| insulin-like growth-factor-binding proteins | A family of soluble proteins that bind insulin-like growth factors and modulate their biological actions at the cellular level. (int j gynaecol obstet 1992;39(1):3-9) (12 Dec 1998) |
|---|---|
| testosterone-oestrogen-binding globulin | A glycoprotein migrating as a beta-globulin. Its molecular weight, 52,000 or 95,000-115,000, indicates that it exists as a dimer. The protein binds testosterone, dihydrotestosterone, and estradiol in the plasma. Changes in its concentration significantly affect the ratio of unbound (biologically active) testosterone to estradiol in plasma. (12 Dec 1998) |
| thyroid binding globulin | <protein> Thyroid binding globulin (TBG) is a plasma protein which binds the majority of thyroid hormone in the bloodstream. Bound thyroid hormone is inactive, only the unbound fraction (0.3%) is considered active. Birth control pills and pregnancy can lead to increased TBG levels in the plasma. Androgens can decrease TBG levels in the plasma. (27 Sep 1997) |
| thyroxine-binding globulin | An alpha-globulin of blood with a strong binding affinity for thyroxine; triiodothyronine is bound to it much less firmly; a deficiency or excess of this protein may occur as a rare benign X-linked disorder. Synonym: thyroxine-binding protein. (05 Mar 2000) |
| thyroxine-binding proteins | A group of proteins that includes thyroxine-binding globulin, a glycoprotein that serves as the major and specific carrier of thyroxine in plasma, accounting for 70-75% of the bound thyroxine; thyroxine-binding prealbumin, an albumin that serves as the secondary carrier, accounting for between 20 and 25% of the bound thyroxine; and serum albumin, which accounts for the remaining bound thyroxine. (12 Dec 1998) |
| fatty acid binding proteins | <biochemistry> Group of small cytosolic proteins that bind fatty acids or other organic solutes. (18 Nov 1997) |
| zero time-binding DNA | DNA that has become the duplex form at the start of a reassociation process. Acronym: DNA (05 Mar 2000) |
| ligand binding site | The site on a protein's surface that binds a ligand; equivalent to the active site if the ligand is the substrate of an enzyme. (05 Mar 2000) |
| acetoacetyl-acyl carrier protein synthase | <enzyme> E coli enzyme, that catalyses condensation of malonyl-acyl carrier protein plus acetyl-acyl carrier protein; not inhibited by cerulenin Registry number: EC 2.3.1.- Synonym: acetoacetyl-acp synthase (26 Jun 1999) |
| acid soluble spore protein | <molecular biology> A DNA binding protein in the spores of some bacteria, thought to stabilise the DNA in an A configuration, so protecting it from cleavage by enzymes or UV light. (18 Nov 1997) |
| acute-phase protein | <haematology> These plasma proteins (in addition to fibrinogen) increase 25% or more in response to inflammation and injury are under direct control of interleukin-6 (IL-6) (hepatocyte-stimulating factor). Other proteins which increase are ceruloplasmin, C3 and C4 which increase 50% or more; alpha-1 acid glycoprotein, alpha-1 antitrypsin, haptoglobin and fibrinogen (the major determinant of viscosity 1 ) which increase two- to fourfold; C-reactive protein (CRP) and serum amyloid A which increase several hundred-fold. Despite long-held clinical opinion to the contrary, available data indicate that neither ESR nor measurement of specific acute-phase reactants are useful in excluding underlying infection or inflammation regardless of the pretest probability. These proteins are secreted into the blood in increased or decreased quantities by hepatocytes in response to trauma, inflammation, or disease. They can serve as inhibitors or mediators of the inflammatory processes. Certain acute-phase proteins have been used to diagnose and follow the course of diseases or as tumour markers. See also: amyloid, c-reactive protein, erythrocyte sedimentation rate, viscosity. (25 Jun 1999) |
| acyl-(acyl-carrier-protein)-phospholipid acyltransferase | <enzyme> Catalyses the formation of phosphatidylethanolamine from acyl-acyl carrier protein and 2-acyl-sn-glycero-3-phosphoethanolamine Registry number: EC 2.3.1.40 Synonym: 2-acyl-gpe acyltransferase, 2-acylglycerophosphoethanolamine acyltransferase (26 Jun 1999) |
| acyl-(acyl-carrier-protein)-UDP-N-acetylglucosamine acyltransferase | <enzyme> E coli enzyme involved in lipid a biosynthesis; uses beta-hydroxymyristoyl-acyl carrier protein to form udp-3-monoacyl-n-acetylglucosamine; amino acid sequence given in second source Registry number: EC 2.3.1.129 Synonym: udp-aguatransferase, lpxa protein, udp-n-acetylglucosamine-3-acyltransferase, udp-n-acetylglucosamine 3-o-acyltransferase, udp-3-o-(r-3-hydroxymyristoyl)glucosamine-n-acyltransferase, lpxd protein, fira gene product, fira protein (26 Jun 1999) |
| acyl carrier protein | <protein> A small (77 peptides long) protein which binds six other enzymes involved in fatty acid synthesis. It was first isolated in E. Coli bacteria. (09 Oct 1997) |
| acyl carrier protein acylase | <enzyme> From E coli Registry number: EC 2.3.1.- Synonym: acp acylase (26 Jun 1999) |