| Autor: |
Langman L, Young IG, Frost GE, Rosenberg H, Gibson F |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of bacteriology [J Bacteriol] 1972 Dec; Vol. 112 (3), pp. 1142-9. |
| DOI: |
10.1128/jb.112.3.1142-1149.1972 |
| Abstrakt: |
Three mutant strains of Escherichia coli have been isolated which are lacking ferric-enterochelin esterase activity. This enzyme catalyzes the hydrolysis of the enterochelin moiety of ferric-enterochelin to yield ultimately three molecules of N-2,3-dihydroxybenzoylserine. The mutants (designated fes(-)) were shown to be unaffected in enterochelin biosynthesis, capable of enterochelin-mediated iron uptake, and able to utilize ferric-dihydroxybenzoylserine complexes normally. When grown under iron-deficient conditions, however, they showed an absolute requirement for added iron or citrate, a phenotype characteristic of mutants defective in some part of the enterochelin system of iron uptake. These results support the theory that iron, taken up by the cell as ferric-enterochelin is only available for general cell metabolism after hydrolysis of the ligand by enterochelin esterase. The three fes(-) strains were shown to be affected in the B component of enterochelin esterase. The fesB gene which is probably the structural gene coding for component B of the esterase, was shown to be located at about minute 14 on the E. coli chromosome together with seven other genes involved in the enterochelin system of iron transport. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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