Biomaterial Database

An autonomously replicating plasmid transforms Aspergillus nidulans at high frequency. 1991

D Gems, and I L Johnstone, and A J Clutterbuck

Institute of Genetics, University of Glasgow, Scotland, U.K.

From an unstable Aspergillus nidulans colony, resulting from transformation with an A. nidulans gene bank, a plasmid was reisolated which transformed A. nidulans at a frequency of 20,000 transformants per 10(6) protoplasts at near saturation levels of transforming DNA. This represents a 250-fold enhancement of transformation efficiency over that found for typical integrative vectors such as pILJ16, the plasmid used in gene bank constructions. The plasmid, designated ARp1, is 11.5 kb in size, and consists of sequences derived from the 5.4-kb gene bank vector pILJ16, which carries the A. nidulans gene argB, and a 6.1-kb insert, designated AMA1. Southern analysis of transformant DNA showed ARp1 to be maintained in free form and not integrated into the chromosome. It has a mean copy number of 10-30 per haploid genome, and is mitotically unstable, being lost from 65% of asexual progeny of transformants. It shows similar transformational properties in A. niger and A. oryzae.

UI	MeSH Term	Description	Entries
D008040	Genetic Linkage	The co-inheritance of two or more non-allelic GENES due to their being located more or less closely on the same CHROMOSOME.	Genetic Linkage Analysis,Linkage, Genetic,Analyses, Genetic Linkage,Analysis, Genetic Linkage,Genetic Linkage Analyses,Linkage Analyses, Genetic,Linkage Analysis, Genetic
D010641	Phenotype	The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.	Phenotypes
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
D012093	Replicon	Any DNA sequence capable of independent replication or a molecule that possesses a REPLICATION ORIGIN and which is therefore potentially capable of being replicated in a suitable cell. (Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Replication Unit,Replication Units,Replicons,Unit, Replication,Units, Replication
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
D003001	Cloning, Molecular	The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.	Molecular Cloning
D004261	DNA Replication	The process by which a DNA molecule is duplicated.	Autonomous Replication,Replication, Autonomous,Autonomous Replications,DNA Replications,Replication, DNA,Replications, Autonomous,Replications, DNA
D004271	DNA, Fungal	Deoxyribonucleic acid that makes up the genetic material of fungi.	Fungal DNA
D005819	Genetic Markers	A phenotypically recognizable genetic trait which can be used to identify a genetic locus, a linkage group, or a recombination event.	Chromosome Markers,DNA Markers,Markers, DNA,Markers, Genetic,Genetic Marker,Marker, Genetic,Chromosome Marker,DNA Marker,Marker, Chromosome,Marker, DNA,Markers, Chromosome
D001233	Aspergillus nidulans	A species of imperfect fungi from which the antibiotic nidulin is obtained. Its teleomorph is Emericella nidulans.	Aspergillus nidulellus,Emericella nidulans