Effects of substrate concentration on results of determination of prostatic acid phosphatase with thymolphthalein monophosphate.

1983 ◽  
Vol 29 (1) ◽  
pp. 148-151 ◽  
Author(s):  
A Kessner ◽  
E J Woodard ◽  
G N Bowers
Keyword(s):  
Catalytic Activity ◽  
Acid Phosphatase ◽  
Substrate Concentration ◽  
Prostatic Acid Phosphatase ◽  
Combined Effects ◽  
Mixed Substrate ◽  
Order Of Magnitude ◽  
Substrate Concentrations

Abstract The relation between concentration of thymolphthalein monophosphate substrate and catalytic activity was investigated for the determination of prostatic acid phosphatase. This study, an extension of previously reported work (Clin. Chem. 27: 1372, 1981), shows that lot-to-lot variation in purity of thymolphthalein monophosphate preparations is reflected in substrate-velocity curves. Plateau regions in these curves at 1.5-2.5 g/L result from the combined effects of (a) substrate concentrations that are an order of magnitude below Km and (b) a further decrease in available substrate caused by formation of substrate aggregates in the presence of serum. To simplify the identification of superior lots of thymolphthalein monophosphate, we give a mixed-substrate protocol for testing different lots.

scholarly journals The determination of binding parameters when the total and free substrate concentrations are not approximately equal

1979 ◽  
Vol 179 (3) ◽  
pp. 697-700 ◽  
Author(s):  
N Gains
Keyword(s):  
Substrate Concentration ◽  
Graphical Method ◽  
Enzyme Concentration ◽  
Binding Parameters ◽  
Free Concentration ◽  
Equilibrium Binding ◽  
Substrate Concentrations

By using a standard graphical method values of Km and V may be found that are independent of the conditions and assumptions that the total substrate concentration approximates to its free concentration and that Km is much larger than the enzyme concentration. The procedure is also applicable to the determination of equilibrium binding parameters of a ligand to a macromolecule.

Is the determination of prostatic acid phosphatase still worthwhile in prostate cancer patients?

1997 ◽  
Vol 3 (2) ◽  
pp. 47-50
Author(s):  
Walter L Strohmaier ◽  
Andreas Zumbraegel ◽  
Lennart Koschella ◽  
K Horst Bichler
Keyword(s):  
Prostate Cancer ◽  
Acid Phosphatase ◽  
Cancer Patients ◽  
Prostatic Acid Phosphatase

Influence of substrate concentration on the activation of transketolase, aspartate aminotransferase, and glutathione reductase by coenzymes.

1984 ◽  
Vol 30 (1) ◽  
pp. 143-144
Author(s):  
J C Hafkenscheid ◽  
C M van Dijk
Keyword(s):  
Catalytic Activity ◽  
Glutathione Reductase ◽  
Aspartate Aminotransferase ◽  
Substrate Concentration ◽  
Activity Concentrations ◽  
Influence Of Substrate ◽  
Underlying Mechanisms ◽  
Substrate Concentrations

Abstract We investigated the mechanism by which the three most commonly measured enzymes in erythrocytes are activated by their respective coenzymes by determining the catalytic activity concentrations of transketolase (EC 2.2.1.1), aspartate aminotransferase (EC 2.6.1.1), and glutathione reductase (EC 1.6.4.2) in relation to various substrate concentrations. We conclude that the underlying mechanisms by which the enzymes are activated are not the same.

Development of a stable reference material for prostatic acid phosphatase.

1984 ◽  
Vol 30 (8) ◽  
pp. 1327-1331 ◽  
Author(s):  
P H Duncan ◽  
R L Van Etten ◽  
M L MacNeil ◽  
L M Shaw
Keyword(s):  
Catalytic Activity ◽  
Acid Phosphatase ◽  
Reference Material ◽  
Sodium Acetate ◽  
Seminal Fluid ◽  
Reference Method ◽  
Prostatic Acid Phosphatase ◽  
Two Dimensional ◽  
Two Dimensional Electrophoresis ◽  
Dimensional Electrophoresis

Abstract We describe the development of a stable reference material for prostatic acid phosphatase, derived from human prostatic tissue and human seminal fluid. The enzyme was purified by an L-tartramic acid affinity-chromatography technique. Two-dimensional electrophoresis revealed essentially no contaminating proteins, and specific tests revealed no contaminating enzymes. The preparations, in a matrix containing 30 g of human serum albumin and 0.1 mol of sodium acetate per liter, pH 6.0, were studied with respect to stability of both catalytic activity and immunological identity. We conclude that the preparations from either source are satisfactorily stable, and that either is acceptable for use in preparing clinical reference materials. These materials will be used in developing a reference method.

scholarly journals A Reference Preparation of Human Prostatic Acid Phosphatase: Purification, Characterization and Field Trials

1992 ◽  
Vol 29 (2) ◽  
pp. 176-183 ◽  
Author(s):  
J M Francis ◽  
D W Moss ◽  
Elisabeth Colinet ◽  
D H Calam ◽  
D G Bullock
Keyword(s):  
Catalytic Activity ◽  
Acid Phosphatase ◽  
Pure State ◽  
Prostatic Acid Phosphatase ◽  
Field Trials ◽  
Time Dependent ◽  
Albumin Solution ◽  
Accelerated Degradation ◽  
Degradation Tests ◽  
Reference Preparation

Acid phosphatase has been prepared in an apparently pure state by affinity chromatography from human prostatic tissue. When dissolved in an acidic albumin solution, lyophilized and stored at −20°C for up to 2 years, no time-dependent loss of catalytic activity was detectable in the reconstituted material. Accelerated degradation tests also predicted complete stability. A preliminary distribution of the lyophilized preparation to 143 laboratories confirmed its robustness and demonstrated its potential usefulness as a calibrant to unify the results of different methods of measuring acid phosphatase activity.

Automated Determination of Acid Phosphatase

1966 ◽  
Vol 12 (4) ◽  
pp. 226-233 ◽  
Author(s):  
Bernard Klein ◽  
Morris Oklander ◽  
Stanley Morgenstern
Keyword(s):  
Acid Phosphatase ◽  
Human Serum ◽  
Phosphatase Activity ◽  
Acid Phosphatase Activity ◽  
Prostatic Acid Phosphatase ◽  
Biological Materials ◽  
Automated System ◽  
Automated Determination ◽  
Serum Acid Phosphatase

Abstract A procedure is presented for the automated determination of acid phosphatase activity in biological materials using the Robot Chemist. Although either phenylphosphate and α-naphthylphosphate may be used as substrate in this analysis, the procedure is described in detail for serum acid phosphatase using α-naphthylphosphate in 0.1 M citrate, pH 5.2, since this substrate is more selective for prostatic acid phosphatase in human serum. Enzymically generated aα- naphthol is determined by the Emerson reaction (alkaline aminoantipyrine and ferricyanide), modified for use with this automated system. Correlations are presented between the results obtained on the Robot Chemist and the identical procedure developed for the AutoAnalyzer.

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