Cysteine is not the sulfur source for iron-sulfur cluster and methionine biosynthesis in the methanogenic archaeon Methanococcus maripaludis.
Summary of "Cysteine is not the sulfur source for iron-sulfur cluster and methionine biosynthesis in the methanogenic archaeon Methanococcus maripaludis."
Three multi-protein systems are known for iron-sulfur (Fe-S) cluster biogenesis in bacteria and eukaryotes: the NIF (nitrogen fixation), the ISC (iron-sulfur cluster), and the SUF (mobilization of sulfur) systems. In all three, cysteine is the physiological sulfur source, and the sulfur is transferred from cysteine desulfurase through a persulfidic intermediate to a scaffold protein. However, the biochemical nature of the sulfur source for Fe-S cluster assembly in archaea is not known, and many archaea lack homologs of cysteine desulfurases. Methanococcus maripaludis is a methanogenic archaeon that contains a high amount of protein-bound Fe-S clusters (45 nmol/mg protein). Cysteine in this archaeon is synthesized primarily via the tRNA-dependent SepRS/SepCysS pathway. When a DeltasepS mutant (a cysteine auxotroph) was grown with (34)S-labeled sulfide and unlabeled cysteine, < 8% of the cysteine, > 92% of the methionine, and > 87% of the sulfur in the Fe-S clusters in proteins was labeled, suggesting that the sulfur in methionine and Fe-S clusters was derived predominantly from exogenous sulfide instead of cysteine. Therefore, this investigation challenges the prior knowledge that cysteine is always the sulfur source for Fe-S cluster biosynthesis in vivo and suggests that Fe-S clusters are derived from sulfide in organisms living in sulfide-rich habitats.
University of Georgia, United States;
This article was published in the following journal.
Name: The Journal of biological chemistry
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/20709756
- DOI: http://dx.doi.org/10.1074/jbc.M110.152447
Medical and Biotech [MESH] Definitions
A class of iron-sulfur proteins that contains one iron coordinated to the sulfur atom of four cysteine residues. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
A group of proteins possessing only the iron-sulfur complex as the prosthetic group. These proteins participate in all major pathways of electron transport: photosynthesis, respiration, hydroxylation and bacterial hydrogen and nitrogen fixation.
Sulfur-sulfur Bond Isomerases
Enzymes that catalyze the transposition of a sulfur-sulfur bond. EC 5.3.4.
Sulfite Reductase (ferredoxin)
A FERREDOXIN-dependent oxidoreductase that is primarily found in PLANTS where it plays an important role in the assimilation of SULFUR atoms for the production of CYSTEINE and METHIONINE.
An element that is a member of the chalcogen family. It has an atomic symbol S, atomic number 16, and atomic weight 32.066. It is found in the amino acids cysteine and methionine.
Studies on sulfur metabolism in archaea have revealed many novel enzymes and pathways and have advanced our understanding on metabolic processes, not only of the archaea, but of biology in general. A...
Iron-sulfur cluster biosynthesis in Gram-positive bacteria is mediated by the SUF system. The transfer of sulfide from the cysteine desulfurase SufS to the scaffold protein SufU is one of the first st...
Assembly of iron-sulfur (Fe-S) clusters and maturation of Fe-S proteins in vivo require complex machineries. In Escherichia coli, under adverse stress conditions, this process is achieved by the SUF s...
Iron-sulfur clusters [Fe-S] are small, ubiquitous inorganic cofactors representing one of the earliest catalysts during biomolecule evolution and are involved in fundamental biological reactions inclu...
CyaY is the bacterial homolog of frataxin, proposed to be involved in the assembly of iron-sulfur clusters. While, the physiological iron donor for the iron-sulfur clusters assembly remains controvers...
Varied food intake, disease, and genetic differences result in complex diet-health interactions. In principle, information-rich metabolic analyses combined with bioinformatic tools provid...
The purpose of this study is to determine the level of sulfur amino acids in the diet that is needed to maintaining glutathione antioxidant status. This information could prove very usefu...
to assess the effect of Heliox with Noninvasive positive pressure ventilation to decrease dyspnea and improve physiologic and respiratory measures in patients with a previous exposure to S...
To compare, through a randomized, multicenter surgical trial, the postoperative tamponade effectiveness of intraocular silicone oil with that of an intraocular long-acting gas (initially s...
Availability of sulfur amino acids (SAA) is critical for glutathione/glutathione disulfide (GSH/GSSG) and cysteine/cystine (CYS/CYSS) redox in vivo and for many other physiologic functions...