Polymerase

"A polymerase (EC 2.7.7.6/7/19/48/49) is an enzyme whose central function is associated with polymers of nucleic acids such as RNA and DNA. The primary function of a polymerase is the polymerization of new DNA or RNA against an existing DNA or RNA template in the processes of replication and transcription. In association with a cluster of other enzymes and proteins, they take nucleotides from solvent, and catalyse the synthesis of a polynucleotide sequence against anucleotide template strand using base-pairing interactions."

"It is an accident of history that the enzymes responsible for the catalytic production of other biopolymers are not also referred to as polymerases."

"One particular polymerase, from the thermophilic bacterium, Thermus aquaticus (Taq) (PDB 1BGX, EC 2.7.7.7) is of vital commercial importance due to its use in the polymerase chain reaction, a widely used technique of molecular biology.

Other well-known polymerases include:

• Terminal Deoxynucleotidyl Transferase (TDT), which lends diversity to antibody heavy chains

• Reverse Transcriptase, an enzyme used by RNA retroviruses like HIV, which is used to create a complementary strand to the preexisting strand of viral RNA before it can be integrated into theDNA of the host cell. It is also a major target for antiviral drugs."

Thiomersal

"Thiomersal (INN), and commonly known in the US as thimerosal, is  an organomercury compound. This compound is a well established antiseptic and antifungal agent."

"The pharmaceutical corporation Eli Lilly and Company gave thiomersal the trade name Merthiolate and it has been used as a preservative in vaccines,immunoglobulin preparations, skin test antigens, antivenins, ophthalmic and nasal products, and tattoo inks. Its use as a vaccine preservative iscontroversial, and it is being phased out from routine childhood vaccines in the United States, the European Union, and a few other countries."

"Thiomersal features mercury(II) with a coordination number 2, i.e. two ligands are attached to Hg, the thiolate and the ethyl group. The carboxylate group is not coordinated, but confers solubility in water. Like other two-coordinate Hg(II) compounds, the coordination geometry is linear, with a 180° S-Hg-C angle. Typically, organomercury thiolate compounds are prepared from organomercury chlorides."

Phosphine

"Phosphine (IUPAC name: phosphane) is the compound with the chemical formula PH₃. It is a colorless, flammable, toxic gas. Pure phosphine is odorless, but technical grade samples have a highly unpleasant odor like garlic or rotting fish, due to the presence of substituted phosphine and diphosphine (P₂H₄). With traces of P₂H₄ present, PH₃ is spontaneously flammable in air, burning with a luminous flame. Phosphines are also a group of organophosphorus compounds with the formula R₃P (R = organic derivative). Organophosphines are important in catalysts where they complex to various metal ions; complexes derived from a chiral phosphine can catalyze reactions to give chiral products."

"PH₃ is a trigonal pyramidal molecule with C_3v molecular symmetry. The length of the P-H bond 1.42 Å, the H-P-H bond angles are 93.5°. The dipole moment is 0.58 D, which increases with substitution of methyl groups in the series: CH₃PH₂, 1.10 D; (CH₃)₂PH, 1.23 D; (CH₃)₃P, 1.19 D. In contrast, the dipole moments of amines decrease with substitution, starting with ammonia, which has a dipole moment of 1.47 D. The low dipole moment and almost orthogonal bond angles lead to the conclusion that in PH₃ the P-H bonds are almost entirely pσ(P) – sσ(H) and phosphorus 3s orbital contributes little to the bonding between phosphorus and hydrogen in this molecule. For this reason, the lone pair on phosphorus may be regarded as predominantly formed by the 3s orbital of phosphorus. The upfield chemical shift of the phosphorus atom in the ³¹P NMR spectrum accords with the conclusion that the lone pair electrons occupy the 3s orbital (Fluck, 1973). This electronic structure leads to a lack of nucleophilicity and an ability to form only weak hydrogen bonds."

Aniline

"Aniline, phenylamine or aminobenzene is an organic compound with the formula C₆H₅NH₂. Consisting of a phenyl group attached to an amino group, aniline is the prototypical aromatic amine. Being a precursor to many industrial chemicals, its main use is in the manufacture of precursors to polyurethane. Like most volatile amines, it possesses the somewhat unpleasant odour of rotten fish. It ignites readily, burning with a smoky flame characteristic of aromatic compounds. Aniline is colorless, but it slowly oxidizes and resinifies in air, giving a red-brown tint to aged samples."

"Many derivatives of aniline can be prepared in similar fashion from nitrated aromatic compounds. Nitration followed by reduction of toluene affords toluidines. Nitration of chlorobenzene and related derivatives and reduction of the nitration products gives aniline derivatives, e.g. 4-chloroaniline."

Norbornane

"Norbornane (also known as bicyclo[2.2.1]heptane) is an organic compound and a saturated hydrocarbon with chemical formula C₇H₁₂. It is a crystallinecompound with melting point 88 °C. The carbon skeleton is a cyclohexane ring bridged by a methylene group in the 1,4- position, and is a bridged bicycliccompound. The compound can be synthesized by hydrogenation of the related compounds norbornene and norbornadiene. The norbornyl cation (C₇H₁₁⁺) is of great scientific interest in relation to non-classical ions."

"The compound got its name from bornane which has three methyl groups and is the carbon skeleton for camphor (bornanone). In bornane, there is one methyl group attached to a carbon at the base of the bridge and two methyl groups attached to the carbon at the apex of the bridge. The prefix nor refers to the stripping of the methyl groups from the original bornane."

Immunoglobin A

"Immunoglobulin A (IgA) is an antibody that plays a critical role in mucosal immunity. More IgA is produced in mucosal linings than all other types of antibody combined;^[1] between three and five grams are secreted into the intestinal lumen each day.^[2] This accumulates to 75% of the total immunoglobulin produced in the entire body."

"IgA has two subclasses (IgA1 and IgA2) and can exist in a dimeric form called secretory IgA (sIgA). In its secretory form, IgA is the main immunoglobulin found in mucous secretions, including tears, saliva, colostrum and secretions from the genitourinary tract, gastrointestinal tract, prostate and respiratory epithelium. It is also found in small amounts in blood. The secretory component of sIgA protects the immunoglobulin from being degraded by proteolytic enzymes, thus sIgA can survive in the harsh gastrointestinal tract environment and provide protection against microbes that multiply in body secretions.^[4] IgA is a poor activator of thecomplement system, and opsonises only weakly. Its heavy chains are of the type α."

Diphenyl Ether

"Diphenyl ether is the organic compound with the formula O(C₆H₅)₂. The molecule is subject to reactions typical of other phenyl rings, including hydroxylation, nitration, halogenation, sulfonation, and Friedel-Crafts alkylation or acylation.^[1] This simple diaryl ether enjoys a variety of niche applications."

"The main application of diphenyl ether is as a eutectic mixture with biphenyl, used as a heat transfer medium. Such a mixture is well-suited for heat transfer applications because of the relatively large temperature range of its liquid state."

"Diphenyl ether is a starting material in the production of phenoxathiin via the Ferrario reaction.^[4] Phenoxathiin is used in polyamide and polyimideproduction."

Nitromethane

"Nitromethane is an organic compound with the chemical formula CH₃NO₂. It is the simplest organic nitro compound. It is a slightly viscous, highly polar liquid commonly used as a solvent in a variety of industrial applications such as in extractions, as a reaction medium, and as a cleaning solvent. As an intermediate in organic synthesis, it is used widely in the manufacture of pharmaceuticals, pesticides, explosives, fibers, and coatings. It is also used as aracing fuel in Top Fuel drag racing, and as an important component in the fuel for miniature internal combustion engines that are used in radio-controlled models."

"The principal use of nitromethane is as a stabilizer for chlorinated solvents, which are used in dry cleaning, semiconductor processing, and degreasing. It is also used most effectively as a solvent or dissolving agent for acrylate monomers, such as cyanoacrylates (more commonly known as "super-glue")."

Anthracene

"Anthracene is a solid polycyclic aromatic hydrocarbon consisting of three fused benzene rings. It is a component of coal-tar. Anthracene is used in theproduction of the red dye alizarin and other dyes. Anthracene is colorless but exhibits a blue (400-500 nm peak) fluorescence under ultraviolet light."

"In 2010, a strong absorption band of anthracene was observed along a line of sight to a star in the open cluster IC 348, and this may be associated with an intervening molecular cloud."

"A variety of anthracene derivatives find niche uses. Derivatives having a hydroxyl group are 1-hydroxyanthracene and 2-hydroxyanthracene, homologous to phenol and naphthols, and hydroxyanthracene (also called anthrol, and anthracenol)^[5][6] are pharmacologically active. Anthracene may also be found with multiple hydroxyl groups, as in 9,10-dihydroxyanthracene."

Sterols

"Sterols, also known as steroid alcohols, are a subgroup of the steroids and an important class of organic molecules. They occur naturally in plants, animals, and fungi, with the most familiar type of animal sterol being cholesterol. Cholesterol is vital to cellular function, and a precursor to fat-soluble vitamins and steroid hormones."

"Sterols of plants are called phytosterols and sterols of animals are called zoosterols. Important zoosterols are cholesterol; notable phytosterols include campesterol, sitosterol, and stigmasterol.Ergosterol is a sterol present in the cell membrane of fungi, where it serves a role similar to cholesterol in animal cells."

"Sterols and related compounds play essential roles in the physiology of eukaryotic organisms. For example, cholesterol forms part of the cellular membrane in animals, where it affects the cell membrane's fluidity and serves as secondary messenger in developmental signaling. In humans and other animals, corticosteroids, such as cortisol act as signaling compounds in cellular communication and general metabolism."