Biomaterial Database

Microscopic analysis of DNA and DNA-protein assembly by transmission electron microscopy, scanning tunneling microscopy and scanning force microscopy. 1996

T Müller-Reichert, and H Gross

European Molecular Biology Laboratory, Heidelberg, Germany. reichert@embl-heidelberg.de

To investigate DNA and DNA-protein assembly, nucleic acids were adsorbed to freshly cleaved mica in the presence of magnesium ions. The efficiency of DNA adhesion and the distribution of the molecules on the mica surface were checked by transmission electron microscopy. In addition, various kinds of DNA-protein interactions including DNA wrapping and DNA supercoiling were analyzed using electron microscopy. In parallel, this Mg2+/mica method can be applied (1) to analyze embedded DNA by scanning tunneling microscopy, (2) to visualize freeze-dried, metal coated DNA-protein complexes by tunneling microscopy, and (3) to image DNA or DNA-protein interaction in air or in liquid by scanning force microscopy. An advantage of such a correlative approach is that parallel imaging can reveal complementary information. The benefit of such a combined approach in analysis of protein-induced DNA bending is discussed.

UI	MeSH Term	Description	Entries
D008274	Magnesium	A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D009690	Nucleic Acid Conformation	The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.	DNA Conformation,RNA Conformation,Conformation, DNA,Conformation, Nucleic Acid,Conformation, RNA,Conformations, DNA,Conformations, Nucleic Acid,Conformations, RNA,DNA Conformations,Nucleic Acid Conformations,RNA Conformations
D004247	DNA	A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).	DNA, Double-Stranded,Deoxyribonucleic Acid,ds-DNA,DNA, Double Stranded,Double-Stranded DNA,ds DNA
D004268	DNA-Binding Proteins	Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.	DNA Helix Destabilizing Proteins,DNA-Binding Protein,Single-Stranded DNA Binding Proteins,DNA Binding Protein,DNA Single-Stranded Binding Protein,SS DNA BP,Single-Stranded DNA-Binding Protein,Binding Protein, DNA,DNA Binding Proteins,DNA Single Stranded Binding Protein,DNA-Binding Protein, Single-Stranded,Protein, DNA-Binding,Single Stranded DNA Binding Protein,Single Stranded DNA Binding Proteins
D000538	Aluminum Silicates	Any of the numerous types of clay which contain varying proportions of Al2O3 and SiO2. They are made synthetically by heating aluminum fluoride at 1000-2000 degrees C with silica and water vapor. (From Hawley's Condensed Chemical Dictionary, 11th ed)	Aluminum Silicate,Silicate, Aluminum,Silicates, Aluminum
D016252	Microscopy, Scanning Tunneling	A type of scanning probe microscopy in which a very sharp conducting needle is swept just a few angstroms above the surface of a sample. The tiny tunneling current that flows between the sample and the needle tip is measured, and from this are produced three-dimensional topographs. Due to the poor electron conductivity of most biological samples, thin metal coatings are deposited on the sample.	Scanning Tunneling Microscopy,Scanning Tunnelling Microscopy,Microscopies, Scanning Tunneling,Microscopies, Scanning Tunnelling,Microscopy, Scanning Tunnelling,Scanning Tunneling Microscopies,Scanning Tunnelling Microscopies,Tunneling Microscopies, Scanning,Tunneling Microscopy, Scanning,Tunnelling Microscopies, Scanning,Tunnelling Microscopy, Scanning
D016591	Histocytological Preparation Techniques	Methods of preparing cells or tissues for examination and study of their origin, structure, function, or pathology. The methods include preservation, fixation, sectioning, staining, replica, or other technique to allow for viewing using a microscope.	Cytohistological Preparation Techniques,Cytohistologic Preparation Technics,Cytohistologic Preparation Technique,Cytohistologic Preparation Techniques,Cytohistological Preparation Technic,Cytohistological Preparation Technics,Cytohistological Preparation Technique,Histocytologic Preparation Technic,Histocytologic Preparation Technics,Histocytologic Preparation Technique,Histocytologic Preparation Techniques,Histocytological Preparation Technic,Histocytological Preparation Technics,Histocytological Preparation Technique,Preparation Technic, Cytohistologic,Preparation Technic, Cytohistological,Preparation Technic, Histocytologic,Preparation Technic, Histocytological,Preparation Technics, Cytohistologic,Preparation Technics, Cytohistological,Preparation Technics, Histocytologic,Preparation Technics, Histocytological,Preparation Technique, Cytohistologic,Preparation Technique, Cytohistological,Preparation Technique, Histocytologic,Preparation Technique, Histocytological,Preparation Techniques, Cytohistologic,Preparation Techniques, Cytohistological,Preparation Techniques, Histocytologic,Preparation Techniques, Histocytological,Technic, Cytohistologic Preparation,Technic, Cytohistological Preparation,Technic, Histocytologic Preparation,Technic, Histocytological Preparation,Technics, Cytohistologic Preparation,Technics, Cytohistological Preparation,Technics, Histocytologic Preparation,Technics, Histocytological Preparation,Technique, Cytohistologic Preparation,Technique, Cytohistological Preparation,Technique, Histocytologic Preparation,Technique, Histocytological Preparation,Techniques, Cytohistologic Preparation,Techniques, Cytohistological Preparation,Techniques, Histocytologic Preparation,Techniques, Histocytological Preparation,Cytohistologic Preparation Technic
D018625	Microscopy, Atomic Force	A type of scanning probe microscopy in which a probe systematically rides across the surface of a sample being scanned in a raster pattern. The vertical position is recorded as a spring attached to the probe rises and falls in response to peaks and valleys on the surface. These deflections produce a topographic map of the sample.	Atomic Force Microscopy,Force Microscopy,Scanning Force Microscopy,Atomic Force Microscopies,Force Microscopies,Force Microscopies, Scanning,Force Microscopy, Scanning,Microscopies, Atomic Force,Microscopies, Force,Microscopies, Scanning Force,Microscopy, Force,Microscopy, Scanning Force,Scanning Force Microscopies