Entitic catalytic activity (entitic cat.act.)

Abbreviation

Entitic cat.act.

Definition in words

Catalytic-activity of component B divided by number of system 1 in system 2

Alternative expression: Catalytic-activity of component B per system 1 in system 2

Note 1: Component B is a catalytic component

Definition by equation

Systematic terms

Entitic catalytic-activity of component B in system 2
Ratio scale
  • Value sets are positive numerical values
  • Algebraic operations are allowed (a=nb; a≠nb)
Numerical values from 0-∞

Unit

akat, fkat, pkat, nkat, µkat, mkat, U, pU, nU, etc.

Note 1: The correct unit is e.g. “akat/1” but “1” is omitted.

Note 2: Katal, “kat”, is recommended unit for catalytic-activity kind-of-quantity. (kat=mol/s)

Note 3: Enzyme unit, “U”, is acceptable for use (e.g. U, kU) but it is recommended to use katal. (U=µmol/min)

Special rule(s) in the NPU syntax

The catalytic component (component B) is termed according to the International Enzyme Nomenclature (see Medical and metrological vocabulary).

“Procedure” is stated in the specification to the kind-of-property in the NPU definition.

“Procedure” indicates that the measurement procedure must be stated somewhere else than the NPU code and there may be difficulties in comparing values for the same NPU code.

Reference

Ferard G, Dybkaer R, Fuentes-Arderiu X. Compendium of Terminology and Nomenclature of Properties in Clinical Laboratory Sciences : Recommendations 2016. 1 ed: Royal Society of Chemistry; 2016. 182 p.

Laboratory field

Examples

Clinical Chemistry

Example 1
Generic abbreviated form NPU57414 Ercs(B)—Pyruvate kinase; entitic cat.act.(37 °C; proc.) = ? pU
Full form with a result NPU57414 Erythrocytes(Blood)—Pyruvate kinase; entitic catalytic-activity(37 °C; procedure) = 44 pico Enzyme Unit
Abbreviated form with a result NPU57414 Ercs(B)—Pyruvate kinase; entitic cat.act.(37 °C; proc.) = 44 pU
Written expression The catalytic-activity of Pyruvate kinase divided by number of Erythrocytes in Mr. Smith’s blood is [44] pU. The measurement is performed at 37 °C according to a procedure defined by the laboratory.
Equation

Notes

Alternative written expression:

The catalytic-activity of Pyruvate kinase per Erythrocyte in Mr. Smith’s blood is [44] pU.

Example 2
Generic abbreviated form NPU03340 Ercs(B)—Pyruvate kinase; entitic cat.act.(37 °C; proc.) = ? akat
Full form with a result NPU03340 Erythrocytes(Blood)—Pyruvate kinase; entitic catalytic-activity(37 °C; procedure) = 25 attokatal
Abbreviated form with a result NPU03340 Ercs(B)—Pyruvate kinase; entitic cat.act.(37 °C; proc.) = 25 akat
Written expression The catalytic-activity of Pyruvate kinase divided by number of Erythrocytes in Mr. Smith’s blood is [25] akat. The measurement is performed at 37 °C according to a procedure defined by the laboratory.
Equation

Notes

Alternative written expression:

The catalytic-activity of Pyruvate kinase per Erythrocyte in Mr. Smith’s blood is [25] akat.

Molecular Biology and Genetics 

Example 3
Generic abbreviated form NPU57390 Ercs(B)—Glucose-6-phosphate dehydrogenase; entitic cat.act.(37 °C; proc.) = ? pU
Full form with a result NPU57390 Erythrocytes(Blood)—Glucose-6-phosphate dehydrogenase; entitic catatlytic-activity(37 °C; procedure) = 75 pico Enzyme Unit
Abbreviated form with a result NPU57390 Ercs(B)—Glucose-6-phosphate dehydrogenase; entitic cat.act.(37 °C; proc.) = 75 pU
Written expression The catalytic-activity of Glucose-6-phosphate dehydrogenase divided by number of Erythrocytes in Mr. Smith’s blood is [75] pU. The measurement is performed at 37 °C according to a procedure defined by the laboratory
Equation
 Notes

Alternative written expression:

The catalytic-activity of Glucose-6-phosphate dehydrogenase per Erythrocyte in Mr. Smith’s blood is [75] pU

Example 4
Generic abbreviated form NPU01080 Lymcs—Adenosine deaminase; entitic cat.act.(37 °C; proc.) = ? akat
Full form with a result NPU01080 Lymphocytes—Adenosine deaminase; entitic catalytic-activity(37 °C; procedure) = 100 attokatal
Abbreviated form with a result NPU01080 Lymcs—Adenosine deaminase; entitic cat.act.(37 °C; proc.) = 100 akat
Written expression The catalytic-activity of Adenosine deaminase divided by number of Mr. Smith’s Lymphocytes is [100] akat. The measurement is performed at 37 °C according to a procedure defined by the laboratory
Equation
 Notes

Alternative written expression:

The catalytic-activity of Adenosine deaminase per Mr. Smith’s Lymphocyte blood is [100] akat.

Reproduction and Fertility

Example 5
Generic abbreviated form NPU01069 Spmzoa—Acrosin; entitic cat.act.(37 °C; proc.) = ? akat
Full form with a result NPU01069 Spermatozoa—Acrosin; entitic catalytic-activity(37 °C; procedure) = 15 attokatal
Abbreviated form with a result NPU01069 Spmzoa—Acrosin; entitic cat.act.(37 °C; proc.) = 15 akat
Written expression The catalytic-activity of Acrosin divided by number of Mr. Smith’s spermatozoa is [15] akat. The measurement is performed at 37 °C according to a procedure defined by the laboratory.
Equation
Notes

Alternative written expression:

The catalytic-activity of Pyruvate kinase per Erythrocyte in Mr. Smith’s blood is [15] pU

Reference

  NPU database, https://www.ifcc.org/ifcc-scientific-division/sd-committees/c-npu/npusearch/ and http://www.labterm.dk/default.aspx
  • Kind-of-property

    • Nominal kind-of-property

    • Kind-of-quantity

      • Unitary kind-of-quantity

        • Rational unitary kind-of-quantity

          • Entitic catalytic activity

Reference

  • Dybkaer R. Concept system on ‘quantity’: formation and terminology. Accredit Qual Assur. 2013;18(3):253-60.
  • Dybkaer R. ISO terminological analysis of the VIM3 concepts ‘quantity’ and ‘kind-of-quantity’. Metrologia. 2010;47(3):127-34.
Date Term Note
1996-01-01 Entitic catalytic activity Term established