Inhibitors of protein synthesis.

. Network
protein
synthesis inhibitorsaffect the protein biosynthetic substances are very many, they can act on
DNA
replication and RNA transcription, the protein biosynthetic indirect role, this section mainly discusses the inhibition of protein biosynthetic translation process blockers.(a)
Antibiotics class
blockers:Many antibiotics are designed to directly inhibit protein synthesis in bacterial cells with minimal side effects on the human body, they can act on all aspects of protein synthesis, including inhibition of starting factors, extension factors and the role of CYPs and so on.1, streptomycin, carnamycin, neomycin, etc.:these antibiotics belong to the base class, they mainly inhibit the three stages of Glominic negative bacterial protein synthesis:
(1) S starting compound formation, so that aminotyltRNA from the compound;
(2) misalide tRNA and mRNA in the extension phase of the peptide chain,
(3) in the termination phase, hinder the termination of the binding to the nucleoprotein body, so that the synthetic
peptide
chain can not be released, but also inhibit the 70S nuclear glycosome interlease.2, tycycline and tomycin: (1) acts on 30S sub-base in bacteria, inhibits the formation of the starting complex,
(2) inhibits the entry of ammonia tRNA into the A-bit of the nucleosome, blocks the extension of the peptide chain,
(3) affects the binding of termination factors with the RNA, so that the synthetic polypeptide chain can not shed the rnacide. In addition to inhibiting bacteria 70S cytosomes, tyrencline antibiotics also inhibit 80S cystics in human cells, but are more sensitive to 70S cystics, so they have a stronger inhibitory effect on bacterial protein synthesis.3, chlorampheniccin:a broad-spectrum antibiotic.
(1) chlorampheniccin and the A-bit on the nuclear glycogen closely binding, therefore hindering aminotyl tRNA into the A-bit,
(2) inhibits the activity of transpeptide enzymes, so that peptide chain extension is affected, bacterial protein can not be synthesized, so there is a more yo antibacterial effect.4, puromycinstructure is similar to tyrosine-tRNA, thus replacing some aminotin tRNA into the A bit of the nuclear glycogen, when the extended peptide into this abnormal A bit, easy to fall off, terminate the peptide chain synthesis. Because the translation process of cytomycin to the primary nucleus and the uterine organisms have interference, it is difficult to use as antibacterial drugs, some people try to use in tumor therapy.5, diphtheriadiphtheriaproduced by diphtheria is a protein synthesis inhibitor of etonocytes. Diphtheria mycomycin is actually a solution-derived phage β
gene
coded in the body of diphtheria, secreted by diphtheria transport, into
tissue
cells, its extension factor to the total nucleus - 2 (EF-2) co-price modification, the generation of EF-2 adenosine disphosphate kerucleose derivatives, so that EF-2 infested, its catalytic efficiency is very high, only a small amount can effectively inhibit the entire protein synthesis of cells, resulting in cell death.(ii) interferon inhibits the synthesis of viral proteinsinterferon is a small molecular protein that is synthesized and secreted by infected cells after a viral infection. From white blood cells α-interferon, from fibroblasts to β-interferon, in immune cells to γ-interferon.
interferons are combined into the membranes of uninfluented cells, inducing them to produce oligonucleotide synthase, nucleic acid incision enzymes, and protein
kinase
. These three enzymes are not synthesized when cells are not infected, and once infected with the virus, interferon or double-stranded RNA is present, they are activated and block the synthesis of viral proteins in different ways.
interferon and dsRNA activate protein kinases, protein kinases make the protein synthesis of the starting factor phosphate, make it inactivated, another way is mRNA degradation, interferon dsRNA activates 2,5 adenine oligonucleotide synthesis enzyme synthesis enzyme synthesis, 2,5 adenine oligonucleotides activate nucleic acid kerase, nucleic acid kerase water merime. because interferon has a strong antiviral effect, it is of great practical value in medicine, but the content of tissue is very small, it is difficult to separate interferon from biological tissue in large quantities. It is now difficult to apply genetically engineered synthetic interferons to meet the needs of research and clinical applications. small protein molecules are connected by
amino acids
through peptide bonds, and this connection within cells must be done by a cycle of the nucleoprotein body. mRNA carries genetic information about the sequence of amino acids in synthetic protein molecules. This is embodied by a password for every three bases, with a total of 64 codes.
the UAA, UAG, UGA representative termination signal, AUG represents not only the starting signal, but also methionine. tRNA carries specific amino acids, and its anticoencides identify the cocoons on mRNA, and the amino acids that bind to the bits on the RNA form peptide bonds under the influence of transpeptide enzymes. amino acids that are used to synthesize protein molecules must first bind to specific tRNAs under the specific aminoline tRNA synthesis enzyme, forming aminotRNA, which is the activity of amino acids. The starting stage of the nuclear protein cycle, first of all, the formation of a starting factor, GTP, mRNA and large and small sub-base composition of the 70S starting complex, peptide chain extension, every time into an amino acid, press the position, transpeptide, shedding, displacement, repeat these four steps. At the end of
, with the participation of the termination factor, transpeptide enzymes hydrolyzed the synthesized peptide chain away from the rnabus, and the nucleoprotein body also fell off from the mRNA and re-entered another cycle, when the protein was synthesized, on one mRNA chain, combining multiple RNA bodies at the same time, while synthesized the same polypeptide chain. protein synthesis also has many processing and modification processes, cutting part of the peptide segment, adding sugar, fat, phosphorylation, hydroxylation and so on. Proteins made up of poly polymers also go through a polymerization process. protein synthesis blockers, the action site is also different, the use of these theories, for the development of a variety of antibiotics is of great significance. the characteristics 1, genetic code table? 2, the main composition and working principle of the nucleoprotein body? 3, aminotyl tRNA synthase characteristics? the formation process of the starting complex when the peptide chain is synthesized. 5, the main similarity between the synthesis of proteins of the uterine and primary nuclear organisms. 6, the structural characteristics of secreted proteins and how the secretion process after processing is carried out.
.
.