RRC ID 35561
Author Dahl JU, Radon C, Bühning M, Nimtz M, Leichert LI, Denis Y, Jourlin-Castelli C, Iobbi-Nivol C, Méjean V, Leimkühler S.
Title The sulfur carrier protein TusA has a pleiotropic role in Escherichia coli that also affects molybdenum cofactor biosynthesis.
Journal J Biol Chem
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.
Volume 288(8)
Pages 5426-42
Published 2013-2-22
DOI 10.1074/jbc.M112.431569
PII S0021-9258(20)45046-X
PMID 23281480
PMC PMC3581435
MeSH Carbon-Sulfur Lyases / metabolism Coenzymes / biosynthesis* Electrophoresis, Gel, Two-Dimensional Escherichia coli / metabolism* Escherichia coli Proteins / metabolism* Gene Expression Regulation, Bacterial* Iron-Sulfur Proteins / metabolism Metalloproteins / biosynthesis* Models, Biological Molybdenum Cofactors Mutation Oligonucleotide Array Sequence Analysis / methods Pteridines RNA, Transfer / metabolism Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / methods Sulfhydryl Compounds / chemistry Sulfides / chemistry Sulfur / metabolism* Surface Plasmon Resonance / methods Transcription, Genetic
IF 4.238
Times Cited 34
WOS Category BIOCHEMISTRY & MOLECULAR BIOLOGY
Resource
Prokaryotes E. coli ME9062(BW25113 ) CV-49(MC4100)? JW3435-KC JW3307-KC JW1119-KC JW0764-KC JW0767-KC JW1994-KC JW1915-KC