Transcription requires that RNA polymerase binds to promoters buried in nonspecific sites on DNA. The search for may be facilitated if the slides along molecule of Single molecules Escherichia coli were visualized, and their movements immobilized bacteriophage λ T7 DNAs examined. Deviating from drifts by bulk flow, about 40 percent enzyme moved extended results provide direct evidence sliding as a mechanism relocation

Evidence for sliding of proteins along DNA has been provided by many kinetic studies, but single-molecule-based measurements have uncovered distinct problems, the solutions which may lead us to an understanding new mechanisms gene regulation. Furthermore, they reveal a deep problem lying between chemistry and physics regarding seemingly simple binding protein. Single-molecule dynamics provides tool solve this without prejudgments or unsound assumptions. is most powerful, probably only...

The authors have previously reported that the electrostatic orientation and dielectrophoresis (DEP) of DNA occur under /spl ap/1 MHz, >1/spl times/10/sup 6/ V/m field, by which strands are stretched straight along field lines positioned onto electrode edges. This paper presents some application this stretch-and-positioning method to genetic engineering. It is shown size distribution, as well activities nuclease, can be determined measurement apparent length DNA. Several methods developed...

The authors have previously reported that the electrostatic orientation and dielectrophoresis (DEP) of DNA occur under a approximately=1 MHz, >1*10/sup 6/ V/m field, by which strands are stretched straight along field lines positioned onto electrode edges. In present work they discuss some applications this stretch-and-positioning method to genetic engineering. It is shown size distribution, as well activities nuclease, can be determined measurement apparent length DNA. Several methods...

A unique nanoelectronic platform, based on single-walled carbon nanotubes (SWNTs), has been fabricated for measuring electrical transport in single-molecule DNA. We have tested 80 base pairs of single- and double-stranded DNA (ssDNA dsDNA, respectively) complex sequences. About a 25−40 pA current (at 1 V) was measured the dsDNA molecule covalently attached to SWNT electrode at its termini. In absence pair stacking, ssDNA carries feeble ∼1 or less. Gate-voltage-dependent I−V characteristics...

A novel method for the space-resolved dissection (molecular surgery) of deoxyribonucleic acid (DNA) using electrostatic molecular manipulation is proposed and demonstrated. In conventional biochemistry, DNA-cutting enzymes DNA are mixed in water, so cutting reactions occur only by stochastic chances. contrast, present based upon a physical enables reproducible at any desired position along molecule. order to realize this cutting, target stretched straight orientation anchored on solid...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSpectral evidence for a rapidly formed structural intermediate in the refolding kinetics of hen egg-white lysozymeShingo Kato, Motoyoshi Okamura, Nobuo Shimamoto, and Hiroyasu UtiyamaCite this: Biochemistry 1981, 20, 5, 1080–1085Publication Date (Print):March 1, 1981Publication History Published online1 May 2002Published inissue 1 March 1981https://pubs.acs.org/doi/10.1021/bi00508a006https://doi.org/10.1021/bi00508a006research-articleACS...

Yeast peroxisomes were purified to near homogeneity from cells of Candida tropicalis grown on oleic acid for the purpose examining possible presence DNA in this organelle. The purification procedure includes effective conversion spheroplasts with Zymolyase and sodium sulfite separation organelles at extremely low ionic strength. mitochondrial contamination was less than 1%, based several criteria, yield about 40%. peroxisomal fraction contained a very small amount DNA, which yielded...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTIdentification and characterization of the direct folding process hen egg-white lysozymeShingo Kato, Nobuo Shimamoto, Hiroyasu UtiyamaCite this: Biochemistry 1982, 21, 1, 38–43Publication Date (Print):January 5, 1982Publication History Published online1 May 2002Published inissue 5 January 1982https://doi.org/10.1021/bi00530a007RIGHTS & PERMISSIONSArticle Views138Altmetric-Citations54LEARN ABOUT THESE METRICSArticle Views are COUNTER-compliant sum...

To elucidate the mechanism of u release in transcript by Escherichia coli DNA-dependent RNA polymerase, we obtained time courses and elongation product a rapid kinetic technique; transcription was synchronously initiated from A I promoter on T7 DNA addition four substrates to stoichiometric mixture holoenzyme template DNA, then quenched EDTA.The rate changed limiting concentration one substrates, GTP.At reduced GTP concentration, decelerated, but course unchanged.No connection between length...

In transcription initiation, all RNA polymerase molecules bound to a promoter have been conventionally supposed proceed into elongation of transcript. However, for Escherichia coli polymerase, evidence has accumulated view that only its fraction can and the rest is retained at in non-productive form: pathway branching initiation. Proteins such as GreA GreB affect these fractions several promoters vitro. To reveal ubiquitous existence branched mechanism E. coli, we searched candidate genes...

The single-stranded DNA (ssDNA) binding protein from Escherichia coli CEcoSSB) plays a central role in replication, recombination, and repair. tertiary structure of EcoSSB was determined at 2.2 Å resolution. This is rather higher resolution than previously reported. Crystals were grown the homogeneous intact but tetramer crystals contains truncated subunits lacking part C-ter-minal. includes biologically important flexible loops C-terminal regions, revealed existence concavities. These...

Gene A of the phi X174 genome codes for two proteins, and A* (Linney, E.A., Hayashi, M.N. (1973) Nature New Biol. 245, 6-8) molecular weights 60,000 35,000, respectively. The X protein is formed from a natural internal initiator site within gene cistron while product entire gene. These proteins have been purified to homogeneity as judged by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Previous studies shown that an endonuclease which specifically introduces discontinuity in...

ABSTRACT In growing bacterial cells, the global reorganization of transcription is associated with alterations RNA polymerase composition and superhelical density DNA. However, existence any regulatory device coordinating these changes remains elusive. Here we show that in an exponentially Escherichia coli rpoZ mutant lacking ω subunit, impact Eσ 38 holoenzyme on enhanced parallel overall DNA relaxation. Conversely, overproduction σ 70 increases both supercoiling genes utilizing high...

Highly purified Escherichia coli RNA polymerase contains a small subunit termed ω that has molecular mass of 10 105 Da and is comprised 91 amino acids. E. strains lacking (ω‐less) are viable, but exhibit slow‐growth phenotype. Renaturation isolated from an ω‐less mutant, in the presence ω, resulted maximum recovery activity. The recruits chaperonin, GroEL (unlike wild‐type enzyme), suggesting structural deformity mutant enzyme. GroEL‐containing core interacts efficiently with σ 70 to...

Many proteins select special DNA sequences to form functional complexes. In one possible mechanism, protein molecules would scan by tracking a groove without complete dissociation. Upon dragging single of over surface carrying fixed Escherichia coli RNA polymerase holoenzyme, we detected rotation individual molecules, providing direct evidence that DNA-binding can track groove. These results confirm our previous observations longitudinal movement along fixed, extended and, moreover, imply...

Ribosomal proteins S10 and S2 were each fused with GFP to track the fates of these in stationary growth phase following decay period Escherichia coli . The localized mainly cytoplasm, their amounts proportional colony‐forming unit. S10‐GFP strains that lacked genes responsible for regulating 100S ribosomes S2‐GFP strain was unable form both showed shortened phases. This result indicates exhibit earlier death absence formation (S2‐GFP, ∆rmf ∆hpf ) breakdown (S10‐GFP ∆yfiA ). Therefore,...