In genetics, complementary DNA (cDNA) is DNA that was reverse transcribed from an RNA. cDNA exists in both single-stranded and double-stranded forms and in both natural and engineered forms.
A plasmid is a small, extrachromosomal DNA molecule within a cell that is physically separated from chromosomal DNA and can replicate independently. They are most commonly found as small circular, double-stranded DNA molecules in bacteria; however, plasmids are sometimes present in archaea and eukaryotic organisms. In nature, plasmids often carry genes that benefit the survival of the organism and confer selective advantage such as antibiotic resistance. While chromosomes are large and contain all the essential genetic information for living under normal conditions, plasmids are usually very small and contain only additional genes that may be useful in certain situations or conditions. Artificial plasmids are widely used as vectors in molecular cloning, serving to drive the replication of recombinant DNA sequences within host organisms. In the laboratory, plasmids may be introduced into a cell via transformation. Synthetic plasmids are available for procurement over the internet.
An expression vector, otherwise known as an expression construct, is usually a plasmid or virus designed for gene expression in cells. The vector is used to introduce a specific gene into a target cell, and can commandeer the cell's mechanism for protein synthesis to produce the protein encoded by the gene. Expression vectors are the basic tools in biotechnology for the production of proteins.
In molecular biology, a library is a collection of genetic material fragments that are stored and propagated in a population of microbes through the process of molecular cloning. There are different types of DNA libraries, including cDNA libraries, genomic libraries and randomized mutant libraries. DNA library technology is a mainstay of current molecular biology, genetic engineering, and protein engineering, and the applications of these libraries depend on the source of the original DNA fragments. There are differences in the cloning vectors and techniques used in library preparation, but in general each DNA fragment is uniquely inserted into a cloning vector and the pool of recombinant DNA molecules is then transferred into a population of bacteria or yeast such that each organism contains on average one construct. As the population of organisms is grown in culture, the DNA molecules contained within them are copied and propagated.
Synthetic biology (SynBio) is a multidisciplinary field of science that focuses on living systems and organisms, and it applies engineering principles to develop new biological parts, devices, and systems or to redesign existing systems found in nature.
Recombinant DNA (rDNA) molecules are DNA molecules formed by laboratory methods of genetic recombination that bring together genetic material from multiple sources, creating sequences that would not otherwise be found in the genome.
A DNA construct is an artificially-designed segment of DNA borne on a vector that can be used to incorporate genetic material into a target tissue or cell. A DNA construct contains a DNA insert, called a transgene, delivered via a transformation vector which allows the insert sequence to be replicated and/or expressed in the target cell. This gene can be cloned from a naturally occurring gene, or synthetically constructed. The vector can be delivered using physical, chemical or viral methods. Typically, the vectors used in DNA constructs contain an origin of replication, a multiple cloning site, and a selectable marker. Certain vectors can carry additional regulatory elements based on the expression system involved.
This page provides an alphabetical list of articles and other pages about biotechnology.
Steven Albert Benner is an American chemist. He has been a professor at Harvard University, ETH Zurich, and most recently at the University of Florida, where he was the V.T. & Louise Jackson Distinguished Professor of Chemistry. In 2005, he founded The Westheimer Institute of Science and Technology (TWIST) and the Foundation For Applied Molecular Evolution. Benner has also founded the companies EraGen Biosciences and Firebird BioMolecular Sciences LLC.
DNA shuffling, also known as molecular breeding, is an in vitro random recombination method to generate mutant genes for directed evolution and to enable a rapid increase in DNA library size. Three procedures for accomplishing DNA shuffling are molecular breeding which relies on homologous recombination or the similarity of the DNA sequences, restriction enzymes which rely on common restriction sites, and nonhomologous random recombination which requires the use of hairpins. In all of these techniques, the parent genes are fragmented and then recombined.
Gene delivery is the process of introducing foreign genetic material, such as DNA or RNA, into host cells. Gene delivery must reach the genome of the host cell to induce gene expression. Successful gene delivery requires the foreign gene delivery to remain stable within the host cell and can either integrate into the genome or replicate independently of it. This requires foreign DNA to be synthesized as part of a vector, which is designed to enter the desired host cell and deliver the transgene to that cell's genome. Vectors utilized as the method for gene delivery can be divided into two categories, recombinant viruses and synthetic vectors.
Synthetic genomics is a nascent field of synthetic biology that uses aspects of genetic modification on pre-existing life forms, or artificial gene synthesis to create new DNA or entire lifeforms.
Artificial gene synthesis, or simply gene synthesis, refers to a group of methods that are used in synthetic biology to construct and assemble genes from nucleotides de novo. Unlike DNA synthesis in living cells, artificial gene synthesis does not require template DNA, allowing virtually any DNA sequence to be synthesized in the laboratory. It comprises two main steps, the first of which is solid-phase DNA synthesis, sometimes known as DNA printing. This produces oligonucleotide fragments that are generally under 200 base pairs. The second step then involves connecting these oligonucleotide fragments using various DNA assembly methods. Because artificial gene synthesis does not require template DNA, it is theoretically possible to make a completely synthetic DNA molecule with no limits on the nucleotide sequence or size.
Christopher Voigt is an American synthetic biologist, molecular biophysicist, and engineer.
Gene Designer is a computer software package for bioinformatics. It is used by molecular biologists from academia, government, and the pharmaceutical, chemical, agricultural, and biotechnology industries to design, clone, and validate genetic sequences. It is proprietary software, released as freeware needing registration.
Molecular cloning is a set of experimental methods in molecular biology that are used to assemble recombinant DNA molecules and to direct their replication within host organisms. The use of the word cloning refers to the fact that the method involves the replication of one molecule to produce a population of cells with identical DNA molecules. Molecular cloning generally uses DNA sequences from two different organisms: the species that is the source of the DNA to be cloned, and the species that will serve as the living host for replication of the recombinant DNA. Molecular cloning methods are central to many contemporary areas of modern biology and medicine.
Synthetic biological circuits are an application of synthetic biology where biological parts inside a cell are designed to perform logical functions mimicking those observed in electronic circuits. Typically, these circuits are categorized as either genetic circuits, RNA circuits, or protein circuits, depending on the types of biomolecule that interact to create the circuit's behavior. The applications of all three types of circuit range from simply inducing production to adding a measurable element, like green fluorescent protein, to an existing natural biological circuit, to implementing completely new systems of many parts.
Genetic engineering techniques allow the modification of animal and plant genomes. Techniques have been devised to insert, delete, and modify DNA at multiple levels, ranging from a specific base pair in a specific gene to entire genes. There are a number of steps that are followed before a genetically modified organism (GMO) is created. Genetic engineers must first choose what gene they wish to insert, modify, or delete. The gene must then be isolated and incorporated, along with other genetic elements, into a suitable vector. This vector is then used to insert the gene into the host genome, creating a transgenic or edited organism.
Infologs are independently designed synthetic genes derived from one or a few genes where substitutions are systematically incorporated to maximize information. Infologs are designed for perfect diversity distribution to maximize search efficiency.
Transient expression, more frequently referred to "transient gene expression", is the temporary expression of genes that are expressed for a short time after nucleic acid, most frequently plasmid DNA encoding an expression cassette, has been introduced into eukaryotic cells with a chemical delivery agent like calcium phosphate (CaPi) or polyethyleneimine (PEI). However, unlike "stable expression," the foreign DNA does not fuse with the host cell DNA, resulting in the inevitable loss of the vector after several cell replication cycles. The majority of transient gene expressions are done with cultivated animal cells. The technique is also used in plant cells; however, the transfer of nucleic acids into these cells requires different methods than those with animal cells. In both plants and animals, transient expression should result in a time-limited use of transferred nucleic acids, since any long-term expression would be called "stable expression."
