Buffer optimization: Difference between revisions
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At Rutger’s University, NMR samples with promising spectra in the initial pH 6.5, 200 mM NaCl buffer are screened by <sup>1</sup>H-<sup>15</sup>N HSQC spectra after exchanging into | At Rutger’s University, NMR samples with promising spectra in the initial pH 6.5, 200 mM NaCl buffer are screened by <sup>1</sup>H-<sup>15</sup>N HSQC spectra after exchanging into 13 commonly used screening buffers (listed below). Exchange is performed using by a desalting column and NMR screening is done with a Bruker MicroCryoprobe.<ref>Rossi, P. et. al. (2010). "A microscale protein NMR sample screening pipeline." ''J. Biomol. NMR'', 46, 11-22.</ref><br> | ||
==== '''NMR screening and optimization buffers:''' ==== | |||
pH | MJ001 20mM MES, pH 6.5, 100mM NaCl, 5mM CaCl<sub>2</sub>, 10mM DTT, 50 uM DSS, 0.02% NaN<sub>3</sub>, 1x Proteinase Inhibitors, 5% D<sub>2</sub>O | ||
MJ002 20mM NH<sub>4</sub>OAc, pH 5.5, 100mM NaCl, 5mM CaCl<sub>2</sub>, 10mM DTT, 50 uM DSS, 0.02% NaN<sub>3</sub>, 1X Proteinase Inhibitors, 5% D<sub>2</sub>O<br> | |||
pH 5 | MJ003 20mM NH<sub>4</sub>OAc, pH 4.5, 100mM NaCl, 5mM CaCl<sub>2</sub>, 10mM DTT, 50 uM DSS, 0.02% NaN<sub>3</sub>, 1X Proteinase Inhibitors, 5% D<sub>2</sub>O<br> | ||
pH 5.0, 50 | MJ004 50mM NH<sub>4</sub>OAc, pH 5.0, 10mM DTT, 50mM Arginine, 50 uM DSS, 0.02% NaN<sub>3</sub>, 1X Proteinase inhibitors, 5% D<sub>2</sub>O | ||
pH | MJ005 50mM NH<sub>4</sub>OAc, pH 5.0, 10mM DTT, 5% Acetonitrile, 50 uM DSS, 0.02% NaN<sub>3</sub>, 1X Proteinase inhibitors, 5% D<sub>2</sub>O | ||
pH 6.0, 50 | MJ006 50mM MES, pH 6.0, 10mM DTT, 50mM Arginine, 50 uM DSS, 0.02% NaN<sub>3</sub>, 1X Proteinase inhibitors, 5% D<sub>2</sub>O | ||
pH 6.5, | MJ007 50mM MES, pH 6.0, 10mM DTT, 5% Acetonitrile, 50 uM DSS, 0.02% NaN<sub>3</sub>, 1X Proteinase inhibitors, 5% D<sub>2</sub>O | ||
pH 6.5, | MJ008 25mM Na<sub>2</sub>PO<sub>4</sub>, pH 6.5, 450mM NaCl, 10mM DTT, 20uM ZnSO<sub>4</sub>, 50 uM DSS, 0.02% NaN<sub>3</sub>, 1X Proteinase inhibitors, 5% D<sub>2</sub>O | ||
pH 6.5, | MJ009 20mM MES, pH 6.5, 100mM NaCl, 5% Acetonitrile, 10mM DTT, 50 uM DSS, 0.02% NaN<sub>3</sub>, 1X Proteinase Inhibitors, 5% D<sub>2</sub>O | ||
pH 6.5, | MJ010 20mM MES, pH 6.5, 100mM NaCl, 50mM Arginine, 10mM DTT, 50 uM DSS, 0.02% NaN<sub>3</sub>, 1X Proteinase Inhibitors, 5% D<sub>2</sub>O | ||
pH 6.5, | MJ011 20mM MES, pH 6.5, 100mM NaCl, 1% Zwitter, 10mM DTT, 50 uM DSS, 0.02% NaN<sub>3</sub>, 1X Proteinase Inhibitors, 5% D<sub>2</sub>O | ||
< | MJ012 20mM MES, pH 6.5, 100mM NaCl, 50uM ZnSO4, 10mM DTT, 50 uM DSS, 0.02% NaN<sub>3</sub>, 1X Proteinase Inhibitors, 5% D<sub>2</sub>O | ||
Low Salt 10mM Tris-HCl, pH 7.5, 5mM DTT, 100mM NaCl , 0.02% NaN<sub>3</sub>, 50 uM DSS, 1X Proteinase Inhibitors, 5% D<sub>2</sub>O<br> | |||
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==== '''Abbreviations:''' ==== | ==== '''Abbreviations:''' ==== | ||
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DTT: Dithiothreitol | DTT: Dithiothreitol | ||
Zwitter: ZWITTERAGENT<sup>®</sup> 3-12 Detergent cat. | Zwitter: ZWITTERAGENT<sup>®</sup> 3-12 Detergent [cat.693015](CALBIOCHEM) | ||
MES: 2-(''N''-morpholino)ethanesulfonic acid | MES: 2-(''N''-morpholino)ethanesulfonic acid | ||
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Tris: tris(hydroxymethyl)aminomethane; | Tris: tris(hydroxymethyl)aminomethane; | ||
Protease | Protease inhibitors: Protease inhibitor cocktail tablets cat. 11836170001 (ROCHE); | ||
DSS: 2,2-Dimethyl-2-silapentane-5-sulfonic acid | |||
==== <br> <br> References ==== | ==== <br> <br> References ==== | ||
<references /> |
Latest revision as of 23:01, 26 November 2012
Buffer content plays a critical role in protein sample stability. Buffer optimization may be used to improve sample stability to avoid the following issues:
- slow precipitation
- mixture of folded and unfolded protein
- aggregation problems
- multiple populations (too many peaks) for other reasons
- and many other reasons
At Rutger’s University, NMR samples with promising spectra in the initial pH 6.5, 200 mM NaCl buffer are screened by 1H-15N HSQC spectra after exchanging into 13 commonly used screening buffers (listed below). Exchange is performed using by a desalting column and NMR screening is done with a Bruker MicroCryoprobe.[1]
NMR screening and optimization buffers:
MJ001 20mM MES, pH 6.5, 100mM NaCl, 5mM CaCl2, 10mM DTT, 50 uM DSS, 0.02% NaN3, 1x Proteinase Inhibitors, 5% D2O
MJ002 20mM NH4OAc, pH 5.5, 100mM NaCl, 5mM CaCl2, 10mM DTT, 50 uM DSS, 0.02% NaN3, 1X Proteinase Inhibitors, 5% D2O
MJ003 20mM NH4OAc, pH 4.5, 100mM NaCl, 5mM CaCl2, 10mM DTT, 50 uM DSS, 0.02% NaN3, 1X Proteinase Inhibitors, 5% D2O
MJ004 50mM NH4OAc, pH 5.0, 10mM DTT, 50mM Arginine, 50 uM DSS, 0.02% NaN3, 1X Proteinase inhibitors, 5% D2O
MJ005 50mM NH4OAc, pH 5.0, 10mM DTT, 5% Acetonitrile, 50 uM DSS, 0.02% NaN3, 1X Proteinase inhibitors, 5% D2O
MJ006 50mM MES, pH 6.0, 10mM DTT, 50mM Arginine, 50 uM DSS, 0.02% NaN3, 1X Proteinase inhibitors, 5% D2O
MJ007 50mM MES, pH 6.0, 10mM DTT, 5% Acetonitrile, 50 uM DSS, 0.02% NaN3, 1X Proteinase inhibitors, 5% D2O
MJ008 25mM Na2PO4, pH 6.5, 450mM NaCl, 10mM DTT, 20uM ZnSO4, 50 uM DSS, 0.02% NaN3, 1X Proteinase inhibitors, 5% D2O
MJ009 20mM MES, pH 6.5, 100mM NaCl, 5% Acetonitrile, 10mM DTT, 50 uM DSS, 0.02% NaN3, 1X Proteinase Inhibitors, 5% D2O
MJ010 20mM MES, pH 6.5, 100mM NaCl, 50mM Arginine, 10mM DTT, 50 uM DSS, 0.02% NaN3, 1X Proteinase Inhibitors, 5% D2O
MJ011 20mM MES, pH 6.5, 100mM NaCl, 1% Zwitter, 10mM DTT, 50 uM DSS, 0.02% NaN3, 1X Proteinase Inhibitors, 5% D2O
MJ012 20mM MES, pH 6.5, 100mM NaCl, 50uM ZnSO4, 10mM DTT, 50 uM DSS, 0.02% NaN3, 1X Proteinase Inhibitors, 5% D2O
Low Salt 10mM Tris-HCl, pH 7.5, 5mM DTT, 100mM NaCl , 0.02% NaN3, 50 uM DSS, 1X Proteinase Inhibitors, 5% D2O
Abbreviations:
DTT: Dithiothreitol
Zwitter: ZWITTERAGENT® 3-12 Detergent [cat.693015](CALBIOCHEM)
MES: 2-(N-morpholino)ethanesulfonic acid
Tris: tris(hydroxymethyl)aminomethane;
Protease inhibitors: Protease inhibitor cocktail tablets cat. 11836170001 (ROCHE);
DSS: 2,2-Dimethyl-2-silapentane-5-sulfonic acid
References
- ↑ Rossi, P. et. al. (2010). "A microscale protein NMR sample screening pipeline." J. Biomol. NMR, 46, 11-22.