[Isolation and partial characterization of DNA topoisomerase I from the nucleoids of white mustard chloroplasts].
DNA topoisomerase was isolated for the first time from nucleoids of white mustard (Sinapis alba L.) chloroplasts. The enzyme had a molecular weight of 70 kDa; it was ATP-independent, required the presence of mono- (K+) and bivalent (Mg2+) cations, and was capable of relaxing both negatively and positively supercoiled DNA. These results suggest that the enzyme isolated belongs to type IB DNA topoisomerases.
Bach Institute of Biochemistry, Russian Academy of Sciences, Leninskii pr. 33, Moscow, 119071 Russia.
G G
GG
Belkina
E V
EV
Pogul'skaia
N P
NP
Iurina
D002412:Cations; D002467:Cell Nucleus / Q000201:enzymology; D002498:Centrifugation; D002736:Chloroplasts / Q000201:enzymology*; D004264:DNA Topoisomerases, Type I / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D004278:DNA, Superhelical / Q000737:chemistry / Q000378:metabolism; D008274:Magnesium; D008970:Molecular Weight; D010957:Plasmids; D011188:Potassium; D031226:Sinapis / Q000201:enzymology*
D002412:Cations; D004278:DNA, Superhelical; D004264:DNA Topoisomerases, Type I; D008274:Magnesium; D011188:Potassium