Spectrum of a Pot for DNA Complexes

Torus Circumference and Thickness Parameters From a Linear DNA Size Series Suggest How Toruses Self-Assemble

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100119430 ◽

1985 ◽

Vol 43 ◽

pp. 522-523

Author(s):

George C. Ruben ◽

Kenneth A. Marx

Keyword(s):

Tertiary Structure ◽

Dna Complexes ◽

Tertiary Structures ◽

Self Assembling ◽

Double Stranded Dna ◽

Calf Thymus ◽

Dna Organization ◽

Condensed Dna ◽

Dna Size

Certain double stranded DNA bacteriophage and viruses are thought to have their DNA organized into large torus shaped structures. Morphologically, these poorly understood biological DNA tertiary structures resemble spermidine-condensed DNA complexes formed in vitro in the total absence of other macromolecules normally synthesized by the pathogens for the purpose of their own DNA packaging. Therefore, we have studied the tertiary structure of these self-assembling torus shaped spermidine- DNA complexes in a series of reports. Using freeze-etch, low Pt-C metal (10-15Å) replicas, we have visualized the microscopic DNA organization of both calf Thymus( CT) and linear 0X-174 RFII DNA toruses. In these structures DNA is circumferentially wound, continuously, around the torus into a semi-crystalline, hexagonal packed array of parallel DNA helix sections.

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Biochemical Chgaracterization of Recombinant Baculovirus 373 K/E p53 Protein

International Journal of Contemporary Research and Review ◽

10.15520/ijcrr/2018/9/03/479 ◽

2018 ◽

Vol 9 (03) ◽

pp. 20204-20223

Author(s):

Maghsoudi, Hossein ◽

U Pati

Keyword(s):

Dna Binding ◽

P53 Protein ◽

Expression System ◽

Gel Filtration ◽

Recombinant Baculovirus ◽

Baculovirus Expression System ◽

Cross Linking ◽

Mobility Shift ◽

Dna Complexes ◽

P53 Antibodies

In this study, we expressed and purified the recombinant baculovirus 373 K/E p53 protein in a baculovirus expression system to characterize this mutant and compare it with wild type p53. Gel- filtration chromatography and chemical cross-linking experiments indicated that purified recombinant baculovirus 373 K/E p53 protein assembles into multimeric forms ranging from tetramers to polymers. Gel-mobility shift assays and protein-DNA cross-linking studies demonstrated that the recombinant protein binds, to a consensus DNA target as a dimer but that additional p53 mutant molecules may then associate with the preformed p53-dimer-DNA complexes to form a larger p53_DNA complexes. These observations suggest that the p53 mutant tetramers and polymers that forms the minimal p53 mutant complex in solution dissociated upon DNA binding to form p53 mutant dimmer DNA complexes. The DNA binding activity of this mutant was then investigated using electrophoretic mobility shift assays as well as supershift assay with anti-p53 antibodies. Binding of the anti-p53 antibody PAb421to the oligomerization promoting domain on p53 stimulated the sequential formation of both the p53_dimer DNA and larger p53-DNA complexes

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