Summary: Bacterial SH3 domain
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Bacterial SH3 domain Provide feedback
This family consists of several hypothetical bacterial proteins of unknown function. These are composed of SH3-like domains.
Internal database links
|Similarity to PfamA using HHSearch:||SH3_3|
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR010466SH3 (src Homology-3) domains are small protein modules containing approximately 50 amino acid residues [PUBMED:15335710, PUBMED:11256992]. They are found in a great variety of intracellular or membrane-associated proteins [PUBMED:1639195, PUBMED:14731533, PUBMED:7531822] for example, in a variety of proteins with enzymatic activity, in adaptor proteins that lack catalytic sequences and in cytoskeletal proteins, such as fodrin and yeast actin binding protein ABP-1.
The SH3 domain has a characteristic fold which consists of five or six beta-strands arranged as two tightly packed anti-parallel beta sheets. The linker regions may contain short helices [PUBMED:]. The surface of the SH3-domain bears a flat, hydrophobic ligand-binding pocket which consists of three shallow grooves defined by conservative aromatic residues in which the ligand adopts an extended left-handed helical arrangement. The ligand binds with low affinity but this may be enhanced by multiple interactions. The region bound by the SH3 domain is in all cases proline-rich and contains PXXP as a core-conserved binding motif. The function of the SH3 domain is not well understood but they may mediate many diverse processes such as increasing local concentration of proteins, altering their subcellular location and mediating the assembly of large multiprotein complexes [PUBMED:7953536].
This family consists of several hypothetical bacterial proteins of unknown function, but that contain an SH-3 region.
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Src homology-3 (SH3) domains are comprised of about 60 amino acids, performing either an assembly or regulatory role. For example, SH3 domains in the Grb2 adaptor protein are essential for protein-protein interactions and signal transduction in the p21 Ras-dependent growth factor signaling pathway. Alternatively, SH3 performs a regulatory role in the Src family of tyrosine kinases. SH3 domains bind a variety of peptide ligands, many of which contain a PxxP motif. This PxxP motif is flanked by different specificity elements . Structures of SH3 domains, both free and ligand complexed, have provided insights into the mechanism of ligand recognition. The SH3 fold consists of two anti-parallel beta sheets that lie at right angles to each other. Within the fold, there are two variable loops, referred to as RT and n-Src loops. When SH3 binds to its ligand, the proline rich ligand adopts a PPII helix conformation, with the PPII helix structure recognised by a pair of grooves on the surface of the SH3 domain that bind turns of the helix. The SH3 grooves are formed by a series of nearly parallel, well-conserved aromatic residues .
The clan contains the following 9 members:hSH3 SH3_1 SH3_2 SH3_3 SH3_4 SH3_5 SH3_6 SH3_8 SH3_9
We make a range of alignments for each Pfam-A family:
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Curation and family details
|Seed source:||Pfam-B_13248 (release 9.0)|
|Author:||Moxon SJ, Bateman A|
|Number in seed:||29|
|Number in full:||1011|
|Average length of the domain:||55.40 aa|
|Average identity of full alignment:||27 %|
|Average coverage of the sequence by the domain:||37.89 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||8|
|Download:||download the raw HMM for this family|
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