| Autor: |
Chung, T D, Matzanke, B F, Winkelmann, G, Raymond, K N |
| Zdroj: |
Journal of Bacteriology; January 1986, Vol. 165 Issue: 1 p283-287, 5p |
| Abstrakt: |
Two partially resolved chromatographic fractions of geometrical and optical isomers of the chromic complexes of desferricoprogen, a siderophore from Neurospora crassa, were obtained from high-pressure liquid chromatography on a reverse-phase matrix. The first fraction was identified as a cis complex with a 20% diastereomeric excess of the lambda isomer. The second fraction was identified as a mixture of several of the possible trans isomers with a net 20% diastereomeric excess of the delta isomers. These fractions were used to evaluate the stereospecificity of the coprogen-mediated iron uptake system with respect to the metal coordination center. Fraction II competitively inhibited coprogen uptake, whereas fraction I showed only slight inhibition. N. crassa accumulated chromium from fraction II faster than the rate of chromium uptake from fraction I. Neither fraction had a significant effect on the uptake of ferricrocin, suggesting that coprogen and ferricrocin are taken up by different receptor systems. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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