Molybdopterin synthase sulfur carrier subunit MoaD [Coenzyme transport and metabolism]; Molybdopterin synthase sulfur carrier subunit MoaD is part of the Pathway/BioSystem: Molybdopterin biosynthesis

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gi 1738373873  4 TLLIPTALRAFTdGQGKVTLE---GHTVGQLVAALAARYPDIQPHLyddagaLRSFINLYVGEHNIKttggLETPVSDGA 80
Cdd:COG1977    3 TVRYFAALREAA-GKSEEEVElpeGATVGDLLEALAARYPGLAERL------LRRRVRVAVNGEDVR----LDTPLKDGD 71

                         90
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gi 1738373873 81 EVLLVPAIAGG 91
Cdd:COG1977   72 EVALFPPVAGG 82

ThiS family; ThiS (thiaminS) is a 66 aa protein involved in sulphur transfer. ThiS is coded in the thiCEFSGH operon in E. coli. This family of proteins have two conserved Glycines at the COOH terminus. Thiocarboxylate is formed at the last G in the activation process. Sulphur is transferred from ThiI to ThiS in a reaction catalyzed by IscS. MoaD, a protein involved sulphur transfer in molybdopterin synthesis, is about the same length and shows limited sequence similarity to ThiS. Both have the conserved GG at the COOH end.

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gi 1738373873  5 LLIPTALRAFTdGQGKVTLEGHTVGQLVAALAARYPdiqphlyddagALRSFINLYVGEHNIKTtGGLETPVSDGAEVLL 84
Cdd:pfam02597  1 VLLNAELRELA-GKDEELAEGATVAELLEALGLRYP-----------ELRERVAVAVNGEIVPR-LWLDTPLKDGDEVAI 67

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gi 1738373873 85 VPAIAGG 91
Cdd:pfam02597 68 IPPVGGG 74

ubiquitin-like (Ubl) domain found in a group of small sulfide carrier proteins; Ubiquitin-like (Ubl) domain found in a group of small sulfide carrier proteins This family includes ThiS, MoaD, CysO, QbsE, and their homologs, which are structurally homologous to ubiquitin (Ub) and may function as the sulfide donor for the biosynthesis of thiamin, molybdopterin, cysteine, thioquinolobactin, and other sulfur-containing natural products. Ub is a protein modifier in eukaryotes that is involved in various cellular processes, including transcriptional regulation, cell cycle control, and DNA repair. Ubiquitination is comprised of a cascade of E1, E2 and E3 enzymes that results in a covalent bond between the C-terminus of Ub and the epsilon-amino group of a substrate lysine. Like Ub, small sulfide carrier proteins in this family are adenylated at a diglycyl C-terminus by specific activating proteins. The adenylated C-terminus is subsequently converted to a thiocarboxylate, serving as the sulfide source. Those activating proteins are diverse and show little sequence similarity. This family also includes the small archaeal modifier protein (SAMP), including SAMP1, SAMP2 and SAMP3, which are Ub-like proteins that function as protein modifiers and are required for the production of sulfur-containing biomolecules in the archaeon Haloferax volcanii. SAMP1 and SAMP2 are involved in sulfur transfer during molybdenum cofactor biosynthesis and tRNA thiolation much like MoaD and Urm1, respectively. They can form covalent conjugates with their protein targets through an isopeptide linkage via their C-terminal diglycine motif in a streamlined archaeal E1-dependent pathway. SAMP2 also forms homo-conjugates through the intermolecular isopeptide bond between the C-terminal Gly and the Lys58 side chain, a feature that likely resembles polyubiquitination. SAMP3 conjugates are dependent on the Ub-activating E1 enzyme homolog of archaea (UbaA) for synthesis and are cleaved by the JAMM/MPN+ domain metalloprotease HvJAMM1.

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gi 1738373873  4 TLLIPTALRAFTDGQGKVTLEG-HTVGQLVAALAARYPDIQPHLyDDAGALRSFINLYVGEHNIKTTGGLeTPVSDGAEV 82
Cdd:cd17040    2 KVRLFGALREAGAGEEEIEVEGgTTVRDLLDALSERYPGLFEAL-DEDGELRPFILVFVNGRDVRLDDGL-TPLKDGDEV 79

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gi 1738373873 83 LLVPAIAGG 91
Cdd:cd17040   80 DILPPVAGG 88

MoaD family protein, archaeal; Members of this family appear to be archaeal versions of MoaD, subunit 1 of molybdopterin converting factor. This model has been split from the bacterial/eukaryotic equivalog model TIGR01682 because the presence of two members of this family in a substantial number of archaeal species suggests that roles might not be interchangeable. [Biosynthesis of cofactors, prosthetic groups, and carriers, Molybdopterin]

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gi 1738373873 20 KVTLEGHTVGQLVAALAARYPDIQPHLYDDAGALRSFINLYVGEHNIKttGGLETPVSDGAEVLLVPAIAGG 91
Cdd:TIGR01687 19 EIEIEGKTVGDLLNELMARYPKEFSELFKEGLGLVPNVIILVNGRNVD--WGLGTELKDGDVVAIFPPVSGG 88

ubiquitin-like (Ubl) domain found in small archaeal modifier protein 1 (SAMP1); Ubiquitin-like small archaeal modifier protein 1 (SAMP1) shows a beta-grasp fold of Ub, suggesting that this archaeal Ubl molecule is more closely related to eukaryotic Ub and Ubls than to its prokaryotic counterpart. Several Ub-like structural features such as an N-terminal single lysine residue and di-glycine motif at the C-terminus, spatially isolated, implicate formation of a poly-SAMPylated chainpoly-SAMPylation. SAMP1 can form covalent conjugates with its protein targets through an isopeptide linkage via their C-terminal diglycine motif in a streamlined archaeal E1-dependent pathway. It is involved in sulfur transfer during molybdenum cofactor biosynthesis much like MoaD. This family also includes proteins such as Thermoplasma acidophilum TA0895 and others, all closely related to proteins MoaD.

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gi 1738373873 21 VTLEGHTVGQLVAALAARYPDIQPHLYDDAGALRSFINLYVGEHNIKTTGGLETPVSDGAEVLLVPAIAGG 91
Cdd:cd17505   20 LDVDGATVGEVLDSLVALYPALEGRLITEDGELAEHVIVLVNGRNIRHLEGLETPLKDGDTIDLFPPVAGG 90