Time-resolved crystallographic and spectroscopic studies of the mononuclear non-haem iron oxygenases, IPNS and VioC
Lead Research Organisation:
University of Oxford
Department Name: Interdisciplinary Bioscience DTP
Abstract
Research within the field of structural biology aims to provide full understanding of the structure and
function of biological macromolecules, information that ultimately facilitates rational drug design and
protein engineering. Application of structural biology to the class of mononuclear non-haem iron
oxygenases has potential to help combat the growing problem of antibiotic resistance. These enzymes
are responsible for the incorporation of molecular oxygen (O2) into a wide variety of substrates. Due
to the intrinsic properties of dioxygen, reactions are difficult but biologically rewarding, exemplified
by the number of enzymes within the family and the range of functions they facilitate. Two structurally
similar enzymes from this class are isopenicillin N synthase (IPNS) and viomycin biosynthetic protein
C. The former catalyses the of bicyclic ring closure forming the B-lactam core of penicillin and
cephalosporin antibiotics. Viomycin biosynthetic protein C (VioC) catalyses hydroxylation of L-arginine
(L-arg), which is subsequently cyclised forming the non-standard amino acid L-capreomycidine (L-cam)
and incorporated into the peptide precursor of viomycin. While structurally similar, IPNS and VioC are
mechanistically distinct. VioC catalysis requires the presence of a cofactor (a-ketoglutarate) while the
IPNS reaction is cofactor-independent. Due to the importance of this class of enzymes, both proteins
have been subject to extensive research. Nevertheless, questions of their precise reaction
mechanisms remain unanswered. The aim of this project is to fully elucidate the mechanisms of both
enzymes. The project will involve the use of time-resolved crystallographic studies made possible by
X-ray free electron laser facilities. Due to structural similarity within the oxygenase family, the
information collected from these enzymes will provide understanding of a wide range of biological
relevant oxygenase proteins.
function of biological macromolecules, information that ultimately facilitates rational drug design and
protein engineering. Application of structural biology to the class of mononuclear non-haem iron
oxygenases has potential to help combat the growing problem of antibiotic resistance. These enzymes
are responsible for the incorporation of molecular oxygen (O2) into a wide variety of substrates. Due
to the intrinsic properties of dioxygen, reactions are difficult but biologically rewarding, exemplified
by the number of enzymes within the family and the range of functions they facilitate. Two structurally
similar enzymes from this class are isopenicillin N synthase (IPNS) and viomycin biosynthetic protein
C. The former catalyses the of bicyclic ring closure forming the B-lactam core of penicillin and
cephalosporin antibiotics. Viomycin biosynthetic protein C (VioC) catalyses hydroxylation of L-arginine
(L-arg), which is subsequently cyclised forming the non-standard amino acid L-capreomycidine (L-cam)
and incorporated into the peptide precursor of viomycin. While structurally similar, IPNS and VioC are
mechanistically distinct. VioC catalysis requires the presence of a cofactor (a-ketoglutarate) while the
IPNS reaction is cofactor-independent. Due to the importance of this class of enzymes, both proteins
have been subject to extensive research. Nevertheless, questions of their precise reaction
mechanisms remain unanswered. The aim of this project is to fully elucidate the mechanisms of both
enzymes. The project will involve the use of time-resolved crystallographic studies made possible by
X-ray free electron laser facilities. Due to structural similarity within the oxygenase family, the
information collected from these enzymes will provide understanding of a wide range of biological
relevant oxygenase proteins.
Organisations
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| BB/M011224/1 | 01/10/2015 | 31/03/2024 | |||
| 2107984 | Studentship | BB/M011224/1 | 01/10/2018 | 30/09/2022 |