This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Stuart, S J Articles by Luke, R K Search for Related Content PubMed PubMed Citation Articles by Stuart, S J Articles by Luke, R K

 Previous Article  |  Next Article 

J Bacteriol. 1980 July; 143(1): 35-42

Hydroxamate-mediated transport of iron controlled by ColV plasmids.

ABSTRACT

A new high-affinity system for iron transport, associated with the presence of ColV plasmids, has been detected in Escherichia coli and partially characterized. The presence of such "iron-transport plasmids" in E. coli cells that are defective in enterochelin-mediated transport of iron enabled them to grow in media to which 2,2'-dipyridyl had been added to reduce availability of iron. In addition, the presence of plasmid deoxyribonucleic acid in a mutant defective in enterochelin biosynthesis was associated with a marked increase in the rate of radioactive-iron uptake. Plasmid-determined uptake of iron was distinct from previously recognized systems for iron transport in E. coli K-12, and the colicin V molecule appeared not to be directly involved. Hydroxylamine-nitrogen could be detected in cell pellets of ColV+ cultures, and similar material was detected in supernatant fluids of late log- or stationary-phase cultures. The hydroxamate material was not detected in cell pellets or culture supernatants of strains from which plasmids had been eliminated, and a 95% decrease in hydroxamate synthesis was observed when cells were grown in minimal medium containing 2 microM iron.