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We are deeply saddened by the passing of Amos Bairoch (1957–2025), the creator of PROSITE. We wish to dedicate our latest paper, published shortly before his death, to him. He will always be a source of inspiration to us.
Our deepest condolences go out to his family and friends, and to all those who had the privilege of working with him. Rest in peace, Amos. Your work will live on long after you are gone.
Amos Bairoch

PROSITE documentation PDOC51784
Exonuclease I (ExoI) SH3-like and C-terminal domains profiles


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PURL: https://purl.expasy.org/prosite/documentation/PDOC51784

Description

In bacteria, exonuclease I (ExoI) is a monomeric processive 3'-5' exonuclease that degrades single-stranded DNA. The enzyme has been implicated as primarily being involved in repairing frameshift mutations. ExoI consists of three domains: an N-terminal nuclease domain with homology to the proofreading domain of E. coli DNA polymereae I and other DnaQ superfamily enzymes, a central domain with a portion that resembles an SH3 domain fold and a C-terminal α-helical domain. While a typical SH3-like domain consists of five or six antiparallel β-strands that form a compact β-sandwich, the β-sandwich of the SH3-like domain in ExoI is surrounded by α-helices, resulting in a substantially elaborated fold (see <PDB:1FXX>) [1,2,3].

The profile we developed covers the entire ExoI SH3-like and C-terminal domains.

Last update:

December 2015 / First entry.

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Technical section

PROSITE methods (with tools and information) covered by this documentation:

EXOI_C, PS51785; Exonuclease I (ExoI) C-terminal domain profile  (MATRIX)

EXOI_SH3, PS51784; Exonuclease I (ExoI) SH3-like domain profile  (MATRIX)


References

1AuthorsBreyer W.A. Matthews B.W.
TitleStructure of Escherichia coli exonuclease I suggests how processivity is achieved.
SourceNat. Struct. Biol. 7:1125-1128(2000).
PubMed ID11101894
DOI10.1038/81978

2AuthorsBusam R.D.
TitleStructure of Escherichia coli exonuclease I in complex with thymidine 5'-monophosphate.
SourceActa Crystallogr. D 64:206-210(2008).
PubMed ID18219121
DOI10.1107/S090744490706012X

3AuthorsKorada S.K.C. Johns T.D. Smith C.E. Jones N.D. McCabe K.A. Bell C.E.
TitleCrystal structures of Escherichia coli exonuclease I in complex with single-stranded DNA provide insights into the mechanism of processive digestion.
SourceNucleic Acids Res. 41:5887-5897(2013).
PubMed ID23609540
DOI10.1093/nar/gkt278



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