Loading...
The sulfur carrier protein TusA has a pleiotropic role in Escherichia coli that also affects molybdenum cofactor biosynthesis.
Dahl, Jan-Ulrik Radon, Christin Bühning, Martin Nimtz, Manfred Leichert, Lars I Denis, Yann Jourlin-Castelli, Cécile Iobbi-Nivol, Chantal Méjean, Vincent Leimkühler, Silke
Dahl, Jan-Ulrik
Radon, Christin
Bühning, Martin
Nimtz, Manfred
Leichert, Lars I
Denis, Yann
Jourlin-Castelli, Cécile
Iobbi-Nivol, Chantal
Méjean, Vincent
Leimkühler, Silke
Citations
Altmetric:
Advisors
Editors
Other Contributors
Issue Date
2013-02-22
Submitted date
Files
Loading...
original manuscript
Adobe PDF, 3.38 MB
Other Titles
Abstract
The Escherichia coli L-cysteine desulfurase IscS mobilizes sulfur from L-cysteine for the synthesis of several biomolecules such as iron-sulfur (FeS) clusters, molybdopterin, thiamin, lipoic acid, biotin, and the thiolation of tRNAs. The sulfur transfer from IscS to various biomolecules is mediated by different interaction partners (e.g. TusA for thiomodification of tRNAs, IscU for FeS cluster biogenesis, and ThiI for thiamine biosynthesis/tRNA thiolation), which bind at different sites of IscS. Transcriptomic and proteomic studies of a ΔtusA strain showed that the expression of genes of the moaABCDE operon coding for proteins involved in molybdenum cofactor biosynthesis is increased under aerobic and anaerobic conditions. Additionally, under anaerobic conditions the expression of genes encoding hydrogenase 3 and several molybdoenzymes such as nitrate reductase were also increased. On the contrary, the activity of all molydoenzymes analyzed was significantly reduced in the ΔtusA mutant. Characterization of the ΔtusA strain under aerobic conditions showed an overall low molybdopterin content and an accumulation of cyclic pyranopterin monophosphate. Under anaerobic conditions the activity of nitrate reductase was reduced by only 50%, showing that TusA is not essential for molybdenum cofactor biosynthesis. We present a model in which we propose that the direction of sulfur transfer for each sulfur-containing biomolecule is regulated by the availability of the interaction partner of IscS. We propose that in the absence of TusA, more IscS is available for FeS cluster biosynthesis and that the overproduction of FeS clusters leads to a modified expression of several genes.
Citation
The sulfur carrier protein TusA has a pleiotropic role in Escherichia coli that also affects molybdenum cofactor biosynthesis. 2013, 288 (8):5426-42 J. Biol. Chem.
Publisher
PubMed ID
PubMed Central ID
Additional Links
Embedded video
Type
Article
Language
en
Description
Series/Report no.
ISSN
1083-351X
EISSN
ISBN
ISMN
Gov't Doc #
Sponsors
License
Archived with thanks to The Journal of biological chemistry