UniProt Accession

 GSP_ECOLI; P0AES0; P43675; Q2M9K7 

Genbank Protein ID

 U23148; U28377; U00096; AP009048 

Genbank Nucleotide ID

 AAC43339.1; AAA69155.1; AAC76024.1; BAE77049.1 

Protein Name

 Bifunctional glutathionylspermidine synthetase/amidase 

Protein Synonyms/Alias

 GspSA; Glutathionylspermidine amidase; Gsp amidase; Glutathionylspermidine amidohydrolase [spermidine-forming]; Glutathionylspermidine synthetase; Gsp synthetase; Glutathione:spermidine ligase [ADP-forming]; Gsp synthase 

Gene Name

 gss 

Gene Synonyms/Alias

 gsp; b2988; JW2956 

Created Date

 July 27, 2013 

Organism

 Escherichia coli (strain K12) 

NCBI Taxa ID

 83333 

Lysine Modification

Position	Peptide	Type	References
122	GALLIWDKGGEFKDT	acetylation	[1]
127	WDKGGEFKDTGHVAI	acetylation	[1]
142	ITQLHGNKVRIAEQN	acetylation	[1]
225	NKGQFDGKWLDEKDP	acetylation	[1]
230	DGKWLDEKDPLQNAY	acetylation	[1]
280	MYLHATDKVLKDDNL	acetylation	[1]
283	HATDKVLKDDNLLAL	acetylation	[1]
388	FVHIMQDKDIEENYH	acetylation	[1]
527	TVNDELVKTGYAVKP	acetylation	[1]
555	HHEEVLDKTSGKFAE	acetylation	[1]
575	QQLWCLPKVDGKYIQ	acetylation	[1]
606	GDESLVIKKESDIEP	acetylation	[1]
607	DESLVIKKESDIEPL	acetylation	[1]
618	IEPLIVVKK******	acetylation	[1]

Reference

 [1] Acetyl-Phosphate Is a Critical Determinant of Lysine Acetylation in E. coli.
 Weinert BT, Iesmantavicius V, Wagner SA, Schölz C, Gummesson B, Beli P, Nyström T, Choudhary C.
 Mol Cell. 2013 Jul 25;51(2):265-72. [PMID: 23830618] 

Functional Description

 Catalyzes the formation of an amide bond between glutathione (GSH) and spermidine coupled with hydrolysis of ATP; also catalyzes the opposing reaction, i.e. the hydrolysis of glutathionylspermidine (Gsp) back to glutathione and spermidine. The amidase active site can also hydrolyze Gsp-disulfide (Gsp-S-S- Gsp) to Gsp-SG and Gsp S-thiolated proteins (GspSSPs) to GSH S- thiolated protein (GSSPs). Likely acts synergistically with glutaredoxin to regulate the redox environment of E.coli and defend against oxidative damage. In vitro, the amidase active site also catalyzes hydrolysis of amide and ester derivatives of glutathione (e.g. glutathione ethyl ester and glutathione amide) but lacks activity toward acetylspermidine (N1 and N8) and acetylspermine (N1). 

Sequence Annotation

 DOMAIN 34 176 Peptidase C51.
 NP_BIND 316 318 ATP.
 NP_BIND 539 540 ATP.
 NP_BIND 568 571 ATP.
 NP_BIND 603 605 ATP.
 REGION 2 195 Gsp amidase.
 REGION 78 81 Gsp binding.
 REGION 196 205 Linker.
 REGION 206 619 Gsp synthetase.
 ACT_SITE 59 59 Acyl-thioester intermediate; for amidase
 METAL 318 318 Magnesium 1.
 METAL 330 330 Magnesium 1.
 METAL 330 330 Magnesium 2.
 METAL 332 332 Magnesium 2.
 BINDING 58 58 Gsp.
 BINDING 64 64 Gsp.
 BINDING 149 149 Gsp.
 BINDING 316 316 Glutathione.
 BINDING 335 335 Glutathione.
 BINDING 391 391 Spermidine.
 BINDING 392 392 Glutathione.
 BINDING 446 446 Glutathione.
 BINDING 498 498 ATP.
 BINDING 533 533 ATP.
 BINDING 582 582 ATP.
 BINDING 610 610 Spermidine.
 MOD_RES 59 59 Cysteine sulfenic acid (-SOH); transient.  

Keyword

 3D-structure; ATP-binding; Complete proteome; Direct protein sequencing; Hydrolase; Ligase; Magnesium; Metal-binding; Multifunctional enzyme; Nucleotide-binding; Oxidation; Reference proteome. 

Sequence Source

 UniProt (SWISSPROT/TrEMBL); GenBank; EMBL 

Protein Length

 619 AA 

Protein Sequence

Gene Ontology

 GO:0005524; F:ATP binding; IEA:UniProtKB-KW.
 GO:0008884; F:glutathionylspermidine amidase activity; IDA:EcoCyc.
 GO:0008885; F:glutathionylspermidine synthase activity; IDA:EcoCyc.
 GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
 GO:0006749; P:glutathione metabolic process; IEA:UniProtKB-UniPathway.
 GO:0008216; P:spermidine metabolic process; IEA:UniProtKB-UniPathway. 

Interpro

 IPR007921; CHAP.
 IPR005494; GSPS_pre-ATP-grasp-like_dom.
 IPR016185; PreATP-grasp_dom. 

Pfam

 PF05257; CHAP
 PF03738; GSP_synth 

SMART

  

PROSITE

 PS50911; CHAP 

PRINTS