Enzyme activity converter
Convert between international units and katals: how fast an enzyme turns substrate into product.
That's about the same as a laboratory assay. That converts about 1.004×10¹⁶ molecules every second.
What it means
How fast does it work?
Activity depends on temperature, pH and substrate concentration, so figures are only comparable under the same assay conditions.
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Three things worth knowing
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1 U = 16.67 nkat
A micromole per minute is a sixtieth of a micromole per second, so the conversion is divide by 60 and shift the prefix.
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The katal arrived late
Proposed in 1972 and adopted into SI in 1999, it never displaced the international unit in clinical laboratories, where U/L is still printed on reports.
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Activity is not amount
Two samples with the same units of activity can hold very different amounts of enzyme, if one is more efficient than the other.
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Background
About activity units
One katal converts one mole of substrate per second, which is enormous. Laboratories use the older international unit: one micromole per minute, or 16.67 nanokatals.