The katal (symbol: kat) is the enzyme unit. Enzyme units are, however, still more commonly used than the katal in practice at present, especially in biochemistry.
The katal is not used to express the rate of a reaction; that is expressed in units of concentration per second (or moles per liter per second). Rather, it is used to express catalytic activity which is a property of the catalyst. The katal is invariant of the measurement procedure, but the numerical quantity value is not and depends on the experimental conditions. Therefore, in order to define the quantity of a catalyst, the rate of conversion of a defined chemical reaction is specified as mols reacted per second. One katal of trypsin, for example, is that amount of trypsin which breaks a mole of peptide bonds per second under specified conditions.
Definition
-
1 kat = 1 mol/s
SI multiples
SI multiples for katal (kat)
Submultiples
|
|
Multiples
|
Value
|
Symbol
|
Name
|
Value
|
Symbol
|
Name
|
10−1 kat
|
dkat
|
decikatal
|
101 kat
|
dakat
|
decakatal
|
10−2 kat
|
ckat
|
centikatal
|
102 kat
|
hkat
|
hectokatal
|
10−3 kat
|
mkat
|
millikatal
|
103 kat
|
kkat
|
kilokatal
|
10−6 kat
|
µkat
|
microkatal
|
106 kat
|
Mkat
|
megakatal
|
10−9 kat
|
nkat
|
nanokatal
|
109 kat
|
Gkat
|
gigakatal
|
10−12 kat
|
pkat
|
picokatal
|
1012 kat
|
Tkat
|
terakatal
|
10−15 kat
|
fkat
|
femtokatal
|
1015 kat
|
Pkat
|
petakatal
|
10−18 kat
|
akat
|
attokatal
|
1018 kat
|
Ekat
|
exakatal
|
10−21 kat
|
zkat
|
zeptokatal
|
1021 kat
|
Zkat
|
zettakatal
|
10−24 kat
|
ykat
|
yoctokatal
|
1024 kat
|
Ykat
|
yottakatal
|
Origin
The name katal has been used for decades and it became an official SI unit in 1999.
References
-
^ Nomenclature Committee of the International Union of Biochemistry (NC-IUB) (1979). "Units of Enzyme Activity". Eur. J. Biochem. 97 (2): 319–20.
External links
-
Unit "katal" for catalytic activity (IUPAC Technical Report) Pure Appl. Chem. Vol. 73, No. 6, pp. 927–931 (2001) [1]
-
René Dybkær (1 March 2002). "The Tortuous Road to the Adoption of katal for the Expression of Catalytic Activity by the General Conference on Weights and Measures". Clinical Chemistry 48 (3): 586–590.
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.