Issue 5, 2022

Corrole–protein interactions in H-NOX and HasA

Abstract

Replacing the native porphyrin cofactor in haem proteins has led to the development of novel designer proteins for a variety of applications. In most cases, haem analogues bind in a way that is comparable to the iron porphyrin, but this is not necessarily the case for complexes bearing non-exchangeable ligands. This study probes how a P[double bond, length as m-dash]O corrole binds to functionally disparate hemoproteins: a haem-dependent oxygen sensor (H-NOX) and a haem-scavenging protein (HasA). The results demonstrate that the protein–cofactor interactions are distinct from the native, haem-bound holoprotein. In H-NOX, the P[double bond, length as m-dash]O unit primarily hydrogen bonds with the haem-ligating histidine (H102), rather than the hydrogen-bonding network that stabilises the Fe(II)–O2 complex in the native protein. In the absence of H102, the protein is still able to bind the corrole, albeit at reduced levels. Molecular dynamics simulations were utilised to determine the flexibility of apo H-NOX and revealed the coupled motion of key residues necessary for corrole binding. In the case of HasA, the P[double bond, length as m-dash]O unit does not primarily interact with either the haem-ligating histidine (H32) or tyrosine (Y75). Instead, histidine 83, the hydrogen-bonding partner for Y75, is critical for P[double bond, length as m-dash]O corrole binding. The conformation of HasA is interrogated by site-specifically labelling the protein and exploiting Förster resonance energy transfer (FRET) to determine the dye–cofactor distance. HasA reconstituted with the P[double bond, length as m-dash]O corrole exhibits an extended, apo-like conformation. Together, these results demonstrate that non-natural cofactors can bind to proteins in unexpected ways and highlight the need to uncover these interactions for the further development of designer haem proteins.

Graphical abstract: Corrole–protein interactions in H-NOX and HasA

Supplementary files

Article information

Article type
Paper
Submitted
06 Jan 2022
Accepted
20 Mar 2022
First published
21 Mar 2022
This article is Open Access
Creative Commons BY-NC license

RSC Chem. Biol., 2022,3, 571-581

Corrole–protein interactions in H-NOX and HasA

C. M. Lemon, A. J. Nissley, N. R. Latorraca, E. C. Wittenborn and M. A. Marletta, RSC Chem. Biol., 2022, 3, 571 DOI: 10.1039/D2CB00004K

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements