DNK giraza

DNK giraza
Dimer DNK topoizomeraze IIA (čovjek)
Identifikatori
EC broj 5.99.1.3
CAS broj 142805-56-9
IntEnz IntEnz view
BRENDA BRENDA entry
ExPASy NiceZyme view
KEGG KEGG entry
MetaCyc metabolic pathway
PRIAM profile
PDB RCSB PDB PDBe PDBj PDBsum
Pretraga
PMC articles
PubMed articles
NCBI Protein search

DNK giraza je enzim koji umanjuje naprezanje tokom odvijanja dvolančane DNK helikazom. To dovodi do negativnog supernamotavanja DNK. Bakterijska DNK giraza je biološka meta mnogih antibiotika, neki od kojih su nalidiksilna kiselina, novobiocin, i ciprofloksacin.

DNK giraza je tip II topoizomeraza (EC 5.99.1.3) koja uvodi negativne supernamotaje (ili relaksira pozitivne supernamotaje) u DNK. Ona savija templet tako da se formira ukrštanje, zatim preseca jedan od dvostrukih heliksa i propušta drugi kroz taj otvor. Taj proces se odvija kod prokariota (posebno kod bakterija). Nedavno je giraza je nađena kod apikoplast malerijskog parazita Plasmodium falciparum, jednoćelijskog eukariota.

Literatura

  • Nicholas C. Price, Lewis Stevens (1999). Fundamentals of Enzymology: The Cell and Molecular Biology of Catalytic Proteins (Third izd.). USA: Oxford University Press. ISBN 019850229X. 
  • Eric J. Toone (2006). Advances in Enzymology and Related Areas of Molecular Biology, Protein Evolution (Volume 75 izd.). Wiley-Interscience. ISBN 0471205036. 
  • Branden C, Tooze J.. Introduction to Protein Structure. New York, NY: Garland Publishing. ISBN: 0-8153-2305-0. 
  • Irwin H. Segel. Enzyme Kinetics: Behavior and Analysis of Rapid Equilibrium and Steady-State Enzyme Systems (Book 44 izd.). Wiley Classics Library. ISBN 0471303097. 
  • Robert A. Copeland (2013). Evaluation of Enzyme Inhibitors in Drug Discovery: A Guide for Medicinal Chemists and Pharmacologists (2nd izd.). Wiley-Interscience. ISBN 111848813X. 
  • Gerhard Michal, Dietmar Schomburg (2012). Biochemical Pathways: An Atlas of Biochemistry and Molecular Biology (2nd izd.). Wiley. ISBN 0470146842. 
  • Molecular Cloning of Apicoplast-Targeted Plasmodium falciparum DNA Gyrase Genes: Unique Intrinsic ATPase Activity
  • ATP-Independent Dimerization of PfGyrB Subunit.(2007)EUKARYOTIC CELL, Mar. 2007, p. 398–412
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5.99.1
B enzm: 1.1/2/3/4/5/6/7/8/10/11/13/14/15-18, 2.1/2/3/4/5/6/7/8, 2.7.10, 2.7.11-12, 3.1/2/3/4/5/6/7, 3.1.3.48, 3.4.21/22/23/24, 4.1/2/3/4/5/6, 5.1/2/3/4/99, 6.1-3/4/5-6
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Separacija
i inicijacija
Prokariotska
(inicijacija)
Eukariotska
(priprema u
G1 fazi)
Oba
Replikacija
Prokariotska
(elongacija)
Eukariotska
(sinteza u
S fazi)
Oba
Kretanje: Procesivnost  DNK ligaza
Terminacija
B bsyn: dnk (repl, cycl, reco, repr)  tscr (fact, tcrg, nucl, rnat, rept, ptts)  tltn (risu, pttl, nexn)  dnab, rnab/runp  stru (domn, 1°, 2°, 3°, 4°)
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Teme
Tipovi
EC1 Oksidoreduktaze/spisak  • EC2 Transferaze/spisak  • EC3 Hidrolaze/spisak  • EC4 Lijaze/spisak  • EC5 Izomeraze/spisak  • EC6 Ligaze/spisak
B enzm: 1.1/2/3/4/5/6/7/8/10/11/13/14/15-18, 2.1/2/3/4/5/6/7/8, 2.7.10, 2.7.11-12, 3.1/2/3/4/5/6/7, 3.1.3.48, 3.4.21/22/23/24, 4.1/2/3/4/5/6, 5.1/2/3/4/99, 6.1-3/4/5-6