2MZB

Solution structural studies of GTP:adenosylcobinamide-phosphate guanylyltransferase (CobY) from Methanocaldococcus jannaschii

Summary for 2MZB

• Entry DOI: 10.2210/pdb2mzb/pdb
• NMR Information: BMRB: 25482
• Descriptor: Adenosylcobinamide-phosphate guanylyltransferase (1 entity in total)
• Functional Keywords: transferase
• Biological source: Methanocaldococcus jannaschii
• Total number of polymer chains: 1
• Total formula weight: 21770.49

Authors

Singarapu, K.,Otte, M.,Tonelli, M.,Westler, W.M.,Escalante-Semerena, J.C.,Markley, J.L. (deposition date: 2015-02-11, release date: 2015-11-11, Last modification date: 2024-05-15)

Primary citation

Singarapu, K.K.,Otte, M.M.,Tonelli, M.,Westler, W.M.,Escalante-Semerena, J.C.,Markley, J.L.
Solution Structural Studies of GTP:Adenosylcobinamide-Phosphateguanylyl Transferase (CobY) from Methanocaldococcus jannaschii.
Plos One, 10:e0141297-e0141297, 2015

PubMed Abstract: GTP:adenosylcobinamide-phosphate (AdoCbi-P) guanylyl transferase (CobY) is an enzyme that transfers the GMP moiety of GTP to AdoCbi yielding AdoCbi-GDP in the late steps of the assembly of Ado-cobamides in archaea. The failure of repeated attempts to crystallize ligand-free (apo) CobY prompted us to explore its 3D structure by solution NMR spectroscopy. As reported here, the solution structure has a mixed α/β fold consisting of seven β-strands and five α-helices, which is very similar to a Rossmann fold. Titration of apo-CobY with GTP resulted in large changes in amide proton chemical shifts that indicated major structural perturbations upon complex formation. However, the CobY:GTP complex as followed by 1H-15N HSQC spectra was found to be unstable over time: GTP hydrolyzed and the protein converted slowly to a species with an NMR spectrum similar to that of apo-CobY. The variant CobYG153D, whose GTP complex was studied by X-ray crystallography, yielded NMR spectra similar to those of wild-type CobY in both its apo- state and in complex with GTP. The CobYG153D:GTP complex was also found to be unstable over time.

PubMed: 26513744
DOI: 10.1371/journal.pone.0141297

Experimental method

SOLUTION NMR