.1; -; Genomic_DNA. DR PIR; S76478; S76478. DR AlphaFoldDB; P74503; -. DR SMR; P74503; -. DR IntAct; P74503; 2. DR STRING; 1148.gene:10499490; -. DR PaxDb; 1148-1653695; -. DR EnsemblBacteria; BAA18607; BAA18607; BAA18607. DR KEGG; syn:slr1942; -. DR eggNOG; COG0467; Bacteria. DR InParanoid; P74503; -. DR PhylomeDB; P74503; -. DR Proteomes; UP000001425; Chromosome. DR GO; GO:0005524; F:ATP binding; IEA:InterPro. DR GO; GO:0003677; F:DNA binding; IEA:InterPro. DR GO; GO:0016787; F:hydrolase activity; IEA:UniProtKB-KW. DR GO; GO:0000287; F:magnesium ion binding; IEA:InterPro. DR GO; GO:0004674; F:protein serine/threonine kinase activity; IEA:InterPro. DR GO; GO:0016310; P:phosphorylation; IEA:UniProtKB-KW. DR GO; GO:0042752; P:regulation of circadian rhythm; IEA:InterPro. DR GO; GO:0006355; P:regulation of DNA-templated transcription; IEA:InterPro. DR CDD; cd19485; KaiC-N; 1. DR CDD; cd19484; KaiC_C; 1. DR Gene3D; 3.40.50.300; P-loop containing nucleotide triphosphate hydrolases; 2. DR InterPro; IPR013503; Circadian_KaiC_bact. DR InterPro; IPR030665; KaiC. DR InterPro; IPR014774; KaiC-like_dom. DR InterPro; IPR047222; KaiC_C. DR InterPro; IPR010624; KaiC_dom. DR InterPro; IPR047221; KaiC_N. DR InterPro; IPR027417; P-loop_NTPase. DR NCBIfam; TIGR02655; circ_KaiC; 1. DR PANTHER; PTHR42926; -; 1. DR PANTHER; PTHR42926:SF1; KAIC-LIKE PROTEIN 2; 1. DR Pfam; PF06745; ATPase; 2. DR PIRSF; PIRSF039117; KaiC; 1. DR SUPFAM; SSF52540; P-loop containing nucleoside triphosphate hydrolases; 2. DR PROSITE; PS51146; KAIC; 2. PE 1: Evidence at protein level; KW Hydrolase; Kinase; Phosphoprotein; Reference proteome; Repeat; Transferase. FT CHAIN 1..505 FT /note="Circadian clock protein KaiC3" FT /id="PRO_0000217788" FT DOMAIN 10..252 FT /note="KaiC 1" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00487" FT DOMAIN 253..485 FT /note="KaiC 2" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00487" FT MOD_RES 423 FT /note="Phosphoserine; by autocatalysis" FT /evidence="ECO:0000305|PubMed:23449916" FT MOD_RES 424 FT /note="Phosphothreonine; by autocatalysis" FT /evidence="ECO:0000305|PubMed:23449916" FT MUTAGEN 423..424 FT /note="ST->AA: 2-fold increase in ATPase." FT /evidence="ECO:0000269|PubMed:31767776" FT MUTAGEN 423..424 FT /note="ST->DE: No change in ATPase." FT /evidence="ECO:0000269|PubMed:31767776" SQ SEQUENCE 505 AA; 56175 MW; 543E1F00F1B6BAE0 CRC64; MIDQETDGIE KLETGIPGFD FLSDGGLPLG RATLIAGTAG SAKTIFASQF LVEGIQRGEN GVFVTFEEPP KALRKNMRGF GWDIQQWENE GKWVFVDASP QPGDRPIVSG EYDLGALIAR IEHAVRKYKA SRISLDSLGA IFSHLSDSAQ VRSDLFRLAS ALRELGVTAI MTAERVEEYG EISRYGVEEF VADNVVIVRN VLADEKRRRT IEILKYRGTD HQKGEFPFTI INKKGIVIIP LSAIELEQKS SDIRITSGSE ELDRMCGSGF FRDSIILVSG ATGTGKTLMV TEFMDGGVAN GERCLVFAFE ESREQLIRNA TGWGVDFKQM EKEGKLKVVC RYPETTNLEN HLIMMKDIIQ EFKPNRVAVD SLSALERVST LKSFREFIIG LTSFIKQQEI GGLFTSTTPN LLGGASITDA HISTITDSII LLRYVEMYGE MRRGITVLKM RGSMHDKDIR EFSIDHQGMH IGKPFRNVTG ILAGTPMYTA QSEVERLSGL FDEKI //