Change search
ReferencesLink to record
Permanent link

Direct link
Escherichia coli Peptide Binding Protein OppA Has a Preference for Positively Charged Peptides
Stockholm University, Faculty of Science, Department of Biochemistry and Biophysics. (Jan-Willem de Gier)
Show others and affiliations
2011 (English)In: Journal of Molecular Biology, ISSN 0022-2836, E-ISSN 1089-8638, Vol. 414, no 1, 75-85 p.Article in journal (Refereed) Published
Abstract [en]

The Escherichia coli peptide binding protein OppA is an essential component of the oligopeptide transporter Opp. Based on studies on its orthologue from Salmonella typhimurium, it has been proposed that OppA binds peptides between two and five amino acids long, with no apparent sequence selectivity. Here, we studied peptide binding to E. coli OppA directly and show that the protein has an unexpected preference for basic peptides. OppA was expressed in the periplasm, where it bound to available peptides. The protein was purified in complex with tightly bound peptides. The crystal structure (up to 2.0 angstrom) of OppA liganded with the peptides indicated that the protein has a preference for peptides containing a lysine. Mass spectrometry analysis of the bound peptides showed that peptides between two and five amino acids long bind to the protein and indeed hinted at a preference for positively charged peptides. The preference of OppA for peptides with basic residues, in particular lysines, was corroborated by binding studies with peptides of defined sequence using isothermal titration calorimetry and intrinsic protein fluorescence titration. The protein bound tripeptides and tetrapeptides containing positively charged residues with high affinity, whereas related peptides without lysines/arginines were bound with low affinity. A structure of OppA in an open conformation in the absence of ligands was also determined to 2.0 angstrom, revealing that the initial binding site displays a negative surface charge, consistent with the observed preference for positively charged peptides. Taken together, E. coli OppA appears to have a preference for basic peptides.

Place, publisher, year, edition, pages
2011. Vol. 414, no 1, 75-85 p.
Keyword [en]
peptide binding protein, oligopeptide transporter, ABC transporter, Escherichia coli, substrate binding protein
National Category
Biochemistry and Molecular Biology
URN: urn:nbn:se:su:diva-70672DOI: 10.1016/j.jmb.2011.09.043ISI: 000297778800006OAI: diva2:482475
authorCount :9Available from: 2012-01-24 Created: 2012-01-23 Last updated: 2012-01-24Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Klepsch, Mirjamde Gier, Jan-Willem
By organisation
Department of Biochemistry and Biophysics
In the same journal
Journal of Molecular Biology
Biochemistry and Molecular Biology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 14 hits
ReferencesLink to record
Permanent link

Direct link