spacer
Quick search:
News
IntEnz release 37
  • A batch of new enzymes has been proposed for public review.
Plugins
Firefox
Install the IntEnz search plugin for Firefox 1.5 (not needed with Firefox 2 or IE 7).
Partners
ExPASy
Swiss Institute of Bioinformatics
The ENZYME data are an integral part of IntEnz, and the ENZYME flat file generated from IntEnz is available from our ftp site.
spacer
EBI Databases Enzymes IntEnz

IntEnz - Home

IntEnz (Integrated relational Enzyme database) is a freely available resource focused on enzyme nomenclature. IntEnz is created in collaboration with the Swiss Institute of Bioinformatics (SIB). This collaboration is responsible for the production of the ENZYME resource.
IntEnz contains the recommendations of the Nomenclature Committee of the International Union of Biochemistry and Molecular Biology (NC-IUBMB) on the nomenclature and classification of enzyme-catalysed reactions.

All data in IntEnz is freely accessible and available for anyone to use.

Search


You can use % as a wildcard, as well as some special characters Special characters
Examples: 1.1.1.1, alcohol%, α-glucosidase
Or try the advanced search.

Enzyme spotlight

EC 2.3.2.6
Leucyltransferase

Complex structure of LF-transferase and peptide Phe-Arg-Tyr-Leu-Gly Abstract:
Eubacterial leucyl/phenylalanyl-tRNA—protein transferase (LF-transferase) catalyses four types of ribosome-independent peptide-bond formation reactions: These modifications are essential for regulated degradation of intracellular proteins. The proteins thus modified are recognised by the ClpAP-specific adaptor protein ClpS and subsequently are degraded by the proteasome-like protease ClpAP [1]. The crystal structures of Escherichia coli LF-transferase complexes with phenyalanyl-adenosine (rA-Phe), with or without a short peptide bearing an N-terminal Arg residue, have been solved [2]. The superposition of the two structures allowed the catalytic mechanism of peptide-bond formation by LF-transferase to be deduced. The mechanism is similar to the reverse of the acylation step of proteolysis by serine proteases such as chymotrypsin [3]. In LF-transferase the electron relay from Asp-186 to Gln-188 of E. coli LF-transferase allows Gln-188 to attract a proton from the α-amino group of the N-terminal Arg of the acceptor peptide. This generates the attacking nucleophile for the carbonyl carbon of the aminoacyl bond of the aminoacyl-tRNA, thus facilitating peptide-bond formation.
References:
  1. Erbse, A., Schmidt, R., Bornemann, T., Schneider-Mergener, J., Mogk, A., Zahn, R., Dougan, D.A. and Bukau, B. (2006)
    ClpS is an essential component of the N-end rule pathway in Escherichia coli.
    Nature 439, 753-756. [PMID:16467841]
  2. Watanabe, K., Toh, Y., Suto, K., Shimizu, Y., Oka, N., Wada, T. and Tomita K. (2007)
    Protein-based peptide-bond formation by aminoacyl-tRNA protein transferase.
    Nature 449, 867-871. [PMID:17891155]
  3. Steitz, T.A. and Shulman, R.G. (1982)
    Crystallographic and NMR studies of the serine proteases.
    Annu. Rev. Biophys. Bioeng. 11, 419-444. [PMID:7049067]
Go to the gallery of previous releases spotlights.

Acknowledgements

EU The project is supported by the European Commission under FELICS, contract number 021902 (RII3) within the Research Infrastructure Action of the FP6 "Structuring the European Research Area" Programme.

spacer
spacer