1bkb

<table><tr><td colspan='2'>[[1bkb]] is a 1 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1BKB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1BKB FirstGlance]. <br>

</td></tr><tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene></td></tr>

[[https://www.uniprot.org/uniprot/IF5A_PYRAE IF5A_PYRAE]] Functions by promoting the formation of the first peptide bond.

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== Publication Abstract from PubMed ==

BACKGROUND: Translation initiation factor 5A (IF-5A) is reported to be involved in the first step of peptide bond formation in translation, to be involved in cell-cycle regulation and to be a cofactor for the Rev and Rex transactivator proteins of human immunodeficiency virus-1 and T-cell leukemia virus I, respectively. IF-5A contains an unusual amino acid, hypusine (N-epsilon-(4-aminobutyl-2-hydroxy)lysine), that is required for its function. The first step in the post-translational modification of lysine to hypusine is catalyzed by the enzyme deoxyhypusine synthase, the structure of which has been published recently. RESULTS: IF-5A from the archebacterium Pyrobaculum aerophilum has been heterologously expressed in Escherichia coli with selenomethionine substitution. The crystal structure of IF-5A has been determined by multiwavelength anomalous diffraction and refined to 1.75 A. Unmodified P. aerophilum IF-5A is found to be a beta structure with two domains and three separate hydrophobic cores. CONCLUSIONS: The lysine (Lys42) that is post-translationally modified by deoxyhypusine synthase is found at one end of the IF-5A molecule in an turn between beta strands beta4 and beta5; this lysine residue is freely solvent accessible. The C-terminal domain is found to be homologous to the cold-shock protein CspA of E. coli, which has a well characterized RNA-binding fold, suggesting that IF-5A is involved in RNA binding.

Structure of translation initiation factor 5A from Pyrobaculum aerophilum at 1.75 A resolution.,Peat TS, Newman J, Waldo GS, Berendzen J, Terwilliger TC Structure. 1998 Sep 15;6(9):1207-14. PMID:9753699<ref>PMID:9753699</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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== References ==

<references/>

[[Category: Berendzen, J]]

[[Category: Newman, J]]

[[Category: Peat, T S]]

[[Category: Terwilliger, T C]]

[[Category: Waldo, G S]]

[[Category: Translation]]

[[Category: Translation initiation factor]]