|
Mutacin 1140
Mutacin 1140 is a bacteriocin produced by ''Streptococcus mutans''. It has activity against a broad spectrum of Gram-positive bacteria. It is a member of the class of compounds known as lantibiotics. Mutacin 1140 belongs to the epidermin subset of type Al lantibiotics. Molecules belonging to this family bind to lipid II which is a precursor to bacterial cell wall synthesis. While the effects mutacin 1140 has against gram-positive bacteria are known, it remains difficult to study due to it demonstrating poor pharmacokinetics. Besides the poor pharmacokinetics, it is easily vulnerable to proteolytic degradation by interfering with the protein's peptide bonds. References Lantibiotics Bacteriocins {{biochemistry-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteriocin
Bacteriocins are proteinaceous or peptidic toxins produced by bacteria to inhibit the growth of similar or closely related bacterial strain(s). They are similar to yeast and paramecium killing factors, and are structurally, functionally, and ecologically diverse. Applications of bacteriocins are being tested to assess their application as narrow-spectrum antibiotics. Bacteriocins were first discovered by André Gratia in 1925. He was involved in the process of searching for ways to kill bacteria, which also resulted in the development of antibiotics and the discovery of bacteriophage, all within a span of a few years. He called his first discovery a ''colicine'' because it killed '' E. coli.'' Classification Bacteriocins are categorized in several ways, including producing strain, common resistance mechanisms, and mechanism of killing. There are several large categories of bacteriocin which are only phenomenologically related. These include the bacteriocins from gram-po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptococcus Mutans
''Streptococcus mutans'' is a facultatively anaerobic, gram-positive coccus (round bacterium) commonly found in the human oral cavity and is a significant contributor to tooth decay. It is part of the "streptococci" (plural, non-italic lowercase), an informal general name for all species in the genus ''Streptococcus''. The microbe was first described by James Kilian Clarke in 1924. This bacterium, along with the closely related species '' Streptococcus sobrinus'', can cohabit the mouth: Both contribute to oral disease, and the expense of differentiating them in laboratory testing is often not clinically necessary. Therefore, for clinical purposes they are often considered together as a group, called the mutans streptococci (plural, non-italic due to its being an informal group name). This grouping of similar bacteria with similar tropism can also be seen in the viridans streptococci, another group of ''Streptococcus'' species. Ecology ''S. mutans'' is naturally present in the h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-positive
In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive bacteria take up the crystal violet stain used in the test, and then appear to be purple-coloured when seen through an optical microscope. This is because the thick peptidoglycan layer in the bacterial cell wall retains the stain after it is washed away from the rest of the sample, in the decolorization stage of the test. Conversely, gram-negative bacteria cannot retain the violet stain after the decolorization step; alcohol used in this stage degrades the outer membrane of gram-negative cells, making the cell wall more porous and incapable of retaining the crystal violet stain. Their peptidoglycan layer is much thinner and sandwiched between an inner cell membrane and a bacterial outer membrane, causing them to take up the counterstain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lantibiotics
Lantibiotics are a class of polycyclic peptide antibiotics that contain the characteristic thioether amino acids lanthionine or methyllanthionine, as well as the unsaturated amino acids dehydroalanine, and 2-aminoisobutyric acid. They belong to ribosomally synthesized and post-translationally modified peptides. Lanthionine is composed of two alanine residues that are crosslinked on their β-carbon atoms by a thioether (monosulfide) linkage. Lantibiotics are produced by a large number of Gram-positive bacteria such as '' Streptococcus'' and ''Streptomyces'' to attack other Gram-positive bacteria, and as such, they are considered a member of the bacteriocins. Bacteriocins are classified according to their extent of posttranslational modification. The lantibiotics are a class of more extensively modified bacteriocins, also called Class I bacteriocins. (Bacteriocins for which disulfide bonds are the only modification to the peptide are Class II bacteriocins.) Lantibiotics a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pharmacokinetics
Pharmacokinetics (from Ancient Greek ''pharmakon'' "drug" and ''kinetikos'' "moving, putting in motion"; see chemical kinetics), sometimes abbreviated as PK, is a branch of pharmacology dedicated to determining the fate of substances administered to a living organism. The substances of interest include any chemical xenobiotic such as: pharmaceutical drugs, pesticides, food additives, cosmetics, etc. It attempts to analyze chemical metabolism and to discover the fate of a chemical from the moment that it is administered up to the point at which it is completely eliminated from the body. Pharmacokinetics is the study of how an organism affects a drug, whereas pharmacodynamics (PD) is the study of how the drug affects the organism. Both together influence dosing, benefit, and adverse effects, as seen in PK/PD models. Overview Pharmacokinetics describes how the body affects a specific xenobiotic/chemical after administration through the mechanisms of absorption and distribut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lantibiotics
Lantibiotics are a class of polycyclic peptide antibiotics that contain the characteristic thioether amino acids lanthionine or methyllanthionine, as well as the unsaturated amino acids dehydroalanine, and 2-aminoisobutyric acid. They belong to ribosomally synthesized and post-translationally modified peptides. Lanthionine is composed of two alanine residues that are crosslinked on their β-carbon atoms by a thioether (monosulfide) linkage. Lantibiotics are produced by a large number of Gram-positive bacteria such as '' Streptococcus'' and ''Streptomyces'' to attack other Gram-positive bacteria, and as such, they are considered a member of the bacteriocins. Bacteriocins are classified according to their extent of posttranslational modification. The lantibiotics are a class of more extensively modified bacteriocins, also called Class I bacteriocins. (Bacteriocins for which disulfide bonds are the only modification to the peptide are Class II bacteriocins.) Lantibiotics a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
