Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0240066 (iron deficiency)
 7,156 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to overcome the defects of difficult gene operations in low-copy suicide plasmid pCVD442, Gateway technology was applied in the construction process of recombinant plasmid for gene knockout in this study. With this improved knockout system, we inactivated sitC gene, which is associated with iron transport in Shigella flexneri 2a strain 301, to yield the mutant, MTS. The functional detection of the mutant was performed at the level of culture medium, cell and animal experiment, respectively. The gene expression profiles were compared with DNA microarray between the mutant and the wild type under iron-restricted conditions. The results showed that MTS grew obviously less well than the wild-type strains in L broth containing 150 micromol/L iron chelator DIP (2,2'-dipyridyl). Addition of iron or manganese to the cultures stimulated the growth of MTS to wild-type levels in rich culture medium. In either the experiment on the ability of intracellular multiplication and cell-to-cell spread in HeLa and U937 cell lines, or the experiment on keratoconjunctivitis in guinea pigs, MTS showed no obvious changes in virulence compared with the parental strain Sf301. When 65 micromol/L DIP was added to the cultured HeLa cells, the ability of intracellular multiplication of MTS reduced about 51.6% as compared with that of Sf301. The analysis of expression profiles under iron-limited condition showed that MTS was more sensitive for the change of iron deficiency than Sf301. There are 106 more up-regulated genes in MTS than in wild-type strains, which are involved in membrane transportation, amino acid metabolism and uncategorized function genes, while down-regulated genes are mainly involved in energy and carbohydrate metabolism. Under low iron conditions, the expression levels of known iron-transport associated genes generally increased. Additionally, the number of these genes and their increase amplitude in MTS are more than those in Sf301. Together, these results confirmed that Sit iron-transport system is important for the growth of Shigella.
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PMID:Construction, detection and microarray analysis on the Shigella flexneri 2a sitC mutant. 1609 55

In this study, we constructed single mutants MTS-1, MTS-2 of IroN and ShuA gene and double mutant MTS of them in Shigella dysenteriae A1 strain 51197 by insert and absence. The functional detection of every mutant was performed at the level of culture medium and cell experiment. The gene expression profiles of the mutants and the wild-type strains under iron-enriched and iron-limited conditions were analyzed by the SD51197 whole genomic microarray. The results showed that all the mutants grew obviously less well than the wild-type strains in L broth appending iron chelator DIP. The addition of iron to the cultures can stimulate the growth of mutants back to wild-type levels. In either the experiments on the ability of intracellular multiplication or the cell-to-cell spread in HeLa and U937 cell lines, mutants showed no obvious change in virulence compared with the parental strain SD51197. However when DIP was added to the cultured HeLa cells, the ability of intracellular multiplication of MTS-1, MTS-2, MTS has reduced about 23.4%, 25.2%, 43.6% respectively. The analysis of expression profiles under the iron-limited condition showed that the mutants were more sensitive for the changes of iron deficiency than the wild-type strains, many genes have been altered. Up-regulated genes mainly involved genes of transcription, coenzyme metabolism, amino acid transport and metabolism, and unknown functional genes, while down-regulated genes mainly involved genes of energy and carbohydrate metabolism and unknown function genes; the expression levels of known iron-transport associated genes generally showed up-regulated. The results demonstrated that iron-transport associated genes IroN, ShuA were likely to have some effects on the virulence and growth of S. dysenteriae.
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PMID:Construction, detection and microarray analysis on Shigella dysenteriae a1 IroN, ShuA single, double mutants. 1685 94