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Protein Synthesis Inhibitors
A protein synthesis inhibitor is a compound that stops or slows the growth or proliferation of cells by disrupting the processes that lead directly to the generation of new proteins. While a broad interpretation of this definition could be used to describe nearly any compound depending on concentration, in practice, it usually refers to compounds that act at the molecular level on translational machinery (either the ribosome itself or the translation factor), taking advantages of the major differences between prokaryotic and eukaryotic ribosome structures. Mechanism In general, protein synthesis inhibitors work at different stages of bacterial mRNA translation into proteins, like initiation, elongation (including aminoacyl tRNA entry, proofreading, peptidyl transfer, and bacterial translocation) and termination: Earlier stages * Rifamycin inhibits bacterial DNA transcription into mRNA by inhibiting DNA-dependent RNA polymerase by binding its beta-subunit. * alpha-Amanitin i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribosome MRNA Translation En
Ribosomes () are macromolecular machines, found within all cells, that perform biological protein synthesis (messenger RNA translation). Ribosomes link amino acids together in the order specified by the codons of messenger RNA molecules to form polypeptide chains. Ribosomes consist of two major components: the small and large ribosomal subunits. Each subunit consists of one or more ribosomal RNA molecules and many ribosomal proteins (). The ribosomes and associated molecules are also known as the ''translational apparatus''. Overview The sequence of DNA that encodes the sequence of the amino acids in a protein is transcribed into a messenger RNA (mRNA) chain. Ribosomes bind to the messenger RNA molecules and use the RNA's sequence of nucleotides to determine the sequence of amino acids needed to generate a protein. Amino acids are selected and carried to the ribosome by transfer RNA (tRNA) molecules, which enter the ribosome and bind to the messenger RNA chain via an anticodo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tigecycline
Tigecycline, sold under the brand name Tygacil, is a tetracycline antibiotic medication for a number of bacterial infections. It is a glycylcycline class drug that is administered intravenously. It was developed in response to the growing rate of antibiotic resistant bacteria such as ''Staphylococcus aureus'', ''Acinetobacter baumannii'', and '' E. coli''. As a tetracycline derivative antibiotic, its structural modifications has expanded its therapeutic activity to include Gram-positive and Gram-negative organisms, including those of multi-drug resistance. It was given a U.S. Food and Drug Administration (FDA) fast-track approval and was approved on 17 June 2005. It was approved for medical use in the European Union in April 2006. It was removed from the World Health Organization's List of Essential Medicines in 2019. The World Health Organization classifies tigecycline as critically important for human medicine. Medical uses Antibacterial use Tigecycline is used to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fusidic Acid
Fusidic acid, sold under the brand name Fucidin among others, is a steroid antibiotic that is often used topically in creams or ointments and eyedrops but may also be given systemically as tablets or injections. , the global problem of advancing antimicrobial resistance has led to a renewed interest in its use. Medical uses Fusidic acid is active ''in vitro'' against ''Staphylococcus aureus'', most coagulase-positive staphylococci, Beta-hemolytic streptococci, ''Corynebacterium'' species, and most clostridium species. Fusidic acid has no known useful activity against enterococci or most Gram-negative bacteria (except Neisseria, Moraxella, ''Legionella pneumophila'', and '' Bacteroides fragilis''). Fusidic acid is active ''in vitro'' and clinically against ''Mycobacterium leprae'' but has only marginal activity against ''Mycobacterium tuberculosis''. One use of fusidic acid is its activity against methicillin-resistant ''Staphylococcus aureus'' (MRSA). Although many strai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aminoglycosides
Aminoglycoside is a medicinal chemistry, medicinal and bacteriology, bacteriologic category of traditional Gram-negative antibacterial medications that inhibit protein synthesis and contain as a portion of the molecule an amino-modified glycoside (sugar). The term can also refer more generally to any organic molecule that contains amino sugar substructures. Aminoglycoside antibiotics display bactericidal activity against Gram-negative aerobes and some anaerobic bacilli where resistance has not yet arisen but generally not against Gram-positive and anaerobic Gram-negative bacteria.ME Levison, MD, 2012, Aminoglycosides, The Merck Manua accessed 22 February 2014. Streptomycin is the first-in-class aminoglycoside antibiotic. It is derived from ''Streptomyces griseus'' and is the earliest modern agent used against tuberculosis. Streptomycin lacks the common 2-deoxystreptamine moiety (image right, below) present in most other members of this class. Other examples of aminoglycosides incl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clindamycin
Clindamycin is a lincosamide antibiotic medication used for the treatment of a number of bacterial infections, including osteomyelitis (bone) or joint infections, pelvic inflammatory disease, strep throat, pneumonia, acute otitis media (middle ear infections), and endocarditis. It can also be used to treat acne, and some cases of methicillin-resistant ''Staphylococcus aureus'' (MRSA). In combination with quinine, it can be used to treat malaria. It is available by mouth, by injection into a vein, and as a cream or a gel to be applied to the skin or in the vagina. Common side effects include nausea and vomiting, diarrhea, skin rashes, and pain at the site of injection. It increases the risk of hospital-acquired ''Clostridioides difficile'' colitis about fourfold and thus is only recommended for use when other antibiotics are not appropriate. It appears to be generally safe in pregnancy. It is of the lincosamide class and works by blocking bacteria from making protein. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrolide
Macrolides are a class of mostly natural products with a large macrocyclic lactone ring to which one or more deoxy sugars, usually cladinose and desosamine, may be attached. Macrolides belong to the polyketide class of natural products. Some macrolides have antibiotic or antifungal activity and are used as pharmaceutical drugs. Rapamycin is also a macrolide and was originally developed as an antifungal, but has since been used as an immunosuppressant drug and is being investigated as a potential longevity therapeutic. Macrolides are a diverse group with many members of very different properties: * Macrolides with 14-, 15-, or 16-membered rings and two attached sugar molecules are antibiotics that bind to bacterial ribosomes, the key representative being erythromycin. The term "macrolide antibiotics" tend to refer to just this class. * Some macrolides with very large (20+ membered) rings are immunosuppresants, the prototypical one being rapamycin. * Some 23-membered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trichothecene
Trichothecenes constitute a large group of chemically related mycotoxins. They are produced by Fungus, fungi of the genera ''Fusarium'', ''Myrothecium'', ''Trichoderma'', ''Podostroma'', ''Trichothecium'', ''Cephalosporium'', ', ''Stachybotrys'' (most in Hypocreales) and possibly others. Chemically, trichothecenes are a class of sesquiterpenes. All trichothecenes share the Cyclic compound, cyclic sesquiterpene structure but differ in the type of functional group attached to the carbon backbone. They are produced on many different grains such as wheat, Oat, oats, or maize by various ''Fusarium'' species including ''Gibberella zeae, F. graminearum'', ''Fusarium sporotrichioides, F. sporotrichioides'', ''F. poae,'' and ''Fusarium equiseti, F. equiseti''. Some moulds that produce trichothecene mycotoxins, such as ''Stachybotrys chartarum'', can grow in damp indoor environments. It has been found that macrocyclic trichothecenes produced by ''Stachybotrys chartarum, S. chartarum'' can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geneticin
G418 (geneticin) is an aminoglycoside antibiotic similar in structure to gentamicin B1. It is produced by '' Micromonospora rhodorangea''. G418 blocks polypeptide synthesis by inhibiting the elongation step in both prokaryotic and eukaryotic cells. Resistance to G418 is conferred by the neo gene from Tn5 encoding an aminoglycoside 3'-phosphotransferase, APT 3' II. G418 is an analog of neomycin sulfate, and has similar mechanism as neomycin. G418 is commonly used in laboratory research to select genetically engineered cells . In general, for bacteria and algae, concentrations of 5 μg/mL or less are used; for mammalian cells, concentrations of approximately 400 μg/mL are used for selection and 200 μg/mL for maintenance. However, optimal concentration for resistant clones selection in mammalian cells depends on the cell line used as well as on the plasmid carrying the resistance gene. Therefore, antibiotic titration should be done to find the best condition for ever ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polypeptide
Peptides are short chains of amino acids linked by peptide bonds. A polypeptide is a longer, continuous, unbranched peptide chain. Polypeptides that have a molecular mass of 10,000 Da or more are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. Peptides fall under the broad chemical classes of biological polymers and oligomers, alongside nucleic acids, oligosaccharides, polysaccharides, and others. Proteins consist of one or more polypeptides arranged in a biologically functional way, often bound to ligands such as coenzymes and cofactors, to another protein or other macromolecule such as DNA or RNA, or to complex macromolecular assemblies. Amino acids that have been incorporated into peptides are termed residues. A water molecule is released during formation of each amide bond.. All peptides except cyclic peptides have an N-terminal (amine group) and C-terminal (ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quinupristin/dalfopristin
Quinupristin/dalfopristin, or quinupristin-dalfopristin, (pronunciation: kwi NYOO pris tin / dal FOE pris tin) (trade name Synercid) is a combination of two antibiotics used to treat infections by staphylococci and by vancomycin-resistant ''Enterococcus faecium''. Quinupristin and dalfopristin are both streptogramin antibiotics, derived from pristinamycin. Quinupristin is derived from pristinamycin IA; dalfopristin from pristinamycin IIA. They are combined in a weight-to-weight ratio of 30% quinupristin to 70% dalfopristin. Discontinued 2022, there are no other manufacturers of this medication. Administration Intravenous, usually 7.5 mg/kg every 8 hours (infections/life threatening VRSA); every 12 hours (skin infections). No renal dosing adjustments, hepatic dosing adjustments are not defined, consider reducing dose. Mechanism of action Quinupristin and dalfopristin are protein synthesis inhibitors in a synergistic manner. While each of the two is only a bacteriostatic age ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptogramin
Streptogramins are a class of antibiotics. They work as protein synthesis inhibitors. Streptogramin A, Streptogramins are effective in the treatment of Vancomycin-resistant Staphylococcus aureus, vancomycin-resistant ''Staphylococcus aureus'' (VRSA) and Vancomycin-resistant Enterococcus, vancomycin-resistant ''Enterococcus'' (VRE), two of the most rapidly growing strains of multidrug-resistant bacteria. They fall into two groups: streptogramin A (23-membered macrolide) and streptogramin B (depsipeptide). The two groups act synergistically. They are naturally produced in a 3:7 ratio; most formulations keep this ratio. Members include: * Quinupristin/dalfopristin, made by chemically modifying pristinamycin (semisynthesis) * Pristinamycin, made by ''Streptomyces pristinaespiralis'' * Virginiamycin, made by ''Streptomyces virginiae'' and others * Linopristin/flopristin, made by semisynthesis. experimental streptogramin in clinical trials for the treatment of Respiratory system, respi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrolides
Macrolides are a class of mostly natural products with a large macrocycle, macrocyclic lactone ring to which one or more deoxy sugars, usually cladinose and desosamine, may be attached. Macrolides belong to the polyketide class of natural products. Some macrolides have antibiotic or antifungal activity and are used as pharmaceutical drugs. Rapamycin is also a macrolide and was originally developed as an antifungal, but has since been used as an immunosuppressant drug and is being investigated as a potential Life extension, longevity therapeutic. Macrolides are a diverse group with many members of very different properties: * Macrolides with 14-, 15-, or 16-membered rings and two attached sugar molecules are antibiotics that bind to bacterial ribosomes, the key representative being erythromycin. The term "macrolide antibiotics" tend to refer to just this class. * Some macrolides with very large (20+ membered) rings are immunosuppresants, the prototypical one being rapamycin. * S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
