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Showing 1 to 18 of 18 for “"Auxotrophy"”.
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Fatty Acid Auxotrophy in Drosophila Larvae Lacking SREBP
A rapid increase in size is a major characteristic of larval development in Drosophila melanogaster. Such growth presumably requires the concomitant production of membrane lipids and is also accompanied by a significant accumulation of neutral lipid stores. Growing larvae must accumulate fatty …
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Molecular-genetic characterisation of arginine auxotrophy in the opportunistic human pathogen, Pseudomonas aeruginosa
… the SNP in ambA was responsible for the arginine auxotrophy bypass, and further investigation established that the SNP conferred change-of-function rather than loss-of-function to the AmbA protein. Detailed proteomic profiling of AMB128 revealed up-regulation of certain peptides derived from the …
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A METE mutant of Chlamydomonas reinhardtii provides new perspectives on the evolution of vitamin B12 auxotrophy
… an insight into the challenges of evolving B12 auxotrophy making it all the more remarkable that it is such a common trait.
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Investigating the genomic, transcriptomic and metabolic landscape of Chlamydomonas reinhardtii in the context of vitamin B12 availability
… cofactor. The phylogenetic distribution of B12 auxotrophy across the eukaryotic tree of life suggests that this trait has evolved multiple times in the algal kingdom, indicating that it has a selective advantage of some sort. Indeed, previous artificial evolution experiments alongside …
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Selection and optimization of gene targets for the metabolic engineering of E. coli
… and was unexpectedly found to exhibit oxygen auxotrophy. Expression of genes from Clostridium acetobutylicum resulted in production of 3-hydroxybutyric acid, but not butyric acid.
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Zur Erfassung trans-wirksamer Komponenten der Sauerstoff-abhängigen Gärungsregulation der Hefe Pichia stipitis
… was possible. As the introduction of the Ura3-auxotrophy into the transformation strain P. stipitis PJH53 his3-1 trp5-10 did not prove possible, neither by disruption of the gene, nor by crossing Ura3-auxotrophic strains, ScTRP5 was brought under the control of the PsADH2-promotor as a reporter …
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Impaired virulence factor production in a dihydroorotate dehydrogenase mutant (pyrD) of Pseudomonas aeruginosa.
… for the same connection between pyrimidine auxotrophy and pigment production applied in P. aeruginosa. To that end a knockout mutation was created in pyrD, the fourth step in the pyrimidine pathway which encodes dihydroorotate dehydrogenase. The resulting mutant required pyrimidines for …
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Studies on the improvement of lysine production in the genera Brevibacterium and Corynebacterium
… The combination of homnserine and leucine auxotrophy was found to be most effective in overcoming several of the control mechanisms present in the lysine biosynthetic pathway. Lysine production was increased approximately forty fold over the wild type B. lactofermentum. Lysine analogue …
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Isolation and characterization of a chitinase-secreting mutant of mortierella pusilla with altered interaction with the mycoparasite piptocephalis virginiana
… The particular morphology was not due to auxotrophy, because this strain displayed normal hyphae when glucose was used as the sole carbon source. One interesting phenomenon was that MUT23 showed an extensive clearing zone around the colony on colloidal chitin agar after 20-25 d. On the …
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Identification and characterization of a novel class of hydrogen peroxide targets in escherichia coli
… making it the most sensitive pathway known. This auxotrophy can be suppressed by adding shikimic acid, an intermediate in the common pathway for aromatic amino acid synthesis (the shikimic acid pathway), as well as Mn2+. I have found that the first enzyme in the shikimic acid pathway (DAHP …
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Superoxide stress in Escherichia coli
… could partially explain the aromatic amino acid auxotrophy of SOD- mutants. All four enzymes were purified and were demonstrated to be rapidly inactivated by O2- in vitro. The inactivation rate constants were comparable to those with which O2- reacts with [4Fe-4S] dehydratases. It was initially a …
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Biogenesis and Function of the Mitochondrial Ribosome
… severe mitochondrial deficiency, with uridine auxotrophy and disruption of assembly of small mitoribosomal subunit being the most striking effects observed. These findings provide further insight into the role of MRM1 in mitochondria and highlights the complexity of regulation of mitochondrial …
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Vitamin B12-mediated physiology, mutualisms, and gene regulation studies in Chlamydomonas reinhardtii and Phaeodactylum tricornutum
… the physiological consequences of vitamin auxotrophy, the B12 requirement and response characteristics were determined for growth, growth rate, cell size changes, and transcript response in vitamin deplete and replete conditions. The B12-dependent C. reinhardtii had a higher vitamin …
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Identification of cellular functions of cardiolipin as physiological modifiers of barth syndrome
… the RTG defect, crd1Δ cells exhibit glutamate auxotrophy at elevated temperature. We also find that overexpression of RTG2, a positive regulator of the RTG pathway, and deletion of BHM2, a negative regulator of the RTG pathway, rescues the ts phenotype of crd1Δ. The RTG pathway is required for …
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The First Insights into the Phylogeny, Genomics, and Ecology of the Novel Bacterial Phylum Armatimonadetes
… et al., 2011). Genetic mechanisms behind leucine auxotrophy and narrow pH growth range were also identified. These observations supported the theory that C. calidirosea T49T occupies the niche of a scavenger of diverse species of carbohydrates within geothermal environments, in association with …
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Identification of yeast genes involved in sauvignon blanc aroma development
… and Leu- yeast strain. It was shown that leucine auxotrophy most likely caused the Sec- phenotype. In a second F2 population of a cross between prototrophic Sec+ and Sec- strains, strong linkage was established to a region on chromosome 6 containing two candidate genes, DUG1 and IRC7. DUG1 was …
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Exploring B vitamin biosynthesis and exchange in understudied marine stramenopiles and their communities
… The results also demonstrate that B vitamin auxotrophy, in general, is more common in the heterotrophic species of the group than in the phototrophs. Finally, metagenomics was employed to probe the community surrounding an enigmatic marine stramenopile, Incisomonas marina, one of only a few …
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Studies on the regulation of nitrogen metabolism in clostridium acetobutylicum NCP 262 and clostridium beijerinckii NCIMB 8052
… of this organism which complemented glutamine auxotrophy in E. coli YMCll. The clone was sequenced and found to carry two complete and one incomplete ORF's which shared a high degree of nucleotide sequence similarity with ginA, ginR and gltA genes of C. acetobutylicum NCP 262 (87.8%, 86.5.% and …