Open Accessfec B, a gene potentially involved in iron transport in Mycobacterium avium , is not induced within macrophages
Author(s) -
Wagner Dirk,
Sangari Felix J.,
Parker Amy,
Bermudez Luiz E.
Publication year - 2005
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1016/j.femsle.2005.05.005
Subject(s) - microbiology and biotechnology , escherichia coli , mycobacterium , biology , plasmid , shuttle vector , mycobacterium tuberculosis , phagosome , virulence , gene expression , gene , strain (injury) , bacteria , tuberculosis , biochemistry , genetics , recombinant dna , medicine , phagocytosis , pathology , anatomy , vector (molecular biology)
FecB is a protein involved in the transport of iron from ferric citrate in Escherichia coli and is present in the Mycobacterium tuberculosis genome sequence. Since the ability to retrieve iron from the host is crucial and may be related to virulence, we characterized the gene fec B from Mycobacterium avium , strain 101. An E. coli –mycobacterial shuttle plasmid with a fecB ‐promoter green fluorescence protein ( gfp )‐fusion was transformed into M. avium strain 104 to study the fec B‐regulation. In vitro, the fec B expression in M. avium weakly correlated with the amount of iron present in the medium but the expression was maximal when there was no iron in the culture medium. In macrophages, M. avium fec B was not induced during the early phase of infection, suggesting that the iron concentration in the mycobacterial phagosome is not sufficiently low to stimulate the expression of fec B in M. avium .