共查询到20条相似文献,搜索用时 15 毫秒
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V. Braun 《Die Naturwissenschaften》1977,64(3):126-132
The resistance of mainly gram-negative bacteria against antibiotics is discussed with respect to new discoveries on the permeability barrier of the outer membrane. Proteins originally characterized as virus receptors have been found to be involved in the translocation of certain substrates across the membrane. Antibiotics can reach their target by the same “pores”. 相似文献
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Methanogenic bacteria area diverse group of anaerobic procaryotes that ferment CO2 plus H2 to CH4. Besides their unusual energy metabolism they are unique in that their cell walls do not contain murein, and in that their cell membranes are composed of isoprenoid lipids. Coenzymes occur which are not found in any other living organism. The translation apparatus differs, e.g., in not being affected by antibiotics known to be inhibitors of procaryotic protein synthesis. Most of the methanogens can grow on CO2 as sole carbon source; autotrophic CO2 fixation does not, however, proceed via reactions of the Calvin cycle. Molecular genealogical analysis has revealed that methanogenic bacteria constitute a grouping phylogenetically distinct from most other procaryotes. 相似文献
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Helmut Metzner 《Die Naturwissenschaften》1973,60(11):507-515
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Reinhard W. Kaplan 《Die Naturwissenschaften》1950,37(11):249-254
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Reinhard W. Kaplan 《Die Naturwissenschaften》1950,37(12):276-284
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Drei neue Nickelenzyme aus anaeroben Bakterien 总被引:2,自引:0,他引:2
Rudolf K. Thauer Astrid Brandis-Heep Gabriele Diekert Hans -Harald Gilles Ernst Günther Graf Rolf Jaenchen Peter Schönheit 《Die Naturwissenschaften》1983,70(2):60-64
Until recently nickel was not considered to be an element of biological importance. Nutritional studies have shown, however, that many eucaryotic and procaryotic organisms are dependent on the transition metal for growth. Four enzymes are presently known to contain nickel: urease from plants and from bacteria; methyl CoM reductase from methanogenic bacteria; all “uptake” hydrogenases investigated so far; and carbon monoxide dehydrogenase from anaerobic bacteria. The prosthetic group of the methyl CoM reductase has been identified as a nickel tetrapyrrole, the structure of which has been elucidated. 相似文献