Timeline for Does pH affect Michaelis constant?
Current License: CC BY-SA 3.0
9 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jun 4, 2017 at 14:27 | history | tweeted | twitter.com/StackBiology/status/871372772605403136 | ||
| May 28, 2017 at 13:31 | comment | added | Zahra | This paper might help you: Current IUBMB recommendations on enzyme nomenclature and kinetics | |
| Aug 25, 2015 at 15:28 | comment | added | wswr | Actually now that I think about it: I was confusing Michaelis-Menten constant with specific activity. My calculation was invalid. At pH 6.3, the specific activity is high, and the Km value is 34. The Km I got at pH is 21.5, but according to the paper, at pH 7, the specific activity is lower, which mean the Km should be higher. Can it can be assumed that the higher the Km, the lower the specific activity, and vice versa? | |
| Aug 21, 2015 at 19:45 | comment | added | WYSIWYG | @wswr No that assumption is not valid because the relationship between Km and pH can be non-linear and vary between different enzymes. | |
| Aug 21, 2015 at 19:44 | comment | added | wswr | Thanks for your reply. But is there an equation or method to calculate the relationship between Km and pH? If there isn't, was my calculation valid? I want to verify that if pH = 6.3 and Km =34, then Km must equal twenty-something at pH 7. | |
| Aug 21, 2015 at 19:01 | history | edited | WYSIWYG |
edited tags
|
|
| Aug 21, 2015 at 18:49 | answer | added | WYSIWYG | timeline score: 5 | |
| Aug 21, 2015 at 18:46 | comment | added | AMR | A very brief answer is yes, pH levels almost always effect enzyme efficiency. An example is lysosomal enzymes which are optimally active in the acidic environment of the lysosome, but are ineffective in the near neutral pH of the cytosol. This protects the cell should a lysosome rupture; the enzymes will not digest the cell itself. From the wikipedia article "The value of K_\mathrm{M} is dependent on both the enzyme and the substrate, as well as conditions such as temperature and pH.". And try not to forget Maud Menten. | |
| Aug 21, 2015 at 18:07 | history | asked | wswr | CC BY-SA 3.0 |