Catal
Physical unit | |
---|---|
Unit name | Catal |
Unit symbol | |
Physical quantity (s) | catalytic activity |
Formula symbol | |
dimension | |
system | International system of units |
In SI units | |
Derived from | Mol , second |
The katal ( kat ) is a special name for the SI unit of the catalytic activity and thus the enzyme activity .
A katal means one mole of substrate turnover per second and can be converted into the previously used enzyme unit (U) as follows :
In Germany, the katal has been the legal unit in metrology since October 3, 2009 .
In clinical chemistry , catalytic activities per volume are measured under standard conditions and then serve as a measure of the enzyme concentration. The unit (i.e. enzyme unit per liter) is still used for this use .
history
The name Katal was proposed in 1972 by the enzyme commission of the IUB ( International Union of Biochemistry ) as the SI unit of measurement for enzyme activity. It was included in the catalog of derived SI units in 1999.
literature
- Peter Kurzweil: The Vieweg unit lexicon: terms, formulas and constants from natural sciences, technology and medicine . Vieweg + Teubner Verlag , Wiesbaden 2013, ISBN 978-3-322-83211-5 , p. 206 .
Individual evidence
- ↑ to note: the katal indicates the amount of enzyme as a catalyst, but not the amount of substrate; a katal means: enough enzyme that one mole of substrate per second can be converted with it as a catalyst ; the amount of substance of the enzyme can differ considerably from 1 mol: x mol of enzyme for 1 mol of substrate corresponds to 1 cat.
- ↑ Third ordinance amending the Units Ordinance of September 25, 2009 ( Federal Law Gazette I p. 3169 ).
- ^ Resolution 12 of the 21st meeting of the CGPM (1999) ( online , accessed September 13, 2019).