Document Detail


SREA is involved in regulation of siderophore biosynthesis, utilization and uptake in Aspergillus nidulans.
MedLine Citation:
PMID:  11555288     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Under conditions of low iron availability, most fungi excrete siderophores in order to mobilize extracellular iron. We show that lack of the GATA-type transcription factor SREA in Aspergillus nidulans not only leads to derepression of siderophore biosynthesis but also to deregulation of siderophore-bound iron uptake and ornithine esterase expression. Furthermore, SREA deficiency causes increased accumulation of ferricrocin, the siderophore responsible for intracellular iron storage. In sreA deletion strains, extracellular siderophore production is derepressed but still regulated negatively by iron availability, indicating the presence of an additional iron-regulatory mechanism. In contrast, iron affects ferricrocin accumulation in a positive way, suggesting a protective role for this siderophore in detoxification of intracellular iron excess. The harmfulness of deregulated iron uptake in this mutant is demonstrated by increased expression of genes encoding the antioxidative enzymes catalase CATB and the superoxide dismutases SODA and SODB. It is noteworthy that iron starvation was found to repress catB expression in wild-type (wt) and SREA-deficient strains, consistent with catB being subject to SREA-independent iron regulation. Differential display led to the identification of putative SREA target genes amcA and mirA. The deduced MIRA amino acid sequence displays significant similarity to recently characterized siderophore permeases of Saccharomyces cerevisiae. amcA encodes a putative mitochondrial carrier for the siderophore precursor ornithine, indicating cross-regulation of siderophore and ornithine metabolism.
Authors:
H Oberegger; M Schoeser; I Zadra; B Abt; H Haas
Related Documents :
4055798 - Acquisition of iron from transferrin regulates reticulocyte heme synthesis.
8368838 - Degradation of nitrobenzene by a pseudomonas pseudoalcaligenes.
3933428 - The effect of chelating agents on the elemental composition of sarcoplasmic reticulum: ...
20484548 - Daily supplementation with iron plus folic acid, zinc, and their combination is not ass...
8039478 - Tiagabine: a novel drug with a gabaergic mechanism of action.
19002688 - Persistent normalization of serum levels of uric acid in a gouty patient after administ...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Molecular microbiology     Volume:  41     ISSN:  0950-382X     ISO Abbreviation:  Mol. Microbiol.     Publication Date:  2001 Sep 
Date Detail:
Created Date:  2001-09-13     Completed Date:  2002-02-11     Revised Date:  2009-12-11    
Medline Journal Info:
Nlm Unique ID:  8712028     Medline TA:  Mol Microbiol     Country:  England    
Other Details:
Languages:  eng     Pagination:  1077-89     Citation Subset:  IM    
Affiliation:
Department of Microbiology, Medical School, University of Innsbruck, Fritz-Pregl-Str. 3, A-6020 Innsbruck, Austria.
Data Bank Information
Bank Name/Acc. No.:
GENBANK/AY027563;  AY027565
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Amino Acid Sequence
Aspergillus nidulans / genetics,  growth & development,  metabolism*
Bacterial Proteins / chemistry,  genetics*,  metabolism
Carrier Proteins / chemistry,  genetics*,  metabolism
Cloning, Molecular
Esterases / metabolism
Ferrichrome / analogs & derivatives*,  metabolism
Fungal Proteins / chemistry,  genetics*,  metabolism
GATA Transcription Factors
Gene Expression Regulation, Fungal*
Iron / metabolism
Membrane Transport Proteins / chemistry,  genetics*,  metabolism
Mitochondrial Membrane Transport Proteins
Mitochondrial Proteins / chemistry,  genetics*,  metabolism
Molecular Sequence Data
Ornithine / metabolism
Repressor Proteins / genetics,  metabolism*
Sequence Alignment
Sequence Analysis, DNA
Siderophores / biosynthesis*,  metabolism*
Superoxide Dismutase / genetics,  metabolism
Chemical
Reg. No./Substance:
0/Bacterial Proteins; 0/Carrier Proteins; 0/Fungal Proteins; 0/GATA Transcription Factors; 0/MIRA protein, Emericella nidulans; 0/Membrane Transport Proteins; 0/Mitochondrial Membrane Transport Proteins; 0/Mitochondrial Proteins; 0/Repressor Proteins; 0/SREA protein, Aspergillus nidulans; 0/Siderophores; 0/SodB protein, Bacteria; 15630-64-5/Ferrichrome; 23086-46-6/ferricrocin; 7006-33-9/Ornithine; 7439-89-6/Iron; EC 1.15.1.1/Superoxide Dismutase; EC 3.1.-/Esterases

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


Previous Document:  The roles of mucD and alginate in the virulence of Pseudomonas aeruginosa in plants, nematodes and m...
Next Document:  The pleuromutilin drugs tiamulin and valnemulin bind to the RNA at the peptidyl transferase centre o...