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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 PDOC00274
Eukaryotic initiation factor 5A hypusine signature


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PURL: https://purl.expasy.org/prosite/documentation/PDOC00274

Description

Eukaryotic initiation factor 5A (eIF-5A) (formerly known as eIF-4D) [1,2] is a small protein whose precise role in the initiation of protein synthesis is not known. It appears to promote the formation of the first peptide bond. eIF-5A seems to be the only eukaryotic protein to contain an hypusine residue. Hypusine is derived from lysine by the post-translational addition of a butylamino group (from spermidine) to the epsilon-amino group of lysine. The hypusine group is essential to the function of eIF-5A.

A hypusine-containing protein has been found in archaebacteria such as Sulfolobus acidocaldarius or Methanococcus jannaschii; this protein is highly similar to eIF-5A and could play a similar role in protein biosynthesis.

The signature we developed for eIF-5A is centered around the hypusine residue.

Last update:

November 1997 / Pattern and text revised.

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Technical section

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

IF5A_HYPUSINE, PS00302; Eukaryotic initiation factor 5A hypusine signature  (PATTERN)


References

1AuthorsPark M.H. Wolff E.C. Folk J.E.
TitleHypusine: its post-translational formation in eukaryotic initiation factor 5A and its potential role in cellular regulation.
SourceBiofactors 4:95-104(1993).
PubMed ID8347280

2AuthorsSchnier J. Schwelberger H.G. Smit-McBride Z. Kang H.A. Hershey J.W.
TitleTranslation initiation factor 5A and its hypusine modification are essential for cell viability in the yeast Saccharomyces cerevisiae.
SourceMol. Cell. Biol. 11:3105-3114(1991).
PubMed ID1903841



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