Abstract
The paramagnetic effect of Mn(II) on 13C and 31P nuclear magnetic resonance signals from the [2-13C]ATP adenylylated glutamine synthetase [L-glutamate:ammonia ligase (ADP-forming); EC 6.3.1.2] from Escherichia coli was measured. This effect permitted the determination of distances from the 2-C position and the phosphorus of covalently bound AMP to the two Mn(II) binding sites, n1 and n2. Binding of Mn(II) to the n1 site converts an inactive apo-enzyme to its active form, while the metal ion bound at n2 occupies the metal-nucleotide substrate site. The distances from Mn(II) at the n1 and n2 sites to phosphorus are ∼10 and ∼7 Å and to the 2-C position of the adenine ring are ∼12 and ∼11 Å, respectively. The fluorescence energy transfer method was used to determine distances between Co(II) at n1 and n2 and the adenylyl site. For this experiment the enzyme was adenylylated with ε-ATP. The distances between ε-adenine and Co(II) at n1 and n2 are ∼13 and ∼11 Å, respectively. Quantitation of the paramagnetic effect due to Co(II) on the 31P nuclear magnetic resonance signal yielded values of 8 and 6 Å for the distances between the phosphorus of the covalently bound AMP and the n1 and n2 sites, respectively. The results reveal that the covalent modification site is very close to the catalytic center of the enzyme. In this study both nuclear magnetic resonance and fluorescence energy transfer techniques have been used to determine distances between the same set of sites on an enzyme surface.
Keywords: covalent modification, distance determination, ε-ATP, [13C]ATP, adenylylation
Full text
PDF




Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Adler S. P., Purich D., Stadtman E. R. Cascade control of Escherichia coli glutamine synthetase. Properties of the PII regulatory protein and the uridylyltransferase-uridylyl-removing enzyme. J Biol Chem. 1975 Aug 25;250(16):6264–6272. [PubMed] [Google Scholar]
- Chock P. B., Huang C. Y., Timmons R. B., Stadtman E. R. Epsilon-adenylylated glutamine synthetase: an internal fluorescence probe for enzyme conformation. Proc Natl Acad Sci U S A. 1973 Nov;70(11):3134–3138. doi: 10.1073/pnas.70.11.3134. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Denton M. D., Ginsburg A. Conformational changes in glutamine synthetase from Escherichia coli. I. The binding of Mn2+ in relation to some aspects of the enzyme structure and activity. Biochemistry. 1969 Apr;8(4):1714–1725. doi: 10.1021/bi00832a055. [DOI] [PubMed] [Google Scholar]
- Fung C. H., Mildvan A. S., Leigh J. S., Jr Electron and nuclear magnetic resonance studies of the interaction of pyruvate with transcarboxylase. Biochemistry. 1974 Mar 12;13(6):1160–1169. doi: 10.1021/bi00703a017. [DOI] [PubMed] [Google Scholar]
- Hunt J. B., Ginsburg A. Some kinetics of the interaction of divalent cations with glutamine synthetase from Escherichia coli. Metal ion induced conformational changes. Biochemistry. 1972 Sep 26;11(20):3723–3735. doi: 10.1021/bi00770a010. [DOI] [PubMed] [Google Scholar]
- Hunt J. B., Smyrniotis P. Z., Ginsburg A., Stadtman E. R. Metal ion requirement by glutamine synthetase of Escherichia coli in catalysis of gamma-glutamyl transfer. Arch Biochem Biophys. 1975 Jan;166(1):102–124. doi: 10.1016/0003-9861(75)90370-7. [DOI] [PubMed] [Google Scholar]
- Latt S. A., Auld D. S., Vallee B. L. Distance measurements at the active site of carboxypeptidase A during catalysis. Biochemistry. 1972 Aug 1;11(16):3015–3022. doi: 10.1021/bi00766a013. [DOI] [PubMed] [Google Scholar]
- Miller R. E., Shelton E., Stadtman E. R. Zinc-induced paracrystalline aggregation of glutamine synthetase. Arch Biochem Biophys. 1974 Jul;163(1):155–171. doi: 10.1016/0003-9861(74)90465-2. [DOI] [PubMed] [Google Scholar]
- Rhee S. G., Chock P. B. Mechanistic studies of glutamine synthetase from Escherichia coli: kinetics of ADP and orthophosphate binding to the unadenylylated enzyme. Biochemistry. 1976 Apr 20;15(8):1755–1760. doi: 10.1021/bi00653a025. [DOI] [PubMed] [Google Scholar]
- Rhee S. G., Villafranca J. J., Chock P. B., Stadtman E. R. Direct evidence for separate binding sites for L-Glu and amino acid feedback inhibitors on unadenylylated glutamine synthetase from E. coli. Biochem Biophys Res Commun. 1977 Sep 9;78(1):244–250. doi: 10.1016/0006-291x(77)91246-3. [DOI] [PubMed] [Google Scholar]
- Secrist J. A., 3rd, Barrio J. R., Leonard N. J., Weber G. Fluorescent modification of adenosine-containing coenzymes. Biological activities and spectroscopic properties. Biochemistry. 1972 Sep 12;11(19):3499–3506. doi: 10.1021/bi00769a001. [DOI] [PubMed] [Google Scholar]
- Segal A., Stadtman E. R. Effects of cobaltous ion on various catalytic parameters and on heterologous subunit interactions of Escherichia coli glutamine synthetase. Arch Biochem Biophys. 1972 Sep;152(1):356–366. doi: 10.1016/0003-9861(72)90225-1. [DOI] [PubMed] [Google Scholar]
- Segal A., Stadtman E. R. Variation of the conformational states of Escherichia coli glutamine synthetase by interaction with different divalent cations. Arch Biochem Biophys. 1972 Sep;152(1):367–377. doi: 10.1016/0003-9861(72)90226-3. [DOI] [PubMed] [Google Scholar]
- Shapiro B. M., Stadtman E. R. 5'-adenylyl-O-tyrosine. The novel phosphodiester residue of adenylylated glutamine synthetase from Escherichia coli. J Biol Chem. 1968 Jul 10;243(13):3769–3771. [PubMed] [Google Scholar]
- Villafranca J. J., Ash D. E., Wedler F. C. Manganese (II) and substrate interaction with unadenylylated glutamine synthetase (Escherichia coli w). II. Electron paramagnetic resonance and nuclear magnetic resonance studies of enzyme-bound manganese(II) with substrates and a potential transition-state analogue, methionine sulfoximine. Biochemistry. 1976 Feb 10;15(3):544–553. doi: 10.1021/bi00648a014. [DOI] [PubMed] [Google Scholar]
- Villafranca J. J., Balakrishnan M. S., Wedler F. C. Determination of metal-metal distances in E. coli glutamine synthetase by EPR. Biochem Biophys Res Commun. 1977 Mar 21;75(2):464–471. doi: 10.1016/0006-291x(77)91065-8. [DOI] [PubMed] [Google Scholar]
- Villafranca J. J., Wedler F. C. Nuclear magnetic resonance study of the complexes of manganese(II) and fully adenylated glutamine synthetase (Escherichia coli W). Frequency, temperature, and substrate dependence of water proton relaxation rates. Biochemistry. 1974 Jul 30;13(16):3286–3291. doi: 10.1021/bi00713a017. [DOI] [PubMed] [Google Scholar]
