Rapid fold and structure determination of the archaeal translation elongation factor 1beta from Methanobacterium thermoautotrophicum.
The tertiary fold of the elongation factor, aEF-1beta, from Methanobacterium thermoautotrophicum was determined in a high-throughput fashion using a minimal set of NMR experiments. NMR secondary structure prediction, deuterium exchange experiments and the analysis of chemical shift perturbations were combined to identify the protein fold as an alpha-beta sandwich typical of many RNA binding proteins including EF-G. Following resolution of the tertiary fold, a high resolution structure of aEF-1beta was determined using heteronuclear and homonuclear NMR experiments and a semi-automated NOESY assignment strategy. Analysis of the aEF-1beta structure revealed close similarity to its human analogue, eEF-1beta. In agreement with studies on EF-Ts and human EF-1beta, a functional mechanism for nucleotide exchange is proposed wherein Phe46 on an exposed loop acts as a lever to eject GDP from the associated elongation factor G-protein, aEF-1alpha. aEF-1beta was also found to bind calcium in the groove between helix alpha2 and strand beta4. This novel feature was not observed previously and may serve a structural function related to protein stability or may play a functional role in archaeal protein translation.
Kozlov
G
G
McGill University, Department of Biochemistry, Montreal, PQ, Canada.
Ekiel
I
I
Beglova
N
N
Yee
A
A
Dharamsi
A
A
Engel
A
A
Siddiqui
N
N
Nong
A
A
Gehring
K
K
D019843:Archaeal Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000737:chemistry; D006801:Humans; D017014:Methanobacterium / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D020648:Peptide Elongation Factor 1 / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D017510:Protein Folding; D017433:Protein Structure, Secondary; D011993:Recombinant Fusion Proteins / Q000737:chemistry
D019843:Archaeal Proteins; D002135:Calcium-Binding Proteins; D020648:Peptide Elongation Factor 1; D011993:Recombinant Fusion Proteins