Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.6 (RNA polymerase)
 34,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The isolation from bovine seminal plasma and purification of a new protein called 'antiseminalplasmin', which reverses the inhibition of the growth of, and RNA synthesis in, Escherichia coli by seminalplasmin (another protein of bovine seminal plasma), is described. Antiseminalplasmin, a weakly acidic protein, has a minimum Mr of about 39 000 and appears to consist of three acidic peptide chains that move close to each other on electrophoresis on cellulose acetate strips or on sodium dodecyl sulphate/18%-(w/v)-polyacrylamide gels. Antiseminalplasmin has a tendency to oligomerize at slightly alkaline pH values; it does not bind to seminalplasmin or to DNA, and does not reverse the inhibition by seminalplasmin of transcription in vitro by purified E. coli RNA polymerase. It appears that antiseminalplasmin may act by binding to the cell surface and preventing the entry of seminalplasmin into the cells. By itself, antiseminalplasmin has no effect on the growth of E. coli.
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PMID:Isolation, characterization and possible mode of action of antiseminalplasmin, a new protein that inhibits the antimicrobial activity of seminalplasmin. 240 4

The duplex DNA unwinding ability of seminalplasmin [corrected] from bovine semen was examined by treatment of plasmid-protein complexes with calf thymus topoisomerase I and resolution of the topoisomer distributions by agarose gel electrophoresis. Binding of seminalplasmin [corrected] results in a moderate degree of unwinding of supercoiled plasmid. The elongation of the RNA chain by E. coli RNA polymerase over promoter containing template is not inhibited by seminalplasmin [corrected]. However, the reinitiation of transcription is blocked in such cases indicating that seminalplasmin [corrected] inhibits transcription by binding to the initiation site of RNA polymerase.
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PMID:Bovine seminalplasmin [corrected] is a DNA unwinding protein. 283 34

The interaction of bovine seminalplasmin and rifampicin with E. coli RNA polymerase was studied using fluorescence spectroscopy. Both seminalplasmin and rifampicin are known to be the inhibitors for the initiation of RNA synthesis in E. coli. Rifampicin quenced the intrinsic fluorescence of RNA polymerase and seminalplasmin when excited at 280 nm. However, excess of seminalplasmin reversed the quenching of RNA polymerase fluorescence by rifampicin. Upon addition of rifampicin to the seminalplasmin-RNA polymerase complex, no change in fluorescence spectrum was observed. It appeared that although rifampicin could form complexes with RNA polymerase and seminalplasmin alone, no binding domain was available for rifampicin in the RNA polymerase-seminalplasmin complex. These observations are discussed in the light of the 'initiation site' of E. coli RNA polymerase.
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PMID:Interaction of bovine seminalplasmin with Escherichia coli RNA polymerase in the presence of rifampicin. 388 59