Biomaterial Database

The isolation of mouse hepatocyte gap junctions. Preliminary chemical characterization and x-ray diffraction. 1972

D A Goodenough, and W Stoeckenius

A method is reported for isolating a preparation of hepatic gap junctions from the mouse. The method involves a collagenase digestion, treatment with the detergent Sarkosyl NL-97, and ultrasonication, followed by sucrose gradient ultracentrifugation. A run with 36 animals yields 0.1-0.5 mg protein. Electron microscopy with thin-sectioning and negative staining techniques reveals that the final pellet is a very pure preparation of gap junctions, accompanied by a small amount of amorphous contamination. Polyacrylamide-gel electrophoresis of sodium dodecyl sulfate (SDS)-solubilized material shows one major protein in the junction, with an apparent mol wt of 20,000, and two minor components. Thin-layer chromatography demonstrates one major and one minor phospholipid, and some neutral lipid. Low-angle X-ray diffraction of wet and dried specimens show reflections which index on an 86 A center-to-center hexagonal lattice, corresponding closely to electron microscope data. Dried specimens also show a lamellar diffraction, corresponding to the total profile thickness of the junction (150 A).

UI	MeSH Term	Description	Entries
D007365	Intercellular Junctions	Direct contact of a cell with a neighboring cell. Most such junctions are too small to be resolved by light microscopy, but they can be visualized by conventional or freeze-fracture electron microscopy, both of which show that the interacting CELL MEMBRANE and often the underlying CYTOPLASM and the intervening EXTRACELLULAR SPACE are highly specialized in these regions. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p792)	Cell Junctions,Cell Junction,Intercellular Junction,Junction, Cell,Junction, Intercellular,Junctions, Cell,Junctions, Intercellular
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D002499	Centrifugation, Density Gradient	Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Centrifugations, Density Gradient,Density Gradient Centrifugation,Density Gradient Centrifugations,Gradient Centrifugation, Density,Gradient Centrifugations, Density
D002855	Chromatography, Thin Layer	Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Chromatography, Thin-Layer,Thin Layer Chromatography,Chromatographies, Thin Layer,Chromatographies, Thin-Layer,Thin Layer Chromatographies,Thin-Layer Chromatographies,Thin-Layer Chromatography
D003012	Microbial Collagenase	A metalloproteinase which degrades helical regions of native collagen to small fragments. Preferred cleavage is -Gly in the sequence -Pro-Xaa-Gly-Pro-. Six forms (or 2 classes) have been isolated from Clostridium histolyticum that are immunologically cross-reactive but possess different sequences and different specificities. Other variants have been isolated from Bacillus cereus, Empedobacter collagenolyticum, Pseudomonas marinoglutinosa, and species of Vibrio and Streptomyces. EC 3.4.24.3.	Clostridiopeptidase A,Clostridium histolyticum Collagenase,Collagenase, Microbial,Collagenase Clostridium histolyticum,Collagenase-Like Peptidase,Collalysine,Nucleolysin,Clostridium histolyticum, Collagenase,Collagenase Like Peptidase,Collagenase, Clostridium histolyticum,Peptidase, Collagenase-Like,histolyticum, Collagenase Clostridium
D003720	Densitometry	The measurement of the density of a material by measuring the amount of light or radiation passing through (or absorbed by) the material.	Densitometries
D003902	Detergents	Purifying or cleansing agents, usually salts of long-chain aliphatic bases or acids, that exert cleansing (oil-dissolving) and antimicrobial effects through a surface action that depends on possessing both hydrophilic and hydrophobic properties.	Cleansing Agents,Detergent Pods,Laundry Detergent Pods,Laundry Pods,Syndet,Synthetic Detergent,Agent, Cleansing,Agents, Cleansing,Cleansing Agent,Detergent,Detergent Pod,Detergent Pod, Laundry,Detergent Pods, Laundry,Detergent, Synthetic,Detergents, Synthetic,Laundry Detergent Pod,Laundry Pod,Pod, Detergent,Pod, Laundry,Pod, Laundry Detergent,Pods, Detergent,Pods, Laundry,Pods, Laundry Detergent,Synthetic Detergents
D004589	Electrophoresis, Disc	Electrophoresis in which discontinuities in both the voltage and pH gradients are introduced by using buffers of different composition and pH in the different parts of the gel column. The term 'disc' was originally used as an abbreviation for 'discontinuous' referring to the buffers employed, and does not have anything to do with the shape of the separated zones.	Electrophoresis, Disk,Disc Electrophoresis,Disk Electrophoresis
D005613	Freeze Etching	A replica technique in which cells are frozen to a very low temperature and cracked with a knife blade to expose the interior surfaces of the cells or cell membranes. The cracked cell surfaces are then freeze-dried to expose their constituents. The surfaces are now ready for shadowing to be viewed using an electron microscope. This method differs from freeze-fracturing in that no cryoprotectant is used and, thus, allows for the sublimation of water during the freeze-drying process to etch the surfaces.	Etching, Freeze
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia