Recombination (cosmology): In cosmology, recombination refers to the epoch at which charged electrons and protons first became bound to form electrically neutral hydrogen atoms.Note that the term recombination is a misnomer, considering that it represents the first time that electrically neutral hydrogen formed.Symmetry element: A symmetry element is a point of reference about which symmetry operations can take place. In particular, symmetry elements can be centers of inversion, axes of rotation and mirror planes.Coles PhillipsConditional gene knockout: ==Conditional gene knockout==Base excision repair: frame|right|Basic steps of base excision repair|Basic steps of base excision repairSilent mutation: Silent mutations are mutations in DNA that do not significantly alter the phenotype of the organism in which they occur. Silent mutations can occur in non-coding regions (outside of genes or within introns), or they may occur within exons.Site-specific recombination: Site-specific recombination, also known as conservative site-specific recombination, is a type of genetic recombination in which DNA strand exchange takes place between segments possessing only a limited degree of sequence homology. Site-specific recombinases (SSRs) perform rearrangements of DNA segments by recognizing and binding to short DNA sequences (sites), at which they cleave the DNA backbone, exchange the two DNA helices involved and rejoin the DNA strands.Hin recombinase: Hin recombinase is a 21kD protein composed of 198 amino acids that is found in the bacteria Salmonella. Hin belongs to the serine recombinase family of DNA invertases in which it relies on the active site serine to initiate DNA cleavage and recombination.Chromosome regionsTriparental mating: Triparental mating is a form of Bacterial conjugation where a conjugative plasmid present in one bacterial strain assists the transfer of a mobilizable plasmid present in a second bacterial strain into a third bacterial strain. Plasmids are introduced into bacteria for such purposes as transformation, cloning, or transposon mutagenesis.DNA-binding proteinMolecular evolution: Molecular evolution is a change in the sequence composition of cellular molecules such as DNA, RNA, and proteins across generations. The field of molecular evolution uses principles of evolutionary biology and population genetics to explain patterns in these changes.Branching order of bacterial phyla (Gupta, 2001): There are several models of the Branching order of bacterial phyla, one of these was proposed in 2001 by Gupta based on conserved indels or protein, termed "protein signatures", an alternative approach to molecular phylogeny. Some problematic exceptions and conflicts are present to these conserved indels, however, they are in agreement with several groupings of classes and phyla.Zuotin: Z-DNA binding protein 1, also known as Zuotin, is a Saccharomyces cerevisiae yeast gene.Genetic variation: right|thumbInfinite alleles model: The infinite alleles model is a mathematical model for calculating genetic mutations. The Japanese geneticist Motoo Kimura and American geneticist James F.List of strains of Escherichia coli: Escherichia coli is a well studied bacterium that was first identified by Theodor Escherich, after whom it was later named.DNA condensation: DNA condensation refers to the process of compacting DNA molecules in vitro or in vivo. Mechanistic details of DNA packing are essential for its functioning in the process of gene regulation in living systems.DNA sequencer: A DNA sequencer is a scientific instrument used to automate the DNA sequencing process. Given a sample of DNA, a DNA sequencer is used to determine the order of the four bases: G (guanine), C (cytosine), A (adenine) and T (thymine).G2-M DNA damage checkpoint: The G2-M DNA damage checkpoint is an important cell cycle checkpoint in eukaryotic organisms ranging from yeast to mammals. This checkpoint ensures that cells don't initiate mitosis before they have a chance to repair damaged DNA after replication.Genetic linkage: Genetic linkage is the tendency of alleles that are located close together on a chromosome to be inherited together during the meiosis phase of sexual reproduction. Genes whose loci are nearer to each other are less likely to be separated onto different chromatids during chromosomal crossover, and are therefore said to be genetically linked.Chromothripsis: Chromothripsis is the phenomenon by which up to thousands of clustered chromosomal rearrangements occur in a single event in localised and confined genomic regions in one or a few chromosomes, and is known to be involved in both cancer and congenital diseases. It occurs through one massive genomic rearrangement during a single catastrophic event in the cell's history.Premature chromosome condensation: Premature chromosome condensation (PCC) occurs in eukaryotic organisms when mitotic cells fuse with interphase cells. Chromatin, a substance that contains genetic material such as DNA, is normally found in a loose bundle inside a cell's nucleus.Direct repeat: Direct repeats are a type of genetic sequence that consists of two or more repeats of a specific sequence.Antitermination: Antitermination is the prokaryotic cell's aid to fix premature termination of RNA synthesis during the transcription of RNA. It occurs when the RNA polymerase ignores the termination signal, and it provides a mechanism whereby one or more genes at the end of an operon can be switched either on or off, depending on the polymerase either recognizing or not recognizing the termination signal.DNA re-replication: DNA re-replication (or simply rereplication) is an undesirable and possibly fatal occurrence in eukaryotic cells in which the genome is replicated more than once per cell cycle. Rereplication is believed to lead to genomic instability and has been implicated in the pathologies of a variety of human cancers.Chi site: A Chi site or Chi sequence is a short stretch of DNA in the genome of a bacterium near which homologous recombination is more likely than expected to occur. Chi sites serve as stimulators of DNA double-strand break repair in bacteria, which can arise from radiation or chemical treatments, or result from replication fork breakage during DNA replication.Synaptonemal complex: right|300px|thumb|A Homologous chromosomes (light blue) align and synapse together via transverse filaments (black lines) and longitudinal filaments (dark blue). Recombination nodules (gray ellipsoids) on the central region may help in completing recombination.NucleoidSticky and blunt ends: DNA end or sticky end refers to the properties of the end of a molecule of DNA or a recombinant DNA molecule. The concept is important in molecular biology, especially in cloning or when subcloning inserts DNA into vector DNA.RuvABC: RuvABC is a complex of three proteins that mediate branch migration and resolve the Holliday junction created during homologous recombination in bacteria. As such, RuvABC is critical to bacterial DNA repair.Excinuclease: Excision endonuclease, also known as excinuclease or UV-Specific Endonuclease, is a nuclease (enzyme) which excises a fragment of nucleotides during DNA repair. The excinuclease cuts out a fragment by hydrolyzing two phosphodiester bonds, one on either side of the lesion in the DNA.Selection (relational algebra): In relational algebra, a selection (sometimes called a restriction to avoid confusion with SQL's use of SELECT) is a unary operation written asComposite transposon: A composite transposon is similar in function to simple transposons and Insertion Sequence (IS) elements in that it has protein coding DNA segments flanked by inverted, repeated sequences that can be recognized by transposase enzymes. A composite transposon, however, is flanked by two separate IS elements which may or may not be exact replicas.Ligation-independent cloning: Ligation-independent cloning (LIC) is a form of molecular cloning that is able to be performed without the use of restriction endonucleases or DNA ligase. This allows genes that have restriction sites to be cloned without worry of chopping up the insert.Deletion (genetics)Protein primary structure: The primary structure of a peptide or protein is the linear sequence of its amino acid structural units, and partly comprises its overall biomolecular structure. By convention, the primary structure of a protein is reported starting from the amino-terminal (N) end to the carboxyl-terminal (C) end.John Payne ToddThermal cyclerCircular bacterial chromosome: A circular bacterial chromosome is a bacterial chromosome in the form of a molecule of circular DNA. Unlike the linear DNA of most eukaryotes, typical bacterial chromosomes are circular.Sister (Sister2Sister song)Excision repair cross-complementing: Excision repair cross-complementing (ERCC) is a set of proteins which are involved in DNA repair.Sgs1: Sgs1, also known as slow growth suppressor 1, is a DNA helicase protein found in Saccharomyces cerevisiae. It is a homolog of the bacterial RecQ helicase.Phenotype microarray: The phenotype microarray approach is a technology for high-throughput phenotyping of cells.Multiple cloning site: A multiple cloning site (MCS), also called a polylinker, is a short segment of DNA which contains many (up to ~20) restriction sites - a standard feature of engineered plasmids. Restriction sites within an MCS are typically unique, occurring only once within a given plasmid.CS-BLASTSignature-tagged mutagenesis: Signature-tagged mutagenesis (STM) is a genetic technique used to study gene function. Recent advances in genome sequencing have allowed us to catalogue a large variety of organisms' genomes, but the function of the genes they contain is still largely unknown.Framework region: In molecular biology, a framework region is a region in the variable domain of a protein which belongs to the immunoglobulin superfamily, and which is less "variable" than the CDR.Nucleic acid structure: Nucleic acid structure refers to the structure of nucleic acids such as DNA and RNA. Chemically speaking, DNA and RNA are very similar.Ferric uptake regulator family: In molecular biology, the ferric uptake regulator (FUR) family of proteins includes metal ion uptake regulator proteins. These are responsible for controlling the intracellular concentration of iron in many bacteria.