In a dynamical system, bistability means the system has two stable equilibrium states. Something that is bistable can be resting in either of two states. These rest states need not be symmetric with respect to stored energy. An example of a mechanical device which is bistable is a light switch. The switch lever is designed to rest in the "on" or "off" position, but not between the two. Bistable behavior can occur in mechanical linkages, electronic circuits, nonlinear optical systems, chemical reactions, and physiological and biological systems.
Aspartate transaminase (AST) or aspartate aminotransferase, also known as AspAT/ASAT/AAT or (serum) glutamic oxaloacetic transaminase, is a pyridoxal phosphate (PLP)-dependent transaminase enzyme that was first described by Arthur Karmen and colleagues in 1954. AST catalyzes the reversible transfer of an α-amino group between aspartate and glutamate and, as such, is an important enzyme in amino acid metabolism. AST is found in the liver, heart, skeletal muscle, kidneys, brain, and red blood cells. Serum AST level, serum ALT level, and their ratio are commonly measured clinically as biomarkers for liver health. The tests are part of blood panels.
CD38 (cluster of differentiation 38), also known as cyclic ADP ribose hydrolase is a glycoprotein found on the surface of many immune cells (white blood cells), including CD4+, CD8+, B lymphocytes and natural killer cells. CD38 also functions in cell adhesion, signal transduction and calcium signaling.
Xanthine dehydrogenase, also known as XDH, is a protein that, in humans, is encoded by the XDH gene.
In enzymology, a 2',3'-cyclic-nucleotide 2'-phosphodiesterase (EC 3.1.4.16) is an enzyme that catalyzes the chemical reaction
In enzymology, a serine C-palmitoyltransferase (EC 2.3.1.50) is an enzyme that catalyzes the chemical reaction:
In enzymology, an ADP-specific glucokinase also known as ADP-dependent glucokinase is an enzyme that catalyzes the chemical reaction
Ribonuclease pancreatic is an enzyme that in humans is encoded by the RNASE1 gene.
Adenylyl cyclase type 3 is an enzyme that in humans is encoded by the ADCY3 gene.
Peptidyl-prolyl cis-trans isomerase FKBP1B is an enzyme that in humans is encoded by the FKBP1B gene.
BR serine/threonine-protein kinase 2 is an enzyme that in humans is encoded by the BRSK2 gene.
2',3'-Cyclic-nucleotide 3'-phosphodiesterase also known as CNPase is an enzyme that in humans is encoded by the CNP gene.
Prenylated flavonoids or prenylflavonoids are a sub-class of flavonoids. They are widely distributed throughout the plant kingdom. Some are known to have phytoestrogenic or antioxidant properties. They are given in the list of adaptogens in herbalism. Chemically they have a prenyl group attached to their flavonoid backbone. It is usually assumed that the addition of hydrophobic prenyl groups facilitate attachment to cell membranes. Prenylation may increase the potential activity of its original flavonoid.
N,N'-diacetylchitobiose phosphorylase is an enzyme with the systematic name N,N'-diacetylchitobiose:phosphate N-acetyl-D-glucosaminyltransferase. This enzyme was found in the genus Vibrio initially but has now been found to be taken up by Escherichia coli as well as many other bacteria. One study shows that Escherichia coli can replicate on a medium that is just composed of GlcNAc a product of phosphorylation of N,N'-diacetylchitobiose as the sole source of carbon. Because E. coli can go on this medium, the enzyme is present. The enzyme has also been found in multiple eukaryotic cells as well, especially in eukaryotes that make chitin and break chitin down. It is believed that N,N'-diacetylchitobiose phosphorylase is an integral part of the phosphoenolpyruvate:glucose phosphotransferase system (PTS). It is assumed that it is involved with Enzyme Complex II of the PTS and is involved with the synthesis of chitin. The enzyme is specific for N,N'-diacetylchitobiose.
3',5'-cyclic-AMP phosphodiesterase (EC 3.1.4.53, cAMP-specific phosphodiesterase, cAMP-specific PDE, PDE1, PDE2A, PDE2B, PDE4, PDE7, PDE8, PDEB1, PDEB2) is an enzyme with systematic name 3',5'-cyclic-AMP 5'-nucleotidohydrolase. This enzyme catalyses the following chemical reaction
Bacillus subtilis ribonuclease is an enzyme. This enzyme catalyses the following chemical reaction
Sphingomyelin deacylase (EC 3.5.1.109, SM deacylase, GcSM deacylase, glucosylceramide sphingomyelin deacylase, sphingomyelin glucosylceramide deacylase, SM glucosylceramide GCer deacylase, SM-GCer deacylase, SMGCer deacylase) is an enzyme with systematic name N-acyl-sphingosylphosphorylcholine amidohydrolase. This enzyme catalyses the following chemical reaction
UDP-arabinopyranose mutase is an enzyme with systematic name UDP-arabinopyranose pyranomutase. This enzyme catalyses the following chemical reaction
Pseudoenzymes are variants of enzymes that are catalytically deficient, meaning that they perform little or no enzyme catalysis. They are believed to be represented in all major enzyme families in the kingdoms of life. Pseudoenzymes are becoming increasingly important to analyse, especially as the bioinformatic analysis of genomes reveals their ubiquity. Their important regulatory and sometimes disease-associated functions in metabolic and signalling pathways are also shedding new light on the non-catalytic functions of active enzymes, and are suggesting new ways to target and interpret cellular signalling mechanisms using small molecules and drugs. The most intensively analyzed, and certainly the best understood pseudoenzymes in terms of cellular signalling functions are probably the pseudokinases, the pseudoproteases and the pseudophosphatases.
