G proteins belong to the larger group of enzymes called GTPases.

Eukaryotic protein kinases are enzymes that belong to a very extensive family of proteins that share a conserved catalytic core.

Type III enzymes belong to the beta-subfamily of N6 adenine methyltransferases, containing the nine motifs that characterise this family, including motif I, the AdoMet binding pocket ( FXGXG ), and motif IV, the catalytic region ( S / D / N ( PP ) Y / F ).

Acinar cells belong to the exocrine pancreas and secrete digestive enzymes into the gut via a system of ducts.

Proteases belong to the class of enzymes known as hydrolases, which catalyse the reaction of hydrolysis of various bonds with the participation of a water molecule.

Galactokinase does not belong to the sugar kinase family, but rather to a class of ATP-dependent enzymes known as the GHMP superfamily.

Arginase belong to the ureohydrolase family of enzymes.

The enzymes which are biosynthetic for eicosanoids ( e. g. glutathione-S-transferases, epoxide hydrolases and carrier proteins ) belong to families whose functions are largely involved with cellular detoxification.

All classes of enoyl-CoA isomerases belong to a family of enzymes, the hydratase / isomerase or crotonase superfamily, and when examined with x-ray crystallography, exhibit a common structural feature of the family, the N-terminal core with a spiral fold composed of four turns, each turn consisting of two beta-sheets and one alpha-helix.

The catalytic action of enzymes relies on several mechanisms including the molecular shape (" induced fit "), bond strain, proximity and orientation of molecules relative to the enzyme, proton donation or withdrawal ( acid / base catalysis ), electrostatic interactions and many others.

The common names of ligase enzymes often include the word " ligase ," such as DNA ligase, an enzyme commonly used in molecular biology laboratories to join together DNA fragments.

Molybdenum-containing enzymes are by far the most common catalysts used by some bacteria to break the chemical bond in atmospheric molecular nitrogen, allowing biological nitrogen fixation.

Certain enzymes within the peroxisome, by using molecular oxygen, remove hydrogen atoms from specific organic substrates ( labeled as R ), in an oxidative reaction, producing hydrogen peroxide ( H < sub > 2 </ sub > O < sub > 2 </ sub >, itself toxic ):

Cleavage at these random sites follows a process of DNA translocation, which shows that these enzymes are also molecular motors.

The commercial availability of reverse transcriptase greatly improved knowledge in the area of molecular biology, as, along with other enzymes, it allowed scientists to clone, sequence, and characterise DNA.

Some of these enzymes are used in molecular biology ( for example, heat-stable DNA polymerases for PCR ), and in washing agents.

Epigenetic research uses a wide range of molecular biologic techniques to further our understanding of epigenetic phenomena, including chromatin immunoprecipitation ( together with its large-scale variants ChIP-on-chip and ChIP-Seq ), fluorescent in situ hybridization, methylation-sensitive restriction enzymes, DNA adenine methyltransferase identification ( DamID ) and bisulfite sequencing.

Early attempts at molecular systematics were also termed as chemotaxonomy and made use of proteins, enzymes, carbohydrates, and other molecules that were separated and characterized using techniques such as chromatography.

By utilizing molecular competition ( in vitro evolution ) of a candidate enzyme mixture, a pair of RNA enzymes emerged, in which each synthesizes the other from synthetic oligonucleotides, with no protein present.

Porphyrins have conjugated molecular ring systems ( macrocycles ) that appear in many enzymes of biological systems.

In 2002, researchers from the Weizmann Institute of Science in Rehovot, Israel, unveiled a programmable molecular computing machine composed of enzymes and DNA molecules instead of silicon microchips.

These enzymes became known as restriction enzymes and developed into one of the main molecular tools in molecular biology.

They often act as enzymes, performing biochemical reactions including cell signaling, molecular transportation, and cellular regulation.

It is the source of the heat-resistant enzyme Taq DNA polymerase, one of the most important enzymes in molecular biology because of its use in the polymerase chain reaction ( PCR ) DNA amplification technique.

In addition, the molecular phylogenies of aaRSs are often not consistent with accepted organismal phylogenies, e. g. they violate the so-called canonical phylogenetic pattern shown by most other enzymes for the three domains of life-Archaea, Bacteria, and Eukarya.

In later studies he applied molecular biology techniques to understand the structure and function of mitochondrial enzymes involved in steroid hormone biosynthesis.

# Sulfide is an essential component of some enzymes, and molecular oxygen oxidizes this to form disulfide, thus inactivating certain enzymes.

Duclaux ’ s study on the metabolism of nutrients will not have immediate practical applications but will reveal how extensive is the field of enzymes and open new roads that will lead biology to extend the knowledge on life ’ s mechanisms on a molecular level.

They catalyse the hydrolysis of interior peptide bonds in peptide chains, as opposed to exopeptidases ( another class of enzymes, that catalyse the hydrolysis of terminal peptide bonds, liberating one free amino acid at a time ).

Dirigent proteins are members of a class of proteins which dictate the stereochemistry of a compound synthesized by other enzymes.

In the last step, a member of a highly diverse class of enzymes known as ubiquitin ligases ( E3 ) recognizes the specific protein to be ubiquitinated and catalyzes the transfer of ubiquitin from E2 to this target protein.

In the 1990s and early 2000s, new enzymes from this family were discovered that did not follow all the classical criteria of this enzyme class, and new subfamily nomenclature was developed to divide this large family into subcategories based on deviations from typical characteristics of type II enzymes.

* Dipeptidyl peptidase, a class of enzymes which cleave dipeptides from proteins and peptides

ATPases are a class of enzymes that catalyze the decomposition of adenosine triphosphate ( ATP ) into adenosine diphosphate ( ADP ) and a free phosphate ion.

Lipid asymmetry arises, at least in part, from the fact that most phospholipids are synthesised and initially inserted into the inner monolayer: those that constitute the outer monolayer are then transported to the inner monolayer by a class of enzymes called flippases.

CBD is also believed to regulate the body ’ s metabolism of THC by inactivating cytochrome P450, an important class of enzymes that metabolize drugs.

** Minor enzymes include salivary acid phosphatases A + B, N-acetylmuramoyl-L-alanine amidase, NAD ( P ) H dehydrogenase ( quinone ), superoxide dismutase, glutathione transferase, class 3 aldehyde dehydrogenase, glucose-6-phosphate isomerase, and tissue kallikrein ( function unknown ).

A number of studies have indicated keratoconic corneas show signs of increased activity by proteases, a class of enzymes that break some of the collagen cross-linkages in the stroma, with a simultaneous reduced expression of protease inhibitors.

* Cathepsin, a class of enzymes

Luciferase is a generic term for the class of oxidative enzymes used in bioluminescence and is distinct from a photoprotein.

Helicases are a class of enzymes vital to all living organisms.

These enzymes are members of the larger class of aldehyde dehydrogenases.

As of late 2007, 75 structures have been solved for this class of enzymes, with PDB accession codes,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, and.

Superoxide dismutases ( SOD ) are a class of enzymes that catalyze the dismutation of superoxide into oxygen and hydrogen peroxide.

Protease inhibitors ( PIs ) are a class of drugs used to treat or prevent infection by viruses, including HIV and Hepatitis C. PIs prevent viral replication by inhibiting the activity of proteases, e. g. HIV-1 protease, enzymes used by the viruses to cleave nascent proteins for final assembly of new virions.

* Nitric oxide synthase, a class of enzymes

* Protein kinase A, a class of cAMP-dependent enzymes

These are now called resonant-energy-transferring molecules of the chlorophyll class, which transfer what is considered electromagnetic energy, from one to its neighbor with no participation of electrons nor enzymes.