Document Detail

Biochemical characterization of a Haemophilus influenzae periplasmic iron transport operon.
MedLine Citation:
PMID:  7559648     Owner:  NLM     Status:  MEDLINE    
Bacterial iron transport is critical for growth of pathogens in the host environment, where iron is limited as a form of nonspecific immunity. For Gram-negative bacteria such as Haemophilus influenzae, iron first must be transported across the outer membrane and into the periplasmic space, then from the periplasm to the cytosol. H. influenzae express a periplasmic iron-binding protein encoded by the hitA gene. This gene is organized as the first of a three-gene operon purported to encode a classic high affinity iron acquisition system that includes hitA, a cytoplasmic permease (hitB), and a nucleotide binding protein (hitC). In this study we describe the cloning, overexpression, and purification of the H. influenzae hitA gene product. The function of this protein is unambiguously assigned by demonstrating its ability to compete for iron bound to the chemical iron chelator 2,2'-dipyridyl, both in vitro and within the periplasmic space of a siderophore-deficient strain of Escherichia coli. Finally, the importance of a functional hitABC operon for iron acquisition is demonstrated by complementation of this siderophore-deficient E. coli to growth on dipyridyl-containing medium. These studies represent a detailed genetic, biochemical, and physiologic description of an active transport system that has evolved to efficiently transport iron and consequently is widely distributed among Gram-negative pathogenic bacteria.
P Adhikari; S D Kirby; A J Nowalk; K L Veraldi; A B Schryvers; T A Mietzner
Related Documents :
16315138 - Non-hfe hemochromatosis.
19493198 - Characterization of the orf1-tolqra operon in pseudomonas aeruginosa.
19529758 - Biofilm matrix regulation by candida albicans zap1.
11872468 - Functional genomics approach to identifying genes required for biofilm development by s...
24713688 - Microglia and brain macrophages in the molecular age: from origin to neuropsychiatric d...
1090588 - Isolation and characterization of d-serine deaminase constitutive mutants by utilizatio...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  The Journal of biological chemistry     Volume:  270     ISSN:  0021-9258     ISO Abbreviation:  J. Biol. Chem.     Publication Date:  1995 Oct 
Date Detail:
Created Date:  1995-11-21     Completed Date:  1995-11-21     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  2985121R     Medline TA:  J Biol Chem     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  25142-9     Citation Subset:  IM    
Department of Molecular Genetics and Biochemistry, University of Pittsburgh School of Medicine, Pennsylvania 15261, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Bacterial Proteins / physiology*
Base Sequence
Carrier Proteins / genetics,  isolation & purification,  physiology*
Cloning, Molecular
Escherichia coli / growth & development
Haemophilus influenzae / genetics,  metabolism*
Iron / metabolism*
Iron-Binding Proteins
Molecular Sequence Data
Receptors, Transferrin / metabolism
Recombinant Proteins / biosynthesis
Siderophores / deficiency
Transferrin-Binding Proteins
Grant Support
Reg. No./Substance:
0/Bacterial Proteins; 0/Carrier Proteins; 0/Iron-Binding Proteins; 0/Receptors, Transferrin; 0/Recombinant Proteins; 0/Siderophores; 0/Transferrin-Binding Proteins; 7439-89-6/Iron

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Low resolution X-ray structure of human methylamine-treated alpha 2-macroglobulin.
Next Document:  Expression of a Drosophila GATA transcription factor in multiple tissues in the developing embryos. ...