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Sideromycin
Sideromycins are a group of antibiotics linked to siderophores by covalent bonds. Examples of naturally occurring sideromycins are albomycin and salmycin. Sideromycins have some unique merits as antibiotic. They can actively bypass permeability barriers (membranes) to deliver the drug inside the target bacterial cell, irrespective of the size and polarity of the antibiotic moiety contained into it. Most importantly as they are substrates of high affinity siderophore Siderophores (Greek: "iron carrier") are small, high-affinity iron- chelating compounds that are secreted by microorganisms such as bacteria and fungi. They help the organism accumulate iron. Although a widening range of siderophore functions is n ... transport systems they can be effective to kill bacteria at very low concentration. Also the delivery of the antibiotic will be highly target specific, so wouldn't affect the host system. Sideromycins is being considered as a new microbe-selective antibacterial agent, whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albomycin δ2-iron Bound
Albomycins are a group of naturally occurring antibiotics belonging to the class of sideromycins, which are "compounds composed of iron carriers called siderophores linked to antibiotic moieties". They are particularly effective against Gram-negative bacteria of the family '' Enterobacteriaceae'' and few Gram-positive bacteria such s ''Streptococcus pneumoniae'', ''Bacillus subtilis'' and '' Staphylococcus aureus''. In 2000 a group of scientists from SmithKline Beecham Pharmaceuticals, UK reported that the antibiotic part of albomycin ''in vitro'' can inhibit seryl t-RNA synthetase from both eukaryotic and prokaryotic representatives. Structure Albomycins are naturally occurring sideromycins produced by some streptomycetes. The siderophore part of albomycin δ2 is similar to ferrichrome. It contains three molecules of δ-N-hydroxy-δ-N-acetyl ornithine linked to a serine, all by peptide linkage. The C-terminus of the serine is linked to another serine attached to the antibi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antibiotics
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of such infections. They may either kill or inhibit the growth of bacteria. A limited number of antibiotics also possess antiprotozoal activity. Antibiotics are not effective against viruses such as the common cold or influenza; drugs which inhibit viruses are termed antiviral drugs or antivirals rather than antibiotics. Sometimes, the term ''antibiotic''—literally "opposing life", from the Greek roots ἀντι ''anti'', "against" and βίος ''bios'', "life"—is broadly used to refer to any substance used against microbes, but in the usual medical usage, antibiotics (such as penicillin) are those produced naturally (by one microorganism fighting another), whereas non-antibiotic antibacterials (such as sulfonamides and antisep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siderophore
Siderophores (Greek: "iron carrier") are small, high-affinity iron-chelating compounds that are secreted by microorganisms such as bacteria and fungi. They help the organism accumulate iron. Although a widening range of siderophore functions is now being appreciated. Siderophores are among the strongest (highest affinity) Fe3+ binding agents known. Phytosiderophores are siderophores produced by plants. Scarcity of soluble iron Despite being one of the most abundant elements in the Earth's crust, iron is not readily bioavailable. In most aerobic environments, such as the soil or sea, iron exists in the ferric (Fe3+) state, which tends to form insoluble rust-like solids. To be effective, nutrients must not only be available, they must be soluble. Microbes release siderophores to scavenge iron from these mineral phases by formation of soluble Fe3+ complexes that can be taken up by active transport mechanisms. Many siderophores are nonribosomal peptides, although several are biosynthes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Covalent Bond
A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs. The stable balance of attractive and repulsive forces between atoms, when they share electrons, is known as covalent bonding. For many molecules, the sharing of electrons allows each atom to attain the equivalent of a full valence shell, corresponding to a stable electronic configuration. In organic chemistry, covalent bonding is much more common than ionic bonding. Covalent bonding also includes many kinds of interactions, including σ-bonding, π-bonding, metal-to-metal bonding, agostic interactions, bent bonds, three-center two-electron bonds and three-center four-electron bonds. The term ''covalent bond'' dates from 1939. The prefix ''co-'' means ''jointly, associated in action, partnered to a lesser degree, '' etc.; thus a "co-valent bond", in essence, means that the atoms share " valence", such a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albomycin
Albomycins are a group of naturally occurring antibiotics belonging to the class of sideromycins, which are "compounds composed of iron carriers called siderophores linked to antibiotic moieties". They are particularly effective against Gram-negative bacteria of the family '' Enterobacteriaceae'' and few Gram-positive bacteria such s ''Streptococcus pneumoniae'', ''Bacillus subtilis'' and '' Staphylococcus aureus''. In 2000 a group of scientists from SmithKline Beecham Pharmaceuticals, UK reported that the antibiotic part of albomycin ''in vitro'' can inhibit seryl t-RNA synthetase from both eukaryotic and prokaryotic representatives. Structure Albomycins are naturally occurring sideromycins produced by some streptomycetes. The siderophore part of albomycin δ2 is similar to ferrichrome. It contains three molecules of δ-N-hydroxy-δ-N-acetyl ornithine linked to a serine, all by peptide linkage. The C-terminus of the serine is linked to another serine attached to the antibi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antibiotics
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of such infections. They may either kill or inhibit the growth of bacteria. A limited number of antibiotics also possess antiprotozoal activity. Antibiotics are not effective against viruses such as the common cold or influenza; drugs which inhibit viruses are termed antiviral drugs or antivirals rather than antibiotics. Sometimes, the term ''antibiotic''—literally "opposing life", from the Greek roots ἀντι ''anti'', "against" and βίος ''bios'', "life"—is broadly used to refer to any substance used against microbes, but in the usual medical usage, antibiotics (such as penicillin) are those produced naturally (by one microorganism fighting another), whereas non-antibiotic antibacterials (such as sulfonamides and antisep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
