In molecular biology, biosynthesis is a multi-step, enzyme-catalyzed process where substrates are converted into more complex products in living organisms. In biosynthesis, simple compounds are modified, converted into other compounds, or joined to form macromolecules. This process often consists of metabolic pathways. Some of these biosynthetic pathways are located within a single cellular organelle, while others involve enzymes that are located within multiple cellular organelles. Examples of these biosynthetic pathways include the production of lipid membrane components and nucleotides. Biosynthesis is usually synonymous with anabolism.
Methyltransferases are a large group of enzymes that all methylate their substrates but can be split into several subclasses based on their structural features. The most common class of methyltransferases is class I, all of which contain a Rossmann fold for binding S-Adenosyl methionine (SAM). Class II methyltransferases contain a SET domain, which are exemplified by SET domain histone methyltransferases, and class III methyltransferases, which are membrane associated. Methyltransferases can also be grouped as different types utilizing different substrates in methyl transfer reactions. These types include protein methyltransferases, DNA/RNA methyltransferases, natural product methyltransferases, and non-SAM dependent methyltransferases. SAM is the classical methyl donor for methyltransferases, however, examples of other methyl donors are seen in nature. The general mechanism for methyl transfer is a SN2-like nucleophilic attack where the methionine sulfur serves as the leaving group and the methyl group attached to it acts as the electrophile that transfers the methyl group to the enzyme substrate. SAM is converted to S-Adenosyl homocysteine (SAH) during this process. The breaking of the SAM-methyl bond and the formation of the substrate-methyl bond happen nearly simultaneously. These enzymatic reactions are found in many pathways and are implicated in genetic diseases, cancer, and metabolic diseases. Another type of methyl transfer is the radical S-Adenosyl methionine (SAM) which is the methylation of unactivated carbon atoms in primary metabolites, proteins, lipids, and RNA.
Cyclopropane fatty acids (CPA) are a subgroup of fatty acids that contain a cyclopropane group. Although they are usually rare, the seed oil from lychee contains nearly 40% CPAs in the form of triglycerides.
In biochemistry, fatty acid synthesis is the creation of fatty acids from acetyl-CoA and NADPH through the action of enzymes called fatty acid synthases. This process takes place in the cytoplasm of the cell. Most of the acetyl-CoA which is converted into fatty acids is derived from carbohydrates via the glycolytic pathway. The glycolytic pathway also provides the glycerol with which three fatty acids can combine to form triglycerides, the final product of the lipogenic process. When only two fatty acids combine with glycerol and the third alcohol group is phosphorylated with a group such as phosphatidylcholine, a phospholipid is formed. Phospholipids form the bulk of the lipid bilayers that make up cell membranes and surrounds the organelles within the cells.
In enzymology, a 3'-demethylstaurosporine O-methyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a 7-methylxanthosine synthase is an enzyme that catalyzes the chemical reaction
In enzymology, a caffeate O-methyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a fatty-acid O-methyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a hexaprenyldihydroxybenzoate methyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a loganate O-methyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a methionine S-methyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a methylene-fatty-acyl-phospholipid synthase is an enzyme that catalyzes the chemical reaction
In enzymology, a phosphatidyl-N-methylethanolamine N-methyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a putrescine N-methyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a theobromine synthase is an enzyme that catalyzes the chemical reaction
In enzymology, a tRNA (adenine-N1-)-methyltransferase (EC 2.1.1.36) is an enzyme that catalyzes the chemical reaction
In enzymology, a tRNA (guanine-N7-)-methyltransferase (EC 2.1.1.33) is an enzyme that catalyzes the chemical reaction
In enzymology, a tRNA (uracil-5-)-methyltransferase is an enzyme that catalyzes the chemical reaction
[Methionine synthase] reductase, or Methionine synthase reductase, encoded by the gene MTRR, is an enzyme that is responsible for the reduction of methionine synthase inside human body. This enzyme is crucial for maintaining the one carbon metabolism, specifically the folate cycle. The enzyme employs one coenzyme, flavoprotein.
Sterculic acid is a cyclopropene fatty acid. It is found in various plants of the genus Sterculia, including being the main component of Sterculia foetida seed oil.
