STRINGSTRING
STRING protein interaction network
Nodes:
Network nodes represent proteins
splice isoforms or post-translational modifications are collapsed, i.e. each node represents all the proteins produced by a single, protein-coding gene locus.
Node Color
colored nodes:
query proteins and first shell of interactors
white nodes:
second shell of interactors
Node Content
empty nodes:
proteins of unknown 3D structure
filled nodes:
a 3D structure is known or predicted
Edges:
Edges represent protein-protein associations
associations are meant to be specific and meaningful, i.e. proteins jointly contribute to a shared function; this does not necessarily mean they are physically binding to each other.
Known Interactions
from curated databases
experimentally determined
Predicted Interactions
gene neighborhood
gene fusions
gene co-occurrence
Others
textmining
co-expression
protein homology
Your Input:
Neighborhood
Gene Fusion
Cooccurrence
Coexpression
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[Homology]
Score
speESpermidine synthase (putrescine aminopropyltransferase); Involved in the biosynthesis of polyamines which play a significant role in the structural and functional organization in the chromoid of E.coli by compacting DNA and neutralizing negative charges. Catalyzes the irreversible transfer (ping-pong mechanism) of a propylamine group from the amino donor S-adenosylmethioninamine (decarboxy-AdoMet) to putrescine (1,4-diaminobutane) to yield spermidine. Cadaverine (1,5-diaminopentane) and spermidine can also be used as the propylamine acceptor. (288 aa)    
Predicted Functional Partners:
speD
S-adenosylmethionine decarboxylase; Catalyzes the decarboxylation of S-adenosylmethionine to S- adenosylmethioninamine (dcAdoMet), the propylamine donor required for the synthesis of the polyamines spermine and spermidine from the diamine putrescine.
 
 
 0.999
speB
Agmatinase; Catalyzes the formation of putrescine from agmatine.
  
 
 0.991
speC
Ornithine decarboxylase, constitutive; Ornithine decarboxylase isozyme; Protein involved in polyamine biosynthetic process.
  
 
 0.989
speG
Spermidine N(1)-acetyltransferase; Involved in the protection against polyamine toxicity by regulating their concentration. Catalyzes the transfer of an acetyl group from acetyl coenzyme A (AcCoA) to the primary amino groups of spermidine to yield N(1)- and N(8)-acetylspermidine. It can also use polyamines such as spermine, but not putrescine.
    
 0.986
speF
Ornithine decarboxylase isozyme, inducible; Protein involved in polyamine biosynthetic process; Belongs to the Orn/Lys/Arg decarboxylase class-I family.
  
 
 0.982
puuA
Glutamate--putrescine ligase; Involved in the breakdown of putrescine via the biosynthesis of gamma-L-glutamylputrescine. It is able to use several diamines, spermidine and spermine. Absolutely essential to utilize putrescine as both nitrogen and carbon sources and to decrease the toxicity of putrescine, which can lead to inhibition of cell growth and protein synthesis; Belongs to the glutamine synthetase family.
     
 0.980
patA
Putrescine:2-oxoglutaric acid aminotransferase, PLP-dependent; Catalyzes the aminotransferase reaction from putrescine to 2- oxoglutarate, leading to glutamate and 4-aminobutanal, which spontaneously cyclizes to form 1-pyrroline. This is the first step in one of two pathways for putrescine degradation, where putrescine is converted into 4- aminobutanoate (gamma-aminobutyrate or GABA) via 4-aminobutanal, which allows E.coli to grow on putrescine as the sole nitrogen source. Also functions as a cadaverine transaminase in a a L-lysine degradation pathway to succinate that proceeds via cad [...]
     
 0.949
gss
Glutathionylspermidine amidase and glutathionylspermidine synthetase; 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. [...]
    
 0.938
mtn
5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase; Catalyzes the irreversible cleavage of the glycosidic bond in both 5'-methylthioadenosine (MTA) and S-adenosylhomocysteine (SAH/AdoHcy) to adenine and the corresponding thioribose, 5'- methylthioribose and S-ribosylhomocysteine, respectively. Also cleaves 5'-deoxyadenosine, a toxic by-product of radical S-adenosylmethionine (SAM) enzymes, into 5- deoxyribose and adenine. Thus, is required for in vivo function of the radical SAM enzymes biotin synthase and lipoic acid synthase, that are inhibited by 5'-deoxyadenosine accumulati [...]
  
 
 0.904
ldcC
Lysine decarboxylase 2, constitutive; Plays a role in lysine utilization by acting as a lysine decarboxylase.
 
 
 0.776
Your Current Organism:
Escherichia coli K12
NCBI taxonomy Id: 511145
Other names: E. coli str. K-12 substr. MG1655, Escherichia coli MG1655, Escherichia coli str. K-12 substr. MG1655, Escherichia coli str. K12 substr. MG1655, Escherichia coli str. MG1655, Escherichia coli strain MG1655
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