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Sterol Carrier Protein
Sterol carrier proteins (also known as nonspecific lipid transfer proteins) is a family of proteins that transfer steroids and probably also phospholipids and gangliosides between cellular membranes. These proteins are different from plant nonspecific lipid transfer proteins but structurally similar to small proteins of unknown function from Thermus thermophilus. This domain is involved in binding sterols. The human sterol carrier protein 2 (SCP2) is a basic protein that is believed to participate in the intracellular transport of cholesterol and various other lipids. Human proteins containing this domain HSD17B4; HSDL2; SCP2; STOML1; See also *Steroidogenic acute regulatory protein and START domain References External linksSterol carrier proteinsin SCOPSCP-2 sterol transfer familyin Pfam Pfam is a database of protein families that includes their annotations and multiple sequence alignments generated using hidden Markov models. The most recent version, P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steroid
A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and as signaling molecules. Hundreds of steroids are found in plants, animals and fungi. All steroids are manufactured in cells from the sterols lanosterol ( opisthokonts) or cycloartenol (plants). Lanosterol and cycloartenol are derived from the cyclization of the triterpene squalene. The steroid core structure is typically composed of seventeen carbon atoms, bonded in four " fused" rings: three six-member cyclohexane rings (rings A, B and C in the first illustration) and one five-member cyclopentane ring (the D ring). Steroids vary by the functional groups attached to this four-ring core and by the oxidation state of the rings. Sterols are forms of steroids with a hydroxy group at position three and a skeleton derived from cholesta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phospholipid
Phospholipids, are a class of lipids whose molecule has a hydrophilic "head" containing a phosphate group and two hydrophobic "tails" derived from fatty acids, joined by an alcohol residue (usually a glycerol molecule). Marine phospholipids typically have omega-3 fatty acids EPA and DHA integrated as part of the phospholipid molecule. The phosphate group can be modified with simple organic molecules such as choline, ethanolamine or serine. Phospholipids are a key component of all cell membranes. They can form lipid bilayers because of their amphiphilic characteristic. In eukaryotes, cell membranes also contain another class of lipid, sterol, interspersed among the phospholipids. The combination provides fluidity in two dimensions combined with mechanical strength against rupture. Purified phospholipids are produced commercially and have found applications in nanotechnology and materials science. The first phospholipid identified in 1847 as such in biological tissues wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ganglioside
A ganglioside is a molecule composed of a glycosphingolipid (ceramide and oligosaccharide) with one or more sialic acids (e.g. ''N''-acetylneuraminic acid, NANA) linked on the sugar chain. NeuNAc, an acetylated derivative of the carbohydrate sialic acid, makes the head groups of gangliosides anionic at pH 7, which distinguishes them from globosides. The name ''ganglioside'' was first applied by the German scientist Ernst Klenk in 1942 to lipids newly isolated from ganglion cells of the brain. More than 60 gangliosides are known, which differ from each other mainly in the position and number of NANA residues. It is a component of the cell plasma membrane that modulates cell signal transduction events, and appears to concentrate in lipid rafts. Recently, gangliosides have been found to be highly important molecules in immunology. Natural and semisynthetic gangliosides are considered possible therapeutics for neurodegenerative disorders. Location Gangliosides are present a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermus Thermophilus
''Thermus thermophilus'' is a Gram-negative bacterium used in a range of biotechnological applications, including as a model organism for genetic manipulation, structural genomics, and systems biology. The bacterium is extremely thermophilic, with an optimal growth temperature of about . ''Thermus thermophilus'' was originally isolated from a thermal vent within a hot spring in Izu, Japan by Tairo Oshima and Kazutomo Imahori. The organism has also been found to be important in the degradation of organic materials in the thermogenic phase of composting. ''T. thermophilus'' is classified into several strains, of which HB8 and HB27 are the most commonly used in laboratory environments. Genome analyses of these strains were independently completed in 2004. Cell Structure ''Thermus thermophilus'' is a Gram-negative bacterium with an outer membrane that is composed of phospholipids and lipopolysaccharides. This bacterium also has a thin peptidoglycan (also known as murein) layer, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SCP2
Non-specific lipid-transfer protein also known as sterol carrier protein 2 (SCP-2) or propanoyl-CoA C-acyltransferase is a protein that in humans is encoded by the ''SCP2'' gene. Function This gene encodes two proteins: sterol carrier protein X (SCPx) and sterol carrier protein 2 (SCP2), as a result of transcription initiation from 2 independently regulated promoters. The transcript initiated from the proximal promoter encodes the longer SCPx protein, and the transcript initiated from the distal promoter encodes the shorter SCP2 protein, with the 2 proteins sharing a common C-terminus. Evidence suggests that the SCPx protein is a peroxisome-associated thiolase that is involved in the oxidation of branched chain fatty acids, while the SCP2 protein is thought to be an intracellular lipid transfer protein. Alternative splicing of this gene produces multiple transcript variants, some encoding different isoforms. The full-length nature of all transcript variants has not been determi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HSD17B4
D-bifunctional protein (DBP), also known as peroxisomal multifunctional enzyme type 2 (MFP-2), as well as 17β-hydroxysteroid dehydrogenase type IV (17β-HSD type IV) is a protein that in humans is encoded by the ''HSD17B4'' gene. It's an alcohol oxidoreductase, specifically 17β-Hydroxysteroid dehydrogenase. It is involved in fatty acid β-oxidation and steroid metabolism (cf. steroidogenesis). Function The HSD17B4 gene encodes an enzyme involved in peroxisomal fatty acid beta-oxidation. It was first identified as a 17-beta-estradiol dehydrogenase (Leenders et al., 1996; van Grunsven et al., 1998). Peroxisomal beta-oxidation of fatty acids, originally described by Lazarow and de Duve (1976), is catalyzed by 3 enzymes: acyl-CoA oxidase (see, e.g., ACOX1, MIM 609751); the 'D-bifunctional enzyme,' with enoyl-CoA hydratase and D-3-hydroxyacyl-CoA dehydrogenase activity, and 3-ketoacyl-CoA thiolase Thiolases, also known as acetyl-coenzyme A acetyltransferases (ACAT), ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HSDL2
{{disambiguation ...
HSDL may refer to: *Dilling Airport *Homeland Security Digital Library The Center for Homeland Defense and Security at the Naval Postgraduate School (NPS) in Monterey, California is a school focusing on homeland security education. The Center's programs and resources have been developed to advance the study of home ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
STOML1
Stomatin-like protein 1 is a protein that in humans is encoded by the ''STOML1'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b .... References Further reading * * * * * * * * {{gene-15-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steroidogenic Acute Regulatory Protein
The steroidogenic acute regulatory protein, commonly referred to as StAR (STARD1), is a transport protein that regulates cholesterol transfer within the mitochondria, which is the rate-limiting step in the production of steroid hormones. It is primarily present in steroid-producing cells, including theca cells and luteal cells in the ovary, Leydig cells in the testis and cell types in the adrenal cortex. Function Cholesterol needs to be transferred from the outer mitochondrial membrane to the inner membrane where cytochrome P450scc enzyme (CYP11A1) cleaves the cholesterol side chain, which is the first enzymatic step in all steroid synthesis. The aqueous phase between these two membranes cannot be crossed by the lipophilic cholesterol, unless certain proteins assist in this process. A number of proteins have historically been proposed to facilitate this transfer including: sterol carrier protein 2 (SCP2), steroidogenic activator polypeptide (SAP), peripheral benzodia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
START Domain
START (StAR-related lipid-transfer) is a lipid-binding domain in StAR, HD-ZIP and signalling proteins. The archetypical domain is found in StAR ( Steroidogenic acute regulatory protein), a mitochondrial protein that is synthesized in steroid-producing cells. StAR initiates steroid production by mediating the delivery of cholesterol to the first enzyme in steroidogenic pathway. The START domain is critical for this activity, perhaps through the binding of cholesterol. Following the discovery of StAR, 15 START-domain-containing proteins (termed STARD1 through STARD15) were subsequently identified in vertebrates as well as other that are related. Thousands of proteins containing at least one START domain have been determined in invertebrates, bacteria and plants to form a larger superfamily, variously known as START, Bet v1-like or SRPBCC (START/RHOalphaC/ PITP/Bet v1/CoxG/CalC) domain proteins, all of which bind hydrophobic ligands. In the case of plants, many of the START pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Classification Of Proteins
The Structural Classification of Proteins (SCOP) database is a largely manual classification of protein structural domains based on similarities of their structures and amino acid sequences. A motivation for this classification is to determine the evolutionary relationship between proteins. Proteins with the same shapes but having little sequence or functional similarity are placed in different superfamilies, and are assumed to have only a very distant common ancestor. Proteins having the same shape and some similarity of sequence and/or function are placed in "families", and are assumed to have a closer common ancestor. Similar to CATH and Pfam databases, SCOP provides a classification of individual structural domains of proteins, rather than a classification of the entire proteins which may include a significant number of different domains. The SCOP database is freely accessible on the internet. SCOP was created in 1994 in the Centre for Protein Engineering and the La ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pfam
Pfam is a database of protein families that includes their annotations and multiple sequence alignments generated using hidden Markov models. The most recent version, Pfam 35.0, was released in November 2021 and contains 19,632 families. Uses The general purpose of the Pfam database is to provide a complete and accurate classification of protein families and domains. Originally, the rationale behind creating the database was to have a semi-automated method of curating information on known protein families to improve the efficiency of annotating genomes. The Pfam classification of protein families has been widely adopted by biologists because of its wide coverage of proteins and sensible naming conventions. It is used by experimental biologists researching specific proteins, by structural biologists to identify new targets for structure determination, by computational biologists to organise sequences and by evolutionary biologists tracing the origins of proteins. Early genome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
