D4GZE7 · SAMP2_HALVD
- ProteinSmall archaeal modifier protein 2
- Genesamp2
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Functions as a protein modifier covalently attached to lysine residues of substrate proteins, as well as a sulfur carrier in tRNA thiolation. The protein modification process is termed sampylation and involves the formation of an isopeptide bond between the SAMP2 C-terminal glycine carboxylate and the epsilon-amino group of lysine residues on target proteins. Is able to form polymeric chains with itself at Lys-58, similar to ubiquitin and other ubiquitin-like proteins. May serve as a proteolytic signal in the cell to target proteins for degradation by proteasomes.
GO annotations
all annotations | all molecular function | virus receptor activity | dna binding | rna binding | cytoskeletal motor activity | catalytic activity | gtpase activity | structural molecule activity | transporter activity | cytoskeletal protein binding | lipid binding | cyclase activity | antioxidant activity | oxidoreductase activity | transferase activity | hydrolase activity | lyase activity | isomerase activity | ligase activity | protein tag activity | cargo receptor activity | histone binding | protein folding chaperone | translation regulator activity | nutrient reservoir activity | receptor ligand activity | molecular transducer activity | molecular adaptor activity | toxin activity | cell adhesion mediator activity | molecular function regulator activity | virus coreceptor activity | catalytic activity, acting on a protein | catalytic activity, acting on dna | catalytic activity, acting on rna | molecular carrier activity | transcription regulator activity | general transcription initiation factor activity | molecular sensor activity | molecular sequestering activity | atp-dependent activity | other molecular function | all biological process | mitotic cell cycle | cytokinesis | cytoplasmic translation | immune system process | muscle system process | circulatory system process | renal system process | respiratory system process | carbohydrate metabolic process | generation of precursor metabolites and energy | dna replication | dna repair | dna recombination | chromatin organization | dna-templated transcription | regulation of dna-templated transcription | trna metabolic process | protein folding | protein glycosylation | amino acid metabolic process | modified amino acid metabolic process | lipid metabolic process | vitamin metabolic process | sulfur compound metabolic process | intracellular protein transport | nucleocytoplasmic transport | autophagy | inflammatory response | mitochondrion organization | cytoskeleton organization | microtubule-based movement | peroxisome organization | lysosome organization | chromosome segregation | cell adhesion | establishment or maintenance of cell polarity | programmed cell death | photosynthesis | mrna metabolic process | snrna metabolic process | vesicle-mediated transport | reproductive process | digestive system process | signaling | cell differentiation | protein catabolic process | extracellular matrix organization | regulatory ncrna-mediated gene silencing | telomere organization | cell junction organization | wound healing | ribosome biogenesis | cilium organization | anatomical structure development | cell motility | nervous system process | endocrine process | protein maturation | transmembrane transport | nucleobase-containing small molecule metabolic process | hepaticobiliary system process | membrane organization | protein-containing complex assembly | cell wall organization or biogenesis | nitrogen cycle metabolic process | protein localization to plasma membrane | defense response to other organism | detoxification | meiotic nuclear division | mitotic nuclear division | mitochondrial gene expression | carbohydrate derivative metabolic process | other biological process | all cellular component | nuclear chromosome | extracellular region | extracellular space | cell wall | nucleus | nuclear envelope | nucleoplasm | chromosome | nucleolus | mitochondrion | lysosome | endosome | vacuole | peroxisome | endoplasmic reticulum | golgi apparatus | lipid droplet | microtubule organizing center | cytosol | ribosome | cytoskeleton | plasma membrane | cilium | plastid | thylakoid | external encapsulating structure | extracellular matrix | cytoplasmic vesicle | organelle | other cellular component | |||
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Aspect | Term | |
---|---|---|
Molecular Function | nucleotide binding | |
Molecular Function | protein tag activity | |
Biological Process | protein modification by small protein conjugation |
Keywords
- Biological process
- Ligand
Names & Taxonomy
Protein names
- Recommended nameSmall archaeal modifier protein 2
- Short namesSAMP2
- Alternative names
Gene names
Organism names
- Strain
- Taxonomic lineageArchaea > Euryarchaeota > Stenosarchaea group > Halobacteria > Halobacteriales > Haloferacaceae > Haloferax
Accessions
- Primary accessionD4GZE7
Proteomes
Phenotypes & Variants
Disruption phenotype
Cells lacking this gene grow similarly to wild-type in the presence of either DMSO or oxygen as the terminal electron acceptor, but are retarded in aerobic growth at 50 degrees Celsius. The lysine tRNAs of the mutant strain appear to be nonthiolated.
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Mutagenesis | 53 | Abolishes SAMPylation of substrate proteins. | ||||
Sequence: E → G | ||||||
Mutagenesis | 58 | Loss of isopeptide linkage of polymeric chains on NcsA; when associated with R-64. | ||||
Sequence: K → R | ||||||
Mutagenesis | 64 | Loss of isopeptide linkage of polymeric chains on NcsA; when associated with R-58. | ||||
Sequence: K → R | ||||||
Mutagenesis | 65-66 | Abolishes SAMPylation of substrate proteins. | ||||
Sequence: Missing |
PTM/Processing
Features
Showing features for chain, cross-link, modified residue.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000397102 | 1-66 | Small archaeal modifier protein 2 | |||
Sequence: MNVTVEVVGEETSEVAVDDDGTYADLVRAVDLSPHEVTVLVDGRPVPEDQSVEVDRVKVLRLIKGG | ||||||
Cross-link | 58 | Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in SAMP2) | ||||
Sequence: K | ||||||
Modified residue | 66 | 1-thioglycine; alternate | ||||
Sequence: G | ||||||
Modified residue | 66 | Glycyl adenylate; alternate | ||||
Sequence: G | ||||||
Cross-link | 66 | Glycyl lysine isopeptide (Gly-Lys) (interchain with K-? in acceptor proteins); alternate | ||||
Sequence: G |
Post-translational modification
The C-terminal glycine is likely acyl-adenylated (-COAMP) by UbaA, and also probably thiocarboxylated (-COSH) to function in sulfur transfer.
Keywords
- PTM
Proteomic databases
Structure
Sequence
- Sequence statusComplete
- Length66
- Mass (Da)7,118
- Last updated2010-05-18 v1
- Checksum09442B0B845C7DE0
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
CP001956 EMBL· GenBank· DDBJ | ADE03392.1 EMBL· GenBank· DDBJ | Genomic DNA |