Unique Binding of a Non-Natural L,L,L-Substrate by Isopenicillin N Synthase
Howard-Jones, A.R., Rutledge, P.J., Clifton, I.J., Adlington, R.M., Baldwin, J.E.(2005) Biochem Biophys Res Commun 336: 702
- PubMed: 16143309 
- DOI: https://doi.org/10.1016/j.bbrc.2005.08.155
- Primary Citation of Related Structures:  
2BU9 - PubMed Abstract: 
Isopenicillin N synthase (IPNS) is a non-haem iron oxidase that catalyses the formation of isopenicillin N from the tripeptide delta-(L-alpha-aminoadipoyl)-L-cysteinyl-D-valine. In this report, we describe the crystal structure of the enzyme with a non-natural L,L,L-tripeptide substrate, delta-(L-alpha-aminoadipoyl)-L-cysteinyl-L-3,3,3,3',3',3'-hexafluorovaline. This structure reveals a strong binding interaction of the tripeptide within the active site and a unique conformation for the non-natural L,L,L-diastereomer. Taken together, these findings provide a possible rationale for the previously observed inhibitory effects of L,L,L-tripeptide substrates on IPNS activity.
Organizational Affiliation: 
Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK. annaleise_howard-jones@hms.harvard.edu