Protein: Reverse gyrase subunit A (Q74MA4)
Organism: Nanoarchaeum equitans (strain Kin4-M)
Function: Modifies the topological state of DNA by introducing positive supercoils in an ATP-dependent process. Binds to single-stranded DNA, transiently cleaves and then rejoins the end, introducing a positive supercoil in the process. The scissile phosphodiester is attacked by the catalytic tyrosine of the enzyme, resulting in the formation of a DNA-(5'-phosphotyrosyl)-enzyme intermediate. Probably involved in rewinding DNA strands in regions of the chromosome that have opened up to allow replication, transcription, DNA repair or for DNA protection (Probable). Reconstituted holoenzyme binds dsDNA a bit better than ssDNA, this subunit preferentially binds ssDNA . In isolation this subunit relaxes negatively- supercoiled DNA, and stimulates the endogenous ATPase activity of the RgyB subunit
Subcellular location: Cytoplasm
InterPro domains:
- IPR013826: DNA topoisomerase, type IA, central region, subdomain 3 (homologous_superfamily) [315-438]
- IPR003602: DNA topoisomerase, type IA, DNA-binding domain (domain) [305-554]
- IPR013824: DNA topoisomerase, type IA, central region, subdomain 1 (homologous_superfamily) [218-595]
- IPR034142: Reverse gyrase, TOPRIM domain (domain) [41-209]
- IPR013497: DNA topoisomerase, type IA, central (domain) [161-602]
- IPR023405: DNA topoisomerase, type IA, core domain (homologous_superfamily) [36-601]
- IPR005736: Reverse gyrase (family) [2-601]
- IPR003601: DNA topoisomerase, type IA, domain 2 (domain) [188-276]
- IPR006171: TOPRIM domain (domain) [41-197]
Sequence:
MLRLEEIDLDTIKKELDEERKKVEEIMKGNIPTEIKDLIKMVLFIVESPNKARTIANFFGKPSVRRIGNIKAYETTTGKYILTIVATKGHLFELTLKEEGVYGVLKEKEYVPIFSPIKKCLDCGHQFVDEDKCPRCGSENIDDASDRIKVLRDLAQEADIVLIGTDPDAEGEKIAYDVYSIIRPYNKNIYRAEFHEVTRQAIIKALEEIRDINTNRVKAQLVRRIEDRWIGFALSQRLWSRFKKKTLSAGRVQTPVLGFIIKRYEEYKKNRAHYYAVKTSDFEVTFISDDPLEKYDKTIKIEKIEEKESEKKPLPPYTTDSLLRDAVIELRLSVDKIMALAQNLFEWGLITYHRTDSTHISNLGIQIAQTYIENTFGKEYFYPRHWGEEGTHEAIRPTKPIDTETLIKMLREGDIQIQGITKEHIRLYDLIFRRFIASQMKPFIAIETKFNAVWSNLNTTIEGITDIKENGWNLIKPIKLLAIKEGEYEVIDVKHWIGSKVPLYTQADVIELMKEQNIGRPSTYATIVKKLFERYYVIEKNQRLIPTERGIKVYQYLTERFGHLVDVKLTADLLEKMDRIENGELDYMDVLRSFKKELIEIWKTKETKYIADGIYKWKEYSVPAIVYERYEKILKRKKVYPEYLTPWSRAIYNALPLDNEIEKQTLALAIEKDFEILTKKPILREYKKKYEHLKNLVDQLL
Predicted GO terms:
Molecular Function (MF): GO:0003674 (molecular function), GO:0005488 (binding), GO:0003824 (catalytic activity), GO:0016853 (isomerase activity), GO:0140640 (catalytic activity, acting on a nucleic acid), GO:0005515 (protein binding), GO:0003916 (DNA topoisomerase activity), GO:0140097 (catalytic activity, acting on DNA), GO:0003917 (DNA topoisomerase type I (single strand cut, ATP-independent) activity)
Biological Process (BP): GO:0008150 (biological process), GO:0008152 (metabolic process), GO:0009987 (cellular process), GO:0044237 (cellular metabolic process), GO:0071704 (organic substance metabolic process), GO:0044238 (primary metabolic process), GO:0006807 (nitrogen compound metabolic process), GO:0006725 (cellular aromatic compound metabolic process), GO:0034641 (cellular nitrogen compound metabolic process), GO:1901360 (organic cyclic compound metabolic process), GO:0044260 (cellular macromolecule metabolic process), GO:0006139 (nucleobase-containing compound metabolic process), GO:0043170 (macromolecule metabolic process), GO:0046483 (heterocycle metabolic process), GO:0006259 (DNA metabolic process), GO:0090304 (nucleic acid metabolic process), GO:0006265 (DNA topological change)
Cellular Component (CC): GO:0005575 (cellular component), GO:0032991 (protein-containing complex), GO:1902494 (catalytic complex), GO:0140535 (intracellular protein-containing complex)