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Sulfurtransferases
2010
Cell Biology of Molybdenum
Abstract The transition element molybdenum (Mo) is essential for (nearly) all biological systems as it is required by enzymes catalyzing diverse key reactions in the global carbon, sulfur,and nitrogen metabolism. The metal itself is biologically inactive unless it is complexed by a ...
2009
Mechanistic characterization of the sulfur-relay system for eukaryotic 2-thiouridine biogenesis at tRNA wobble positions
The wobble modification in tRNAs, 5-methoxycarbonylmethyl-2-thiouridine (mcm 5 s 2 U), is required for the proper decoding of NNR codons in eukaryotes. The 2-thio group confers conformational rigidity of mcm 5 s 2 U by largely fixing the C3'-endo ribose puckering, ensuring stable ...
Origin and function of ubiquitin-like proteins
Eukaryotic proteins can be modified through attachment to various small molecules and proteins. One such modification is conjugation to ubiquitin and ubiquitin-like proteins (UBLs), which controls an enormous range of physiological processes. Bound UBLs ...
2008
Molybdoproteomes and evolution of molybdenum utilization
The trace element molybdenum (Mo) is utilized in many life forms, and it is a key component of several enzymes involved in nitrogen, sulfur, and carbon metabolism. With the exception of nitrogenase, Mo is bound in proteins to a pterin, thus forming the molybdenum cofactor ( ...
Common thiolation mechanism in the biosynthesis of tRNA thiouridine and sulphur-containing cofactors
2-Thioribothymidine (s 2 T), a modified uridine, is found at position 54 in transfer RNAs (tRNAs) from several thermophiles; s 2 T stabilizes the L-shaped structure of tRNA and is essential for growth at higher temperatures. Here, we identified an ATPase (tRNA-two-thiouridine ...
The Sulfurtransferase Activity of Uba4 Presents a Link between Ubiquitin-like Protein Conjugation and Activation of Sulfur Carrier Proteins†
Because of mechanistic parallels in the activation of ubiquitin and the biosynthesis of several sulfur-containing cofactors, we have characterized the human Urm1 and Saccharomyces cerevisiae Uba4 proteins, which are very similar in sequence to MOCS2A and MOCS3, respectively, ...
Thio-modification of yeast cytosolic tRNA requires a ubiquitin-related system that resembles bacterial sulfur transfer systems
The wobble uridine in yeast cytosolic tRNA Lys2 UUU and tRNA Glu3 UUC undergoes a thio-modification at the second position (s 2 modification) and a methoxycarbonylmethyl modification at the fifth position (mcm 5 modification). We previously demonstrated that the cytosolic ...
An embarrassment of riches: the enzymology of RNA modification
The maturation of transfer RNA (tRNA) involves extensive chemical modification of the constituent nucleosides and results in the introduction of significant chemical diversity to tRNA. Many of the pathways to these modified nucleosides are characterized by chemically complex ...
A genome-wide screen identifies genes required for formation of the wobble nucleoside 5-methoxycarbonylmethyl-2-thiouridine in Saccharomyces cerevisiae
We recently showed that the γ-subunit of Kluyveromyces lactis killer toxin (γ-toxin) is a tRNA endonuclease that cleaves , , and 3′ of the wobble nucleoside 5-methoxycarbonylmethyl-2-thiouridine (mcm 5 s 2 U). The 5-methoxycarbonylmethyl ...
2007
Biosynthesis of the Thio-quinolobactin Siderophore: an Interesting Variation on Sulfur Transfer
Text: 15 Thio-quinolobactin, 8-hydroxy-4-methoxy-thioquinaldic acid (structure 1), is a 16 ... 17400.(10-12) The genes responsible for the biosynthesis of thio-quinolobactin have 18 ... There are a number of naturally occurring molecules of diverse structure that 27
A conserved modified wobble nucleoside (mcm5s2U) in lysyl-tRNA is required for viability in yeast
Transfer RNAs specific for Gln, Lys, and Glu from all organisms (except Mycoplasma) and organelles have a 2-thiouridine derivative (xm 5 s 2 U) as wobble nucleoside. These tRNAs read the A- and G-ending codons in the split codon boxes His/Gln, Asn/Lys, and Asp/Glu. In ...
2006
Crystal structure of Bacillus anthracis ThiI, a tRNA-modifying enzyme containing the predicted RNA-binding THUMP domain
ThiI is an enzyme responsible for the formation of the modified base S 4 U (4-thiouridine) found at position 8 in some prokaryotic tRNAs. This base acts as a sensitive trigger for the response mechanism to UV exposure, providing protection against its damaging effects. We ...
Trafficking in persulfides: delivering sulfur in biosynthetic pathways
The presence of sulfur in cofactors has been appreciated for over a century, but the trafficking and delivery of sulfur to cofactors and nucleosides is still not fully understood. In the last decade, great strides have been made toward understanding those processes and the ...
Cell biology of molybdenum
The transition element molybdenum (Mo) is of essential importance for (nearly) all biological systems as it is required by enzymes catalyzing diverse key reactions in the global carbon, sulfur and nitrogen metabolism. The metal itself is biologically inactive unless it is complexed by ...
The prokaryotic antecedents of the ubiquitin-signaling system and the early evolution of ubiquitin-like β-grasp domains
Ubiquitin (Ub)-mediated signaling is one of the hallmarks of all eukaryotes. Prokaryotic homologs of Ub (ThiS and MoaD) and E1 ligases have been studied in relation to sulfur incorporation reactions in thiamine and molybdenum/tungsten cofactor biosynthesis. However, there is no ...
Mechanistic insights into sulfur relay by multiple sulfur mediators involved in thiouridine biosynthesis at tRNA wobble positions
The wobble bases of bacterial tRNAs responsible for NNR codons are modified to 5-methylaminomethyl-2-thiouridine (mnm 5 s 2 U). 2-thio modification of mnm 5 s 2 U is required for accurate decoding and essential for normal cell growth. We identified five genes yhhP, ...
2005
Mitochondria-specific RNA-modifying enzymes responsible for the biosynthesis of the wobble base in mitochondrial tRNAs: implications for the molecular …
Human mitochondrial (mt) tRNA Lys has a taurine-containing modified uridine, 5-taurinomethyl-2-thiouridine ( m 5 s 2 U), at its anticodon wobble position. We previously found that the mt tRNA Lys , carrying the A8344G mutation from cells of patients with myoclonus ...
l-Cysteine Desulfidase: An [4Fe-4S] Enzyme Isolated from Methanocaldococcus jannaschii That Catalyzes the Breakdown of l-Cysteine into Pyruvate, Ammonia, and …
A [4Fe-4S] enzyme that decomposes l-cysteine to hydrogen sulfide, ammonia, and pyruvate has been isolated and characterized from Methanocaldococcus jannaschii. The sequence of the isolated enzyme demonstrated that the protein was the product of the M. jannaschii ...
Reconstitution of a new cysteine biosynthetic pathway in Mycobacterium tuberculosis
A new pathway for cysteine biosynthesis has been elucidated in Mycobacterium tuberculosis. This pathway involves a protein-bound thiocarboxylate (CysO−SH) as the sulfide donor, similar to thiamin biosynthesis. Cysteine synthase M (CysM) catalyzes the addition ...
2004
Evidence for the physiological role of a rhodanese-like protein for the biosynthesis of the molybdenum cofactor in humans
Recent studies have identified the human genes involved in the biosynthesis of the molybdenum cofactor. The human MOCS3 protein contains an N-terminal domain similar to the Escherichia coli MoeB protein and a C-terminal segment displaying similarities to the ...
Ubiquitin-proteasome system
Abstract. The capacity for exquisite regulation of ubiq- uitylation provides eukaryotic cells with a means to fine- tune both protein function and levels. This complex set of processes affects myriad proteins and potentially impacts all cellular processes. Ubiquitylation is brought about ...
2003
Attachment of the ubiquitin-related protein Urm1p to the antioxidant protein Ahp1p
Urm1p is a ubiquitin-related protein that serves as a posttranslational modification of other proteins. Urm1p conjugation has been implicated in the budding process and in nutrient sensing. Here, we have identified the first in vivo target for the urmylation pathway as the ...
2002
The rhodanese/Cdc25 phosphatase superfamily
... In this review, the rhodanese/Cdc25 phosphatase superfamily is analyzed. ... Figure 3 Neighbor-joining tree representing the rhodanese superfamily generated by CLUSTALW (correction for ... Catalytically active rhodanese and Cdc25 phosphatase domains The N- and C- ...
2001
A sulfurtransferase is required in the transfer of cysteine sulfur in the in vitro synthesis of molybdopterin from precursor Z in Escherichia coli
It has been shown that conversion of precursor Z to molybdopterin (MPT) by Escherichia coli MPT synthase entails the transfer of the sulfur atom of the C-terminal thiocarboxylate from the small subunit of the synthase to generate the dithiolene group of MPT and that the moeB ...
M ECHANISMS U NDERLYING U BIQUITINATION
Abstract The conjugation of ubiquitin to other cellular proteins regulates a broad range of eukaryotic cell functions. The high efficiency and exquisite selectivity of ubiquitination reactions reflect the properties of enzymes known as ubiquitin-protein ligases or E3s. An E3 recognizes its ...
2000
Evolution and function of ubiquitin-like protein-conjugation systems
Cellular proteins are frequently adorned with chemical modifications that alter their physical — and, as a result, their physiological — properties. Among the most spectacular of these molecular appendages are grafts of other proteins or even polymeric chains of other proteins. The ...
A protein conjugation system in yeast with homology to biosynthetic enzyme reaction of prokaryotes
Protein conjugation, such as ubiquitination, is the process by which the C-terminal glycine of a small modifier protein is covalently attached to target protein(s) through sequential reactions with an activating enzyme and conjugating enzymes. Here we report on a novel protein ...
1998
Cysteine Sulfinate Desulfinase, a NIFS-like Protein of Escherichia coli with Selenocysteine Lyase and Cysteine Desulfurase Activities: Gene Cloning, Purification and …
Page 1. Kyoto University KURENAI : Kyoto University Research Information Repository Title Cysteine Sulfinate Desulfinase, a NIFS-like Protein of Escherichia coli with Selenocysteine Lyase and Cysteine Desulfurase Activities ...
1997
Cysteine Sulfinate Desulfinase, a NIFS-like Protein ofEscherichia coli with Selenocysteine Lyase and Cysteine Desulfurase Activities
Selenocysteine lyase (EC 4.4.1.16) exclusively decomposes selenocysteine to alanine and elemental selenium, whereas cysteine desulfurase (NIFS protein) of Azotobacter vinelandii acts indiscriminately on both cysteine and selenocysteine to produce elemental sulfur and selenium ...
1991
Characteristics of Nicotiana tabacum nitrate reductase protein produced in Saccharomyces cerevisiae.
INTRODUCTION Tobacco nitrate reductase (NR) (EC 1.6.6.1) is a homodimeric enzyme that reduces nitrate to nitrite in the presence of NADH (NADH:NR activity). Each of its subunits contains three domains carrying respectively the prosthetic groups FAD, haem (cytochrome b-557) ...
UBA 1: an essential yeast gene encoding ubiquitin-activating enzyme.
The EMBO Journal vol.10 no.1 pp.227-236, 1991 ... UBA 1: an essential yeast gene encoding ubiquitin- ... John P.McGrath, Stefan Jentsch' and Alexander Varshavsky ... Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA 'Present ...
最終更新：2010年06月25日 17:57
