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Synthesis of lipid
Lipid synthesis describes the processes that convert nutrient-derived carbons into FAs. The first step Involved in FA and cholesterol biosynthesis is the production of two-carbon units in the form of acetyl-CoA. Acetyl-CoA is generated from citrate by the enzyme ATP-citrate lipase (ACLY) and then converted to malonyl-CoA by the enzyme acetyl-CoA carboxylase (ACC) (Fig. 1). Acetyl-CoA and malonyl-CoA are then coupled to the acyl-carrier protein domain of the multifunctional enzyme fatty acid synthase (FASN). Repeated condensations of acetyl groups generate a basic 16-carbon saturated FA: palmitic acid. Palmitic acid Is further elongated and desaturases to generate the diverse spectrum of saturated and unsaturated FAs synthesized by mammalian cells. One of the main desaturases in mammalian cells is stearoyl-CoA desaturase (SCD), which introduces a double bond at the Δ9 position of palmitic and stearic acid to generate monounsaturated FAs. However, it should be noted that humans are not able to generate FAs that are unsaturated in the ω-3 or ω-6 position of the acyl chain. These essentIal FAs, α-linolenic acid and linoleic acid, need to be obtained from the diet.
Carbohydrates synthesis
Carbohydrate synthesis Is a sub-field of organic chemistry concerned with generating complex carbohydrate structures from simple units (monosaccharides) through natural or unnatural processes. The generation of carbohydrate structures Involves linking glycosyl groups like monosaccharides or oligosaccharides through glycosidic bonds is called glycosylation. Carbohydrate synthesis aims to generate the polysaccharides with controlled structures through atomically economic methods. Therefore, It is Important to construct glycosidic linkages that have optimum molecular geometry (stereos electivity) and the stable bond (regioselectivity) at the reaction site (isomeric canter).
Protein synthesis
Protein biosynthesis (or protein synthesis) is a core biological process, occurring inside cells, balancing the loss of cellular proteins (via degradation or export) through the production of new proteins. Proteins perform a number of critical functions as enzymes, structural proteins or hormones. Protein synthesis is a very similar process for both prokaryotes and eukaryotes but there are some distinct differ.Protein synthesis can be divided broadly into two phases: transcription and translation. During transcription, a section of DNA encoding a protein, known as a gene, Is converted Into a template molecule called messenger RNA (mRNA). This conversion is carried out by enzymes, known as RNA polymerases, In the nucleus of the cell. In eukaryotes, this mRNA Is initially produced in a premature form (pre-mRNA) which undergoes post-transcriptional modifications to produce mature mRNA. The mature mRNA is exported from the cell nucleus vIa nuclear pores to the cytoplasm of the cell for translation to occur. During translation, the mRNA is read by ribosomes which use the nucleotide sequence of the mRNA to determine the sequence of amino acids. The ribosomes catalyze the formation of covalent peptide bonds between the encoded amino acids to form a polypeptide chain.[citation needed]
Following translation the polypeptide chain must fold to form a functional protein; for example, to function as an enzyme the polypeptide chain must fold correctly to produce a functional active site. To adopt a functional three-dimensional shape, the polypeptide chain must first form a series of smaller underlying structures called secondary structures. The polypeptide chain In these secondary structures then folds to produce the overall 3D tertiary structure. Once correctly folded, the protein can undergo further maturation through different post-translational modifications, which can alter the protein's ability to function, its location within the cell (e.g. cytoplasm or nucleus) and its ability to interact with other proteins.
Protein biosynthesis has a key role in disease as changes and errors in this process, through underlying DNA mutations or protein misfielding, are often the underlying causes of a disease. DNA 1q22mutations change the subsequent mRNA sequence, which then alters the mRNA encoded amino acid sequence. Mutations can cause the polypeptide chain to be shorter by generating a stop sequence which causes early termination of translation. Alternatively, a mutation in the mRNA sequence changes the specific amino acid encoded at that position in the polypeptide chain. This amino acid change can impact the protein's ability to function or to fold correctly. Misfolded proteins have a tendency to form dense protein clumps, which are often implicated in diseases, particularly neurological disorders including Alzheimer's and Parkinson's disease.
Nucleic acid synthesis
Nucleic acids are large biomolecules that are crucial in all cells and viruses. They are composed of nucleotides, which are the monomer components: a 5-carbon sugar, a phosphate group and a nitrogenous base. The two main classes of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). If the sugar is ribose, the polymer Is RNA; if the sugar Is deoxyribose, a variant of ribose, the polymer is DNA.
Nucleic acids are chemical compounds that are found in nature. They carry information In cells and make up genetic material. These acids are very common In all living things, where they create, encode, and store information In every living cell of every life-form on Earth. In turn, they send and express that Information inside and outside the..
cell nucleus. From the Inner workings of the cell to the young of a living thing, they contain and provide Information via the nucleic acid sequence. This gives the RNA and DNA their unmistakable 'ladder-step' order of nucleotides within their molecules. Both play a crucial role in directing protein synthesis.
Strings of nucleotides are bonded to form spiraling backbones and assembled into chains of bases or base-pairs selected from the five primary, or canonical, nucleobases. RNA usually forms a chain of single bases, whereas DNA forms a chain of base pairs. The bases found in RNA and DNA are: adenine, cytosine, guanine, thymine, and uracil. Thymine occurs only In DNA and uracil only In RNA. Using amino acids and protein synthesis, the specific sequence in DNA of these nucleobase-pairs helps to keep and send coded instructions as genes. In RNA, base-pair sequencing helps to make new proteins that determine most chemical processes of all life forms.