Biomaterial Database

High-resolution capillary electrophoretic separation of supercoiled plasmid DNAs and their conformers in dilute hydroxypropylmethyl cellulose solutions containing no intercalating agent. 1998

D T Mao, and J D Levin, and L Yu, and R M Lautamo

J&W Scientific, Folsom, CA 95630, USA.

The three conformers of plasmid pBR322, linear, supercoiled and nicked circular forms, were separated by capillary electrophoresis (CE) in 0.1% hydroxypropylmethyl cellulose (HPMC) solution in the absence of intercalating agents and the migration order was confirmed by co-migration of enzymatically prepared corresponding DNAs. The previously observed broad peaks of supercoiled DNAs in CE are results of unresolved peaks of topoisomers which differ only in the degrees of twisting. We have demonstrated the separation of an artificial topoisomer ladder made from pBR322 and topoisomerase I. The population of topoisomers of a supercoiled DNA is dependent on sample matrices and separation conditions.

UI	MeSH Term	Description	Entries
D008747	Methylcellulose	Methylester of cellulose. Methylcellulose is used as an emulsifying and suspending agent in cosmetics, pharmaceutics and the chemical industry. It is used therapeutically as a bulk laxative.	BFL,Celevac,Cellothyl,Cellulone,Citrucel,Cologel,Dacryolarmes,Methocel,Methyl Cellulose,Muciplasma,Cellulose, Methyl
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
D010957	Plasmids	Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.	Episomes,Episome,Plasmid
D004264	DNA Topoisomerases, Type I	DNA TOPOISOMERASES that catalyze ATP-independent breakage of one of the two strands of DNA, passage of the unbroken strand through the break, and rejoining of the broken strand. DNA Topoisomerases, Type I enzymes reduce the topological stress in the DNA structure by relaxing the superhelical turns and knotted rings in the DNA helix.	DNA Nicking-Closing Protein,DNA Relaxing Enzyme,DNA Relaxing Protein,DNA Topoisomerase,DNA Topoisomerase I,DNA Topoisomerase III,DNA Topoisomerase III alpha,DNA Topoisomerase III beta,DNA Untwisting Enzyme,DNA Untwisting Protein,TOP3 Topoisomerase,TOP3alpha,TOPO IIIalpha,Topo III,Topoisomerase III,Topoisomerase III beta,Topoisomerase IIIalpha,Topoisomerase IIIbeta,DNA Nicking-Closing Proteins,DNA Relaxing Enzymes,DNA Type 1 Topoisomerase,DNA Untwisting Enzymes,DNA Untwisting Proteins,Topoisomerase I,Type I DNA Topoisomerase,III beta, Topoisomerase,III, DNA Topoisomerase,III, Topo,III, Topoisomerase,IIIalpha, TOPO,IIIalpha, Topoisomerase,IIIbeta, Topoisomerase,Topoisomerase III, DNA,Topoisomerase, TOP3,beta, Topoisomerase III
D004270	DNA, Circular	Any of the covalently closed DNA molecules found in bacteria, many viruses, mitochondria, plastids, and plasmids. Small, polydisperse circular DNA's have also been observed in a number of eukaryotic organisms and are suggested to have homology with chromosomal DNA and the capacity to be inserted into, and excised from, chromosomal DNA. It is a fragment of DNA formed by a process of looping out and deletion, containing a constant region of the mu heavy chain and the 3'-part of the mu switch region. Circular DNA is a normal product of rearrangement among gene segments encoding the variable regions of immunoglobulin light and heavy chains, as well as the T-cell receptor. (Riger et al., Glossary of Genetics, 5th ed & Segen, Dictionary of Modern Medicine, 1992)	Circular DNA,Circular DNAs,DNAs, Circular
D004278	DNA, Superhelical	Circular duplex DNA isolated from viruses, bacteria and mitochondria in supercoiled or supertwisted form. This superhelical DNA is endowed with free energy. During transcription, the magnitude of RNA initiation is proportional to the DNA superhelicity.	DNA, Supercoiled,DNA, Supertwisted,Supercoiled DNA,Superhelical DNA,Supertwisted DNA
D012996	Solutions	The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)	Solution
D019075	Electrophoresis, Capillary	A highly-sensitive (in the picomolar range, which is 10,000-fold more sensitive than conventional electrophoresis) and efficient technique that allows separation of PROTEINS; NUCLEIC ACIDS; and CARBOHYDRATES. (Segen, Dictionary of Modern Medicine, 1992)	Capillary Zone Electrophoresis,Capillary Electrophoreses,Capillary Electrophoresis,Capillary Zone Electrophoreses,Electrophoreses, Capillary,Electrophoreses, Capillary Zone,Electrophoresis, Capillary Zone,Zone Electrophoreses, Capillary,Zone Electrophoresis, Capillary
D065347	Hypromellose Derivatives	Polymeric compounds that contain repeating units of hydroxypropyl methylcellulose. The properties of hypromellose polymers can vary greatly and are defined by their molecular weight, the percentage of hydroxyl groups, the percentage of hydroxypropyl groups, and viscosity measurements. They are found a broad variety of commercial products such as FOOD ADDITIVES; EXCIPIENTS; and LUBRICANTS.	HPMC 2910,HPMC-K-100 M,Hydroxypropyl Methylcellulose,Hydroxypropylmethylcellulose,Hypromellose,K-8515,K8515,MHPC Polymer,Methocel E,Methoxyhydroxypropylcellulose,Methyl Hydroxypropyl Cellulose,Methyl-hydroxypropyl-cellulose,Derivative, Hypromellose,Derivatives, Hypromellose,HPMC K 100 M,HPMCK100 M,Hypromellose Derivative,K 8515