ADP‐ribosyltransferase from beef liver which ADP‐ribosylates elongation factor‐2

FEBS Letters

Lee, Herbert¹  Muller, Patrick¹  Iglewski, Wallace J.¹ 

[1] Department of Microbiology and Immunology, Oregon Health Sciences University, Portland, OR 97221, USA

关键词: ADP-ribosyltransferase;    Elongation factor-2;    Bacteria toxin;    Posttranslational modification;    Protein synthesis;    Liver;   

DOI  :  10.1016/0014-5793(84)81028-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Fragment A of diphtheria toxin and Pseudomonas toxin A intoxicate cells by ADP-ribosylating the diphthamide residue of elongation factor-2 (EF-2) resulting in an inhibition of protein synthesis [1–3]. A cellular enzyme from polyoma virus transformed baby hamster kidney (pyBHK) cells ADP-ribosylates EF-2 in an identical manner [4]. Here we describe a similar cellular enzyme from beef liver which transfers [adenosine-¹⁴C]ADP-ribose from NAD to EF-2. The ¹⁴C-label can be removed from the EF-2 by snake venom phosphodiesterase as a soluble product which comigrates with AMP on TLC plates, indicating the ¹⁴C-label is present on EF-2 as monomeric units of ADP-ribose. Furthermore, the forward transferase reaction catalyzed by the beef liver ADP-ribosyltransferase is reversible by excess diphtheria toxin fragment A, with the formation of ¹⁴C-labeled NAD, indicating that both transferases ADP-ribosylate the same site on the diphthamide residue of EF-2. Thus, beef liver and pyBHK mono(ADP-ribosyl) transferases both modify the diphthamide residue of EF-2, in a manner identical to diphtheria toxin fragment A and Pseudomonas toxin A. These results suggest the cellular enzyme is probably ubiquitous among eukaryotic cells.

【 授权许可】

Unknown