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SPTLC1
Serine palmitoyltransferase, long chain base subunit 1, also known as SPTLC1, is a protein which in humans is encoded by the ''SPTLC1'' gene. Serine palmitoyltransferase, which consists of two different subunits, is the initial enzyme in sphingolipid biosynthesis. It converts L- serine and palmitoyl CoA to 3-oxosphinganine with pyridoxal 5'-phosphate Pyridoxal phosphate (PLP, pyridoxal 5'-phosphate, P5P), the active form of vitamin B6, is a coenzyme in a variety of enzymatic reactions. The International Union of Biochemistry and Molecular Biology has catalogued more than 140 PLP-dependent ac ... as a cofactor. The product of this gene is the long chain base subunit 1 of serine palmitoyltransferase. Mutations in this gene were identified in patients with hereditary sensory neuropathy type 1, macular disease, and juvenile amyotrophic lateral sclerosis. Alternatively spliced variants encoding different isoforms have been identified. References Further reading * * * * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serine C-palmitoyltransferase
In enzymology, a serine C-palmitoyltransferase () is an enzyme that catalyzes the chemical reaction: :palmitoyl-CoA + L-serine \rightleftharpoons CoA + 3-dehydro-D-sphinganine + CO2 Thus, the two substrates of this enzyme are palmitoyl-CoA and L-serine, whereas its 3 products are CoA, 3-dehydro-D-sphinganine, and CO2. This reaction is a key step in the biosynthesis of sphingosine which is a precursor of many other sphingolipids. This enzyme participates in sphingolipid metabolism. It employs one cofactor, pyridoxal phosphate. Nomenclature This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is palmitoyl-CoA:L-serine C-palmitoyltransferase (decarboxylating). Other names in common use include: * serine palmitoyltransferase, * SPT, 3-oxosphinganine synthetase, and * acyl-CoA:serine C-2 acyltransferase decarboxylating. Structure Serine C-pal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphingolipid
Sphingolipids are a class of lipids containing a backbone of sphingoid bases, a set of aliphatic amino alcohols that includes sphingosine. They were discovered in brain extracts in the 1870s and were named after the mythological sphinx because of their enigmatic nature. These compounds play important roles in signal transduction and cell recognition. Sphingolipidoses, or disorders of sphingolipid metabolism, have particular impact on neural tissue. A sphingolipid with an R group consisting of a hydrogen atom only is a ceramide. Other common R groups include phosphocholine, yielding a sphingomyelin, and various sugar monomers or dimers, yielding cerebrosides and globosides, respectively. Cerebrosides and globosides are collectively known as glycosphingolipids. Structure The long-chain bases, sometimes simply known as sphingoid bases, are the first non-transient products of '' de novo'' sphingolipid synthesis in both yeast and mammals. These compounds, specifically known as phy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serine
Serine (symbol Ser or S) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α- amino group (which is in the protonated − form under biological conditions), a carboxyl group (which is in the deprotonated − form under biological conditions), and a side chain consisting of a hydroxymethyl group, classifying it as a polar amino acid. It can be synthesized in the human body under normal physiological circumstances, making it a nonessential amino acid. It is encoded by the codons UCU, UCC, UCA, UCG, AGU and AGC. Occurrence This compound is one of the naturally occurring proteinogenic amino acids. Only the L- stereoisomer appears naturally in proteins. It is not essential to the human diet, since it is synthesized in the body from other metabolites, including glycine. Serine was first obtained from silk protein, a particularly rich source, in 1865 by Emil Cramer. Its name is derived from the Latin for silk, ''sericum''. Serine's structure w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palmitoyl CoA
Palmitoyl-CoA is an acyl-CoA thioester. It is an "activated" form of palmitic acid and can be transported into the mitochondrial matrix by the carnitine shuttle system (which transports fatty acyl-CoA molecules into the mitochondria), and once inside can participate in beta-oxidation. Alternatively, palmitoyl-CoA is used as a substrate in the biosynthesis of sphingosine (this biosynthetic pathway does not require transfer into the mitochondria). Biosynthesis Palmitoyl CoA formed from palmitic acid, in the reaction below. Palmitate + CoA-SH + ATP -> Palmitoyl-CoA + AMP + Pyrophosphate This reaction is often referred to as the "activation" of a fatty acid. The activation is catalyzed by palmitoyl-coenzyme A synthetase and the reaction proceeds through a two step mechanism, in which palmitoyl-AMP is an intermediate. The reaction is driven to completion by the exergonic hydrolysis of pyrophosphate. The activation of fatty acids occurs in the cytosol and beta-oxidation occ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyridoxal Phosphate
Pyridoxal phosphate (PLP, pyridoxal 5'-phosphate, P5P), the active form of vitamin B6, is a coenzyme in a variety of enzymatic reactions. The International Union of Biochemistry and Molecular Biology has catalogued more than 140 PLP-dependent activities, corresponding to ~4% of all classified activities. The versatility of PLP arises from its ability to covalently bind the substrate, and then to act as an electrophilic catalyst, thereby stabilizing different types of carbanionic reaction intermediates. Role as a coenzyme PLP acts as a coenzyme in all transamination reactions, and in certain decarboxylation, deamination, and racemization reactions of amino acids. The aldehyde group of PLP forms a Schiff-base linkage (internal aldimine) with the ε-amino group of a specific lysine group of the aminotransferase enzyme. The α-amino group of the amino acid substrate displaces the ε-amino group of the active-site lysine residue in a process known as transaldimination. The resulti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
