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Lidstrom:Buffers: Difference between revisions
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** Phosphate being an important metabolite is known to inhibit a number of enzymes; e.g. kinases, dehydrogenases, carboxypeptidase, fumarase, urease, aryl sulphatase, adenoside deaminase, phosphoglucomutase, and other enzymes involving phosphate esters. | ** Phosphate being an important metabolite is known to inhibit a number of enzymes; e.g. kinases, dehydrogenases, carboxypeptidase, fumarase, urease, aryl sulphatase, adenoside deaminase, phosphoglucomutase, and other enzymes involving phosphate esters. | ||
** On the other hand, it may stabilize enzymes, e.g. phosphoribosepyrophosphate synthase. | ** On the other hand, it may stabilize enzymes, e.g. phosphoribosepyrophosphate synthase. | ||
* '''Pyrophosphate | * '''Pyrophosphate''' | ||
** | ** Pyrophosphate buffers also precipitate polyvalent cations and have a tendency to form complexes. Like phosphate it is also a metabolite and may affect certain enzymes. | ||
* '''Imidazole'' | |||
** Imidazole has on occasions been used where phosphate is not acceptable, since both have similar buffering ranges. It is not generally a good alternative, since it is reactive, unstable, and also complexes with divalent metal ions. Mops or Bes might be a better alternative. | |||
* '''Borate''' | |||
** Borate has the disadvantage of complexing with vic diols, which included many carbohydrates and the ribose moitey of nucleotides. It would be best avoided when assaying enzymes using NAD(P) or other nucleotides. | |||
== Resources== | == Resources== | ||
