Abstract
We describe a non-invasive technique for determining pH in biomolecular NMR sample using buffer components (formate, tris, piperazine, and imidazole) as internal pH indicators, whose 1H NMR chemical shifts are sensitive to pH in a range from 2.5 to 9.8. This method is suitable for a wide range of applications where samples are handled intensively during NMR titrations or in high throughput analysis in structural genomics or metabolomics.
This is a preview of subscription content, log in via an institution to check access.
Abbreviations
- NMR:
-
Nuclear magnetic resonance
- HSQC:
-
Heteronuclear single quantum coherence
References
DeFronzo M, Gillies RJ (1987) Characterization of methylphosphonate as a 31P NMR pH indicator. J Biol Chem 262:11032–11037
Li MX, Spyracopoulos L, Sykes BD (1999) Binding of cardiac troponin-I147–163 induces a structural opening in human cardiac troponin-C. Biochemistry 38:8289–8298
Lindhout DA, Sykes BD (2003) Structure and dynamics of the C-domain of human cardiac troponin C in complex with the inhibitory region of human cardiac troponin I. J Biol Chem 278:27024–27034
Pietri S, Miollan M, Martel S, Le Moigne F, Blaive B, Culcasi M (2000) Alpha- and beta -phosphorylated amines and pyrrolidines, a new class of low toxic highly sensitive 31P NMR pH indicators. Modeling of pKa and chemical shift values as a function of substituents. J Biol Chem 275:19505–19512
Pietri S, Martel S, Culcasi M, Delmas-Beauvieux MC, Canioni P, Gallis JL (2001) Use of diethyl(2-methylpyrrolidin-2-yl)phosphonate as a highly sensitive extra- and intracellular 31P NMR pH indicator in isolated organs. Direct NMR evidence of acidic compartments in the ischemic and reperfused rat liver. J Biol Chem 276:1750–1758
Rabenstein DL, Fan SY (1986) Proton nuclear magnetic resonance spectroscopy of aqueous solutions: complete elimination of the water resonance by spin-spin relaxation. Anal Chem 58:3178–3184
Sia SK, Li MX, Spyracopoulos L, Gagne SM, Liu W, Putkey JA, Sykes BD (1997) Structure of cardiac muscle troponin C unexpectedly reveals a closed regulatory domain. J Biol Chem 272:18216–18221
Sorkin DL, Miller AF (1997) Spectroscopic measurement of a long-predicted active site pK in iron-superoxide dismutase from Escherichia coli. Biochemistry 36:4916–4924
Szakacs Z, Hagele G, Tyka R (2004) 1H/31P NMR pH indicator series to eliminate the glass electrode in NMR spectroscopic pKa determinations. Anal Chim Acta 522:247–258
Taylor J, Deutsch C (1988) 19F-nuclear magnetic resonance: measurements of [O2] and pH in biological systems. Biophys J 53:227–233
Valcour AA, Woodworth RC (1986) Internal proton magnetic-resonance probes for pH titration of proteins. J Magn Reson 66:536–541
Vistad OB, Akporiaye DE, Taulelle F, Lillerud KP (2003) Morpholine, an in situ C-13 NMR pH meter for hydrothermal crystallogenesis of SAPO-34. Chem Mater 15:1650–1654
Acknowledgement
Authors would like to acknowledge Jeff DeVries for maintaining the spectrometers.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Baryshnikova, O.K., Williams, T.C. & Sykes, B.D. Internal pH indicators for biomolecular NMR. J Biomol NMR 41, 5–7 (2008). https://doi.org/10.1007/s10858-008-9234-6
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10858-008-9234-6