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Naringenin-chalcone Synthase
Chalcone synthase or naringenin-chalcone synthase (CHS) is an enzyme ubiquitous to higher plants and belongs to a family of polyketide synthase enzymes (PKS) known as type III PKS. Type III PKSs are associated with the production of chalcones, a class of organic compounds found mainly in plants as natural defense mechanisms and as synthetic intermediates. CHS was the first type III PKS to be discovered. It is the first committed enzyme in flavonoid biosynthesis. The enzyme catalyzes the conversion of 4-coumaroyl-CoA and malonyl-CoA to naringenin chalcone. Function CHS catalysis serves as the initial step for flavonoid biosynthesis. Flavonoids are important plant secondary metabolites that serve various functions in higher plants. These include pigmentation, UV protection, fertility, antifungal defense and the recruitment of nitrogen-fixing bacteria. CHS is believed to act as a central hub for the enzymes involved in the flavonoid pathway. Studies have shown that these enzymes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyketide Synthase
Polyketide synthases (PKSs) are a family of multi- domain enzymes or enzyme complexes that produce polyketides, a large class of secondary metabolites, in bacteria, fungi, plants, and a few animal lineages. The biosyntheses of polyketides share striking similarities with fatty acid biosynthesis. The PKS genes for a certain polyketide are usually organized in one operon or in gene clusters. Type I and type II PKSs form either large modular protein complexes or dissociable molecular assemblies; type III PKSs exist as smaller homodimeric proteins. Classification PKSs can be classified into three types: * Type I PKSs are large, complex protein structures with multiple modules which in turn consist of several domains that are usually covalently connected to each other and fulfill different catalytic steps. The minimal composition of a type I PKS module consists of an acyltransferase (AT) domain, which is responsible for choosing the building block to be used, a keto synthase (KS) do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coenzyme A
Coenzyme A (CoA, SHCoA, CoASH) is a coenzyme, notable for its role in the Fatty acid metabolism#Synthesis, synthesis and Fatty acid metabolism#.CE.B2-Oxidation, oxidation of fatty acids, and the oxidation of pyruvic acid, pyruvate in the citric acid cycle. All genomes sequenced to date encode enzymes that use coenzyme A as a Substrate (chemistry), substrate, and around 4% of cellular enzymes use it (or a thioester) as a substrate. In humans, CoA biosynthesis requires cysteine, pantothenic acid, pantothenate (vitamin B5), and adenosine triphosphate (ATP). In acetyl-CoA, its acetyl form, coenzyme A is a highly versatile molecule, serving metabolic functions in both the Anabolism, anabolic and Catabolism, catabolic pathways. Acetyl-CoA is utilised in the post-translational regulation and allosteric regulation of pyruvate dehydrogenase and carboxylase to maintain and support the partition of Pyruvic acid, pyruvate synthesis and degradation. Discovery of structure Coenzyme A was ident ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amino Acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although over 500 amino acids exist in nature, by far the most important are the 22 α-amino acids incorporated into proteins. Only these 22 appear in the genetic code of life. Amino acids can be classified according to the locations of the core structural functional groups ( alpha- , beta- , gamma- amino acids, etc.); other categories relate to polarity, ionization, and side-chain group type ( aliphatic, acyclic, aromatic, polar, etc.). In the form of proteins, amino-acid '' residues'' form the second-largest component (water being the largest) of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis. It is thought that they played a key role in enabling life on Earth and its emergence. Amino acids are formally named by the IUPAC- IUBMB Joint Commi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Environment (biophysical)
The natural environment or natural world encompasses all biotic and abiotic things occurring naturally, meaning in this case not artificial. The term is most often applied to Earth or some parts of Earth. This environment encompasses the interaction of all living species, climate, weather and natural resources that affect human survival and economic activity. The concept of the ''natural environment'' can be distinguished as components: * Complete ecological units that function as natural systems without massive civilized human intervention, including all vegetation, microorganisms, soil, rocks, plateaus, mountains, the atmosphere and natural phenomena that occur within their boundaries and their nature. * Universal natural resources and physical phenomena that lack clear-cut boundaries, such as air, water and climate, as well as energy, radiation, electric charge and magnetism, not originating from civilized human actions. In contrast to the natural environment is the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peptide Bond
In organic chemistry, a peptide bond is an amide type of covalent chemical bond linking two consecutive alpha-amino acids from C1 (carbon number one) of one alpha-amino acid and N2 (nitrogen number two) of another, along a peptide or protein chain. It can also be called a eupeptide bond to distinguish it from an isopeptide bond, which is another type of amide bond between two amino acids. Synthesis When two amino acids form a '' dipeptide'' through a ''peptide bond'', it is a type of condensation reaction. In this kind of condensation, two amino acids approach each other, with the non-side chain (C1) carboxylic acid moiety of one coming near the non-side chain (N2) amino moiety of the other. One loses a hydrogen and oxygen from its carboxyl group (COOH) and the other loses a hydrogen from its amino group (NH2). This reaction produces a molecule of water (H2O) and two amino acids joined by a peptide bond (−CO−NH−). The two joined amino acids are called a dipeptide. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Dimer
In biochemistry, a protein dimer is a macromolecular complex or protein multimer, multimer formed by two protein monomers, or single proteins, which are usually Non-covalent interaction, non-covalently bound. Many macromolecules, such as proteins or nucleic acids, form dimers. The word ''dimer'' has roots meaning "two parts", ''wikt:di-#Prefix, di-'' + ''wikt:-mer#Suffix, -mer''. A protein dimer is a type of protein quaternary structure. A protein homodimer is formed by two identical proteins while a protein heterodimer is formed by two different proteins. Most protein dimers in biochemistry are not connected by covalent bonds. An example of a non-covalent heterodimer is the enzyme reverse transcriptase, which is composed of two different amino acid chains. An exception is dimers that are linked by disulfide bridges such as the homodimeric protein IKBKG, NEMO. Some proteins contain specialized domains to ensure dimerization (dimerization domains) and specificity. The G protein- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endoplasmic Reticulum
The endoplasmic reticulum (ER) is a part of a transportation system of the eukaryote, eukaryotic cell, and has many other important functions such as protein folding. The word endoplasmic means "within the cytoplasm", and reticulum is Latin for "little net". It is a type of organelle made up of two subunits – rough endoplasmic reticulum (RER), and smooth endoplasmic reticulum (SER). The endoplasmic reticulum is found in most eukaryotic cells and forms an interconnected network of flattened, membrane-enclosed sacs known as cisternae (in the RER), and tubular structures in the SER. The membranes of the ER are continuous with the outer nuclear membrane. The endoplasmic reticulum is not found in red blood cells, or spermatozoa. There are two types of ER that share many of the same proteins and engage in certain common activities such as the synthesis of certain lipids and cholesterol. Different types of Cell (biology), cells contain different ratios of the two types of ER dependin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytosol
The cytosol, also known as cytoplasmic matrix or groundplasm, is one of the liquids found inside cells ( intracellular fluid (ICF)). It is separated into compartments by membranes. For example, the mitochondrial matrix separates the mitochondrion into many compartments. In the eukaryotic cell, the cytosol is surrounded by the cell membrane and is part of the cytoplasm, which also comprises the mitochondria, plastids, and other organelles (but not their internal fluids and structures); the cell nucleus is separate. The cytosol is thus a liquid matrix around the organelles. In prokaryotes, most of the chemical reactions of metabolism take place in the cytosol, while a few take place in membranes or in the periplasmic space. In eukaryotes, while many metabolic pathways still occur in the cytosol, others take place within organelles. The cytosol is a complex mixture of substances dissolved in water. Although water forms the large majority of the cytosol, its structure and proper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenylpropanoid
The phenylpropanoids are a diverse family of organic compounds that are biosynthesized by plants from the amino acids phenylalanine and tyrosine in the shikimic acid pathway. Their name is derived from the six-carbon, aromatic phenyl group and the three-carbon propene tail of coumaric acid, which is the central intermediate in phenylpropanoid biosynthesis. From 4-Coumaroyl-CoA, 4-coumaroyl-CoA emanates the biosynthesis of myriad natural products including Monolignol, lignols (precursors to lignin and lignocellulose), flavonoids, isoflavonoids, coumarins, aurones, stilbenes, catechin, and phenylpropanoids. The coumaroyl component is produced from cinnamic acid. Phenylpropanoids are found throughout the plant kingdom, where they serve as essential components of a number of structural polymers, provide protection from ultraviolet light, defend against herbivores and pathogens, and also mediate plant-pollinator interactions as floral pigments and scent compounds. Hydroxycinnamic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-terminal
The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the amine group is bonded to the carboxylic group of another amino acid, making it a chain. That leaves a free carboxylic group at one end of the peptide, called the C-terminus, and a free amine group on the other end called the N-terminus. By convention, peptide sequences are written N-terminus to C-terminus, left to right (in LTR writing systems). This correlates the translation direction to the text direction, because when a protein is translated from messenger RNA, it is created from the N-terminus to the C-terminus, as amino acids are added to the carboxyl end of the protein. Chemistry Each amino acid has an amine group and a carboxylic group. Amino acids link to one another by peptide bonds which form through a dehydration reaction that j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiolase
Thiolases, also known as acetyl-coenzyme A acetyltransferases (ACAT), are enzymes which convert two units of acetyl-CoA to acetoacetyl CoA in the mevalonate pathway. Thiolases are ubiquitous enzymes that have key roles in many vital biochemical pathways, including the beta oxidation pathway of fatty acid degradation and various biosynthetic pathways. Members of the thiolase family can be divided into two broad categories: degradative thiolases (EC 2.3.1.16) and biosynthetic thiolases (EC 2.3.1.9). These two different types of thiolase are found both in eukaryotes and in prokaryotes: acetoacetyl-CoA thiolase (EC:2.3.1.9) and 3-ketoacyl-CoA thiolase (EC:2.3.1.16). 3-ketoacyl-CoA thiolase (also called thiolase I) has a broad chain-length specificity for its substrates and is involved in degradative pathways such as fatty acid beta-oxidation. Acetoacetyl-CoA thiolase (also called thiolase II) is specific for the thiolysis of acetoacetyl-CoA and involved in biosynthetic pathways ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Dimer
In biochemistry, a protein dimer is a macromolecular complex or protein multimer, multimer formed by two protein monomers, or single proteins, which are usually Non-covalent interaction, non-covalently bound. Many macromolecules, such as proteins or nucleic acids, form dimers. The word ''dimer'' has roots meaning "two parts", ''wikt:di-#Prefix, di-'' + ''wikt:-mer#Suffix, -mer''. A protein dimer is a type of protein quaternary structure. A protein homodimer is formed by two identical proteins while a protein heterodimer is formed by two different proteins. Most protein dimers in biochemistry are not connected by covalent bonds. An example of a non-covalent heterodimer is the enzyme reverse transcriptase, which is composed of two different amino acid chains. An exception is dimers that are linked by disulfide bridges such as the homodimeric protein IKBKG, NEMO. Some proteins contain specialized domains to ensure dimerization (dimerization domains) and specificity. The G protein- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
