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Teixobactin
Teixobactin () is a peptide-like secondary metabolite of some species of bacteria, that kills some gram-positive bacteria. It appears to belong to a new class of antibiotics, and harms bacteria by binding to lipid II and lipid III, important precursor molecules for forming the cell wall. Teixobactin was discovered using a new method of culturing bacteria in soil, which allowed researchers to grow a previously unculturable bacterium now named ''Eleftheria terrae'', which produces the antibiotic. Teixobactin was shown to kill ''Staphylococcus aureus'' and ''Mycobacterium tuberculosis''. History In January 2015, a collaboration of four institutes in the US and Germany together with two pharmaceutical companies, reported that they had isolated and characterized a new antibiotic, killing "without detectable resistance." Teixobactin was discovered by screening previously unculturable bacteria present in a sample of soil from "a grassy field in Maine," using the isolation chip (iChi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eleftheria Terrae
''Eleftheria terrae'' is a recently discovered Gram-negative bacterium. ''E. terrae'' is a temporary name for the organism, as it was only discovered in 2014 and is still undergoing scientific study. It was found to produce a previously unknown antibiotic named teixobactin. The discovery of ''E. terrae'' could represent a new age of antibiotics, as teixobactin is the first new antibiotic discovered since the synthetic era of the 1980s. Prior research has indicated that other uncultivable bacteria like ''E. terrae'' have potential in the development of new antimicrobial agents. Discovery As of 2015, an estimated 99% of bacterial species are uncultured and require advanced means, such as the iChip, to be isolated. ''E. terrae'' is one such bacterium affectionately named by scientists "microbial dark matter" cultivated by emerging scientific methods. A team from Novobiotic Pharmaceuticals led by L. Ling discovered ''Eleftheria terrae'' in the fall of 2014 in a field in Maine usi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NovoBiotic Pharmaceuticals
NovoBiotic Pharmaceuticals is a privately held, early-stage biotechnology company focused on the discovery and development of new drugs from natural sources. Early history and focus The company was founded in 2003 in Cambridge, MA (USA), by Northeastern University professors Kim Lewis and Slava Epstein. Lewis is the director of Northeastern’s Antimicrobial Discovery Center, while Epstein is on the faculty of the Department of Biology. Both Lewis and Epstein are paid consultants to this company. The focus of the company is on the discovery of new antibiotics and oncology drugs. Research and drug development The founders had led the development of new techniques to search for useful molecules produced by the untapped vast majority of soil and marine bacteria that cannot be initially cultured in the laboratory. They developed diffusion chambers ( isolation chips) to be embedded in natural settings to grow "uncultivable" microorganisms ''in situ'', so that they could then be ext ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isolation Chip
The Isolation chip (or ichip) is a method of culturing bacteria. Using regular methods, 99% of bacterial species are not able to be cultured as they do not grow in conditions made in a laboratory, a problem called the "Great Plate Count Anomaly". The ichip instead cultures bacterial species within its soil environment. The soil is diluted in molten agar and nutrients such that only a single cell, on average, grows in the ichip's small compartments or wells, hence the term "isolation". The chip is then enclosed in a semipermeable plastic membrane and buried back in the dirt to allow in nutrients not available in the lab. With this culturing method, about 50 to 60 percent of bacterial species are able to survive. Notably, the bacterial species ''Eleftheria terrae'', which makes the antibiotic teixobactin that has shown promise against many drug-resistant strains like methicillin-resistant ''Staphylococcus aureus'', was discovered using the ichip in 2015. In addition to antibiotics, it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Depsipeptide
A depsipeptide is a peptide in which one or more of its amide, -C(O)NHR-, groups are replaced by the corresponding ester, -C(O)OR, Many depsipeptides have both peptide and ester linkages. Elimination of the N–H group in a peptide structure results in a decrease of H-bonding capability, which is responsible for secondary structure and folding patterns of peptides, thus inducing structural deformation of the helix and b-sheet structures. Because of decreased resonance delocalization in esters relative to amides, depsipeptides have lower rotational barriers for cis-trans isomerization and therefore they have more flexible structures than their native analogs. They are mainly found in marine and microbial natural products. Depsipeptide natural products 222px, Enterochelin is a depsipeptide that is an iron-transporter. Several depsipeptides have been found to exhibit anti-cancer properties. A depsipeptide enzyme inhibitor includes romidepsin, a member of the bicyclic peptide class, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Degradation
Chemical decomposition, or chemical breakdown, is the process or effect of simplifying a single chemical entity (normal molecule, reaction intermediate, etc.) into two or more fragments. Chemical decomposition is usually regarded and defined as the exact opposite of chemical synthesis. In short, the chemical reaction in which two or more products are formed from a single reactant is called a decomposition reaction. The details of a decomposition process are not always well defined but some of the process is understood; much energy is needed to break bonds. Since all decomposition reactions break apart the bonds holding it together in order to produce into its simpler basic parts, the reactions would require some form of this energy in varying degrees. Because of this fundamental rule, it is known that most of these reactions are endothermic although exceptions do exist. The stability of a chemical compound is eventually limited when exposed to extreme environmental conditions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diastereomer
In stereochemistry, diastereomers (sometimes called diastereoisomers) are a type of stereoisomer. Diastereomers are defined as non-mirror image, non-identical stereoisomers. Hence, they occur when two or more stereoisomers of a compound have different configurations at one or more (but not all) of the equivalent (related) stereocenters and are not mirror images of each other. When two diastereoisomers differ from each other at only one stereocenter, they are epimers. Each stereocenter gives rise to two different configurations and thus typically increases the number of stereoisomers by a factor of two. Diastereomers differ from enantiomers in that the latter are pairs of stereoisomers that differ in all stereocenters and are therefore mirror images of one another. Enantiomers of a compound with more than one stereocenter are also diastereomers of the other stereoisomers of that compound that are not their mirror image (that is, excluding the opposing enantiomer). Diastereomers h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amino Acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha amino acids appear in the genetic code. Amino acids can be classified according to the locations of the core structural functional groups, as Alpha and beta carbon, alpha- , beta- , gamma- or delta- amino acids; other categories relate to Chemical polarity, polarity, ionization, and side chain group type (aliphatic, Open-chain compound, acyclic, aromatic, containing hydroxyl or sulfur, etc.). In the form of proteins, amino acid '' residues'' form the second-largest component (water being the largest) of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis. It is thought that they played a key role in enabling life ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid residue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Essex
Essex () is a county in the East of England. One of the home counties, it borders Suffolk and Cambridgeshire to the north, the North Sea to the east, Hertfordshire to the west, Kent across the estuary of the River Thames to the south, and Greater London to the south and south-west. There are three cities in Essex: Southend, Colchester and Chelmsford, in order of population. For the purposes of government statistics, Essex is placed in the East of England region. There are four definitions of the extent of Essex, the widest being the ancient county. Next, the largest is the former postal county, followed by the ceremonial county, with the smallest being the administrative county—the area administered by the County Council, which excludes the two unitary authorities of Thurrock and Southend-on-Sea. The ceremonial county occupies the eastern part of what was, during the Early Middle Ages, the Anglo-Saxon Kingdom of Essex. As well as rural areas and urban areas, it forms ... [...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] |
Macrocyclic
Macrocycles are often described as molecules and ions containing a ring of twelve or more atoms. Classical examples include the crown ethers, calixarenes, porphyrins, and cyclodextrins. Macrocycles describe a large, mature area of chemistry. Synthesis The formation of macrocycles by ring-closure is called macrocylization. Pioneering work was reported for studies on terpenoid macrocycles. The central challenge to macrocyclization is that ring-closing reactions do not favor the formation of large rings. Instead, small rings or polymers tend to form. This kinetic problem can be addressed by using high-dilution reactions, whereby intramolecular processes are favored relative to polymerizations. Some macrocyclizations are favored using template reactions. Templates are ions, molecules, surfaces etc. that bind and pre-organize compounds, guiding them toward formation of a particular ring size. The crown ethers are often generated in the presence of an alkali metal cation, whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
