Deciphering the Dialogue between the GTPase Cycle, Metal Binding, and Quaternary Structure of Escherichia coli HypB
Year: 2019
Type: dissertation
Abstract: During the maturation of the bimetallic catalytic centre of [NiFe]-hydrogenase enzymes, the nickel insertion step is facilitated by the metallochaperones HypB and HypA. However, many of the underlying mechanisms behind the process of selective metal transfer from HypB to HypA are still unclear. To better understand these mechanisms, single-residue mutations were engineered into the metal-binding site of HypB. Experiments with C198T HypB revealed that C198 likely does not serve as a link between metal binding and GTP hydrolysis activity. However, complex formation between C198T HypB and HypA is impacted. Complex formation – and the transfer of Ni(II) – between F202A HypB and HypA has also been disrupted. These results demonstrate the importance of the HypB-HypA complex interface during selective nickel transfer from HypB to HypA, and suggest that there is allosteric regulation of complex formation, driven by communication from the metal coordination environment of HypB to the HypB-HypA complex interface.
Source: TSpace (University of Toronto)
Author: Juliana Seok
Language: English
Subfield: Biochemistry
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W3156340841