Biomaterial Database

Rapid purification of Ti plasmids from Agrobacterium by ethidium bromide treatment and phenol extraction. 1993

L Zhang, and A Kerr

Waite Agricultural Research Institute, University of Adelaide, Glen Osmond, SA, Australia.

An efficient method is described for the purification of Ti plasmid DNA from Agrobacterium. The procedure is based on the relative binding capacity of ethidium bromide to supercoiled plasmid DNA and linear DNA and on the high solubility of ethidium bromide in phenol. Following treatment with ethidium bromide, more than 87% of linear chromosomal DNA and most of the RNA was present in the phenol phase, while 91% of Ti plasmid DNA was recovered from the aqueous phase. The Ti plasmid DNA was sufficiently pure for restriction endonuclease analysis and cloning. The procedure is simple, fast and provides eight times higher yield than the standard isopycnic ultracentrifugation method.

UI	MeSH Term	Description	Entries
D010636	Phenols	Benzene derivatives that include one or more hydroxyl groups attached to the ring structure.
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
D012150	Polymorphism, Restriction Fragment Length	Variation occurring within a species in the presence or length of DNA fragment generated by a specific endonuclease at a specific site in the genome. Such variations are generated by mutations that create or abolish recognition sites for these enzymes or change the length of the fragment.	RFLP,Restriction Fragment Length Polymorphism,RFLPs,Restriction Fragment Length Polymorphisms
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
D004269	DNA, Bacterial	Deoxyribonucleic acid that makes up the genetic material of bacteria.	Bacterial DNA
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
D004996	Ethidium	A trypanocidal agent and possible antiviral agent that is widely used in experimental cell biology and biochemistry. Ethidium has several experimentally useful properties including binding to nucleic acids, noncompetitive inhibition of nicotinic acetylcholine receptors, and fluorescence among others. It is most commonly used as the bromide.	Ethidium Bromide,Homidium Bromide,Novidium,Bromide, Ethidium,Bromide, Homidium
D012995	Solubility	The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Solubilities
D016960	Agrobacterium tumefaciens	A species of gram-negative, aerobic bacteria isolated from soil and the stems, leafs, and roots of plants. Some biotypes are pathogenic and cause the formation of PLANT TUMORS in a wide variety of higher plants. The species is a major research tool in biotechnology.	Alcaligenes radiobacter,Bacillus radiobacter,Bacterium radiobacter,Bacterium tumefaciens,Phytomonas tumefaciens,Polymonas tumefaciens,Pseudomonas radiobacter,Pseudomonas tumefaciens,Rhizobium radiobacter,Agrobacterium radiobacter