Heterotrophic Metabolism of the Chemolithotroph Thiobacillus ferrooxidans
| العنوان: | Heterotrophic Metabolism of the Chemolithotroph Thiobacillus ferrooxidans |
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| المؤلفون: | D. G. Lundgren, Robert Tabita |
| المصدر: | Journal of Bacteriology. 108:334-342 |
| بيانات النشر: | American Society for Microbiology, 1971. |
| سنة النشر: | 1971 |
| مصطلحات موضوعية: | Iron, Physiology and Metabolism, Citric Acid Cycle, Dehydrogenase, Glucosephosphate Dehydrogenase, Nicotinamide adenine dinucleotide, Gluconates, Microbiology, Phosphates, chemistry.chemical_compound, Fumarates, Citrates, Molecular Biology, Hydro-Lyases, Aldehyde-Lyases, Carbon Isotopes, Pentosephosphates, Cell-Free System, biology, Phosphogluconate Dehydrogenase, Aldolase A, Fructosephosphates, Fructose, Metabolism, Carbon Dioxide, Thiobacillus, Isocitrate Dehydrogenase, Culture Media, Succinate Dehydrogenase, Citric acid cycle, Glucose, Models, Chemical, chemistry, Biochemistry, Spectrophotometry, biology.protein, Ketoglutaric Acids, NAD+ kinase, Oxidoreductases, NADP |
| الوصف: | Glucose-6-phosphate dehydrogenase and the enzymes of the Entner-Doudoroff pathway, 6-phosphogluconate dehydrase and 2-keto-3-deoxy-6-phosphogluconate aldolase (assayed together), are induced during heterotrophic growth of Thiobacillus ferrooxidans on an iron-glucose-supplemented medium or on glucose alone. By contrast, autotrophic cells (iron-grown) contain low levels of these enzymes. Fructose 1, 6-diphosphate aldolase, an enzyme of the Embden-Meyerhof pathway, is present at low levels irrespective of the growth medium, suggesting that this enzyme is not involved in energy-yielding reactions but merely provides intermediates for biosynthesis. The Entner-Doudoroff and pentose-phosphate pathways are the principle means through which glucose is dissimilated and is presumed to be concerned with energy production. Isotopic studies showed that a high rate of CO 2 formation from specifically labeled glucose came from carbon atoms 1 and 4. An unexpectedly high rate of evolution of CO 2 also came from carbon 6, suggesting that the triose phosphate formed during glucose breakdown and specifically as a result of 2-keto-3-deoxy-6-phosphogluconate aldolase activity, was metabolized via some unorthodox metabolic route. Cells grown in the iron-supplemented and glucose-salts media have a complete tricarboxylic acid cycle, whereas autotrophically grown T. ferrooxidans lacked both α-ketoglutarate dehydrogenase and reduced nicotinamide adenine dinucleotide oxidase. Two isocitrate dehydrogenases [nicotinamide adenine dinucleotide (NAD) and NAD phosphate (NADP) specific] were present. NAD-linked enzyme was constitutive, whereas the NADP-linked enzyme was induced upon adaptation of autotrophic cells to heterotrophic growth. |
| تدمد: | 1098-5530 0021-9193 |
| DOI: | 10.1128/jb.108.1.334-342.1971 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::5cb6b1ce42b271734dbf92f831b09133 https://doi.org/10.1128/jb.108.1.334-342.1971 |
| Rights: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....5cb6b1ce42b271734dbf92f831b09133 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 10985530 00219193 |
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| DOI: | 10.1128/jb.108.1.334-342.1971 |