from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A circular, double-stranded unit of DNA that replicates within a cell independently of the chromosomal DNA. Plasmids are most often found in bacteria and are used in recombinant DNA research to transfer genes between cells.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A circle of double-stranded DNA that is separate from the chromosomes, and which is found in bacteria and protozoa.
from the GNU version of the Collaborative International Dictionary of English
- n. A piece of DNA, usually circular, functioning as part of the genetic material of a cell, not integrated with the chromosome and replicating independently of the chromosome, but transferred, like the chromosome, to subsequent generations of daughter cells. In bacteria, plasmids often carry the genes for antibiotic resistance; they are exploited in genetic engineering as the vehicles for introduction of extraneous DNA into cells, to alter the genetic makeup of the cell. The cells thus altered may produce desirable proteins which are extracted and used; in the case of genetically altered plant cells, the altered cells may grow into complete plants with changed properties, as for example, increased resistance to disease.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a small cellular inclusion consisting of a ring of DNA that is not in a chromosome but is capable of autonomous replication
This plasmid is optimal for nonmammalian expression. pDsRed1-1: This plasmid contains an RFP gene that has been altered for human expression of RFP (DsRed1).
Co-transfection of human TLR2 with increasing amounts of the expression plasmid encoding alphaT2ib into HEK293 cells demonstrated high efficiency of the TLR2-alphaT2ib interaction.
This conclusion was further supported by the fact that large part of the secretome was found to be coded by a piece of extra-chromosomal DNA called plasmid, which is, simply, the most mobile part of the whole bacterial genome
That vehicle (often a subcellular structure called a plasmid) is then inserted into a different cell, which activates the gene, leading to the production of a scientifically or commercially useful protein.
Yersinia pestis in the 109 samples from the cemetery in East Smithfield, his lab employed a sort of sensitive fishing technique, using tiny segments of DNA that matched up with segments from a ring of DNA, called a plasmid, found in the bacterium.
Pps were produced by transfecting 293T cells with four plasmids: an HA expression plasmid, an NA expression plasmid, a Gag-pol-encoding plasmid, and a reporter plasmid.
"It's a type of resistance that's carried on a mobile piece of DNA called a plasmid, and it's able very quickly to transfer from bacteria to bacteria," said Walsh.
The sorted cells were then subjected to limiting dilution to obtain pure clones of double-positive cells, followed by electroporation of a Flp-expression plasmid to achieve a clean translocation.
Artificial miRNAs (amiRNAs) expression plasmid vectors such as pre-miRNA 155-designed shRNAs vectors
Sp-1 transcription factor activates transcription from resistin gene promoter. 1 million HEK cells were transfected with 1 µg of pGLHres 0.34 k (Bar1) or pGLHres 0.34 k Sp-1mut either alone (Fig B Bar2) or with Sp-1 over expression plasmid (Bar 3) as described.