[Specific modification of the alpha-subunit of Escherichia coli Rna polymerase by monomercuric derivative of fluorescein mercuric acetate].
The method for specific modification of Escherichia coli RNA polymerase by a monomercuric derivative of fluorescein--fluoresceinmonomercuracetate (FMMA)--a specific reagent for SH-groups of proteins is suggested. It is shown, that in conditions of equimolar FMMA/enzyme ratio the fluorescent label interacts preferantially with a single sulfhydryl group in alpha-subunit of RNA polymerase. The mercaptide bonding formation is followed by significant alterations of all spectral parameters of FMMA, but has no effect on the kinetic parameters (KB and k2) of RNA synthesis initiation nor does it lead to inhibition of the total RNA synthesis. The modification presented may be used in structural and topological investigations of RNA polymerase functioning.
Ozolin'
O N
ON
Uteshev
T A
TA
Kim
Iu A
IuA
Deev
A A
AA
Kamzolova
S G
SG
D001665:Binding Sites; D012321:DNA-Directed RNA Polymerases / Q000187:drug effects / Q000378:metabolism*; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology*; D005452:Fluoresceins / Q000494:pharmacology*; D007700:Kinetics; D046911:Macromolecular Substances; D009941:Organomercury Compounds / Q000494:pharmacology*; D013050:Spectrometry, Fluorescence; D013438:Sulfhydryl Compounds / Q000378:metabolism
D005452:Fluoresceins; D046911:Macromolecular Substances; D009941:Organomercury Compounds; D013438:Sulfhydryl Compounds; C001673:fluorescein mercuric acetate; D012321:DNA-Directed RNA Polymerases
Spetsificheskaia modifikatsiia alpha-sub''edinitsy RNK-polimerazy Escherichia coli monortutnym proizvodnym fluorestseinmerkuratsetata.