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Teixobactin is a small molecule antibiotic that is active against 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. Its discovery was announced in early 2015 in the journal ''Nature''. Teixobactin was discovered using a new method of culturing bacteria in soil, which allowed researchers to grow a previously unculturable bacteria now named ''Eleftheria terrae'', which produces the antibiotic. In the ''Nature'' study, teixobactin was shown to kill ''Staphylococcus aureus'' or ''Mycobacterium tuberculosis ''without the bacteria developing resistance. == 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 iChip (isolation chip). The multiple independent iChip culture cells in a block of plastic are inoculated with soil diluted to deposit about one bacterium in each cell, and then sealed with semi-permeable membranes. The iChip is then planted in a box of the soil of origin. Nutrients and growth factors diffusing from the ambient soil into each culture cell through the membranes nurture growth of the bacterium into a colony that is then self-sustaining ''in vitro''. This arrangement allows growth of only one species in some of the cells. Tests for antibacterial activity against ''Staphylococcus aureus'' highlighted a previously undescribed bacterium which was named ''Eleftheria terrae''. It was found to be producing a new antibiotic compound that the researchers named teixobactin.〔 Its absolute stereochemistry was determined employing techniques that included chemical degradation with advanced Marfey’s analysis as well as partial degradation, synthesis of fragments obtained by degradation and the synthesis of all four diastereomers of an unusual amino acid not occurring in proteins. Teixobactin is the first novel antibiotic with drug potential isolated from bacteria in decades, and appears to represent a new class of antibiotics, raising hopes that the new isolation techniques employed could lead to further antibiotic discoveries.〔〔〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Teixobactin」の詳細全文を読む スポンサード リンク
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