Purification and characterization of phosphorylase a from human platelets

P. Gergely, Alan G. Castle, Neville Crawford

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

1. 1. Platelet phosphorylase a was isolated from human platelets by 5'-AMP-Sepharose 4B affinity chromatography to give two peaks of enzyme activity. The specific activities of the two peaks [I and II] were 24 U/mg and 45 U/mg corresponding to 400- and 800-fold purification with respect to the activity in the homogenate supernatant. The molecular weight of the purified enzyme was estimated by Na dodecyl sulphate polyacrylamide gel electrophoresis to be a single component with a molecular weight of 95,000. 2. 2. On the basis of enzyme activity measured in the presence of various ligands Peak I proved to be a partially phosphorylated, hybrid phosphorylase. 3. 3. The kinetic constants for the dephosphorylation of Peak I and Peak II phosphorylase were compared and showed the same Vmax with K = 9 μM and 4μM, respectively. 4. 4. Nucleotides (AMP, IMP, ADP) inhibited the dephosphorylation of platelet phosphorylase a. Glucose. glucose-6-phosphate and caffeine decreased this inhibition.

Original languageEnglish
Pages (from-to)807-814
Number of pages8
JournalInternational Journal of Biochemistry
Volume10
Issue number10
DOIs
Publication statusPublished - 1979

Fingerprint

Phosphorylase a
Platelets
Purification
Phosphorylases
Blood Platelets
Enzyme activity
Enzymes
Molecular Weight
Molecular weight
Affinity chromatography
Inosine Monophosphate
Glucose-6-Phosphate
Adenosine Monophosphate
Caffeine
Electrophoresis
Affinity Chromatography
Sepharose
Adenosine Diphosphate
Polyacrylamide Gel Electrophoresis
Nucleotides

ASJC Scopus subject areas

  • Biochemistry

Cite this

Purification and characterization of phosphorylase a from human platelets. / Gergely, P.; Castle, Alan G.; Crawford, Neville.

In: International Journal of Biochemistry, Vol. 10, No. 10, 1979, p. 807-814.

Research output: Contribution to journalArticle

Gergely, P. ; Castle, Alan G. ; Crawford, Neville. / Purification and characterization of phosphorylase a from human platelets. In: International Journal of Biochemistry. 1979 ; Vol. 10, No. 10. pp. 807-814.
@article{2710965775f549cf9b7ea1df620a8c00,
title = "Purification and characterization of phosphorylase a from human platelets",
abstract = "1. 1. Platelet phosphorylase a was isolated from human platelets by 5'-AMP-Sepharose 4B affinity chromatography to give two peaks of enzyme activity. The specific activities of the two peaks [I and II] were 24 U/mg and 45 U/mg corresponding to 400- and 800-fold purification with respect to the activity in the homogenate supernatant. The molecular weight of the purified enzyme was estimated by Na dodecyl sulphate polyacrylamide gel electrophoresis to be a single component with a molecular weight of 95,000. 2. 2. On the basis of enzyme activity measured in the presence of various ligands Peak I proved to be a partially phosphorylated, hybrid phosphorylase. 3. 3. The kinetic constants for the dephosphorylation of Peak I and Peak II phosphorylase were compared and showed the same Vmax with K = 9 μM and 4μM, respectively. 4. 4. Nucleotides (AMP, IMP, ADP) inhibited the dephosphorylation of platelet phosphorylase a. Glucose. glucose-6-phosphate and caffeine decreased this inhibition.",
author = "P. Gergely and Castle, {Alan G.} and Neville Crawford",
year = "1979",
doi = "10.1016/0020-711X(79)90053-3",
language = "English",
volume = "10",
pages = "807--814",
journal = "International Journal of Biochemistry and Cell Biology",
issn = "1357-2725",
publisher = "Elsevier Limited",
number = "10",

}

TY - JOUR

T1 - Purification and characterization of phosphorylase a from human platelets

AU - Gergely, P.

AU - Castle, Alan G.

AU - Crawford, Neville

PY - 1979

Y1 - 1979

N2 - 1. 1. Platelet phosphorylase a was isolated from human platelets by 5'-AMP-Sepharose 4B affinity chromatography to give two peaks of enzyme activity. The specific activities of the two peaks [I and II] were 24 U/mg and 45 U/mg corresponding to 400- and 800-fold purification with respect to the activity in the homogenate supernatant. The molecular weight of the purified enzyme was estimated by Na dodecyl sulphate polyacrylamide gel electrophoresis to be a single component with a molecular weight of 95,000. 2. 2. On the basis of enzyme activity measured in the presence of various ligands Peak I proved to be a partially phosphorylated, hybrid phosphorylase. 3. 3. The kinetic constants for the dephosphorylation of Peak I and Peak II phosphorylase were compared and showed the same Vmax with K = 9 μM and 4μM, respectively. 4. 4. Nucleotides (AMP, IMP, ADP) inhibited the dephosphorylation of platelet phosphorylase a. Glucose. glucose-6-phosphate and caffeine decreased this inhibition.

AB - 1. 1. Platelet phosphorylase a was isolated from human platelets by 5'-AMP-Sepharose 4B affinity chromatography to give two peaks of enzyme activity. The specific activities of the two peaks [I and II] were 24 U/mg and 45 U/mg corresponding to 400- and 800-fold purification with respect to the activity in the homogenate supernatant. The molecular weight of the purified enzyme was estimated by Na dodecyl sulphate polyacrylamide gel electrophoresis to be a single component with a molecular weight of 95,000. 2. 2. On the basis of enzyme activity measured in the presence of various ligands Peak I proved to be a partially phosphorylated, hybrid phosphorylase. 3. 3. The kinetic constants for the dephosphorylation of Peak I and Peak II phosphorylase were compared and showed the same Vmax with K = 9 μM and 4μM, respectively. 4. 4. Nucleotides (AMP, IMP, ADP) inhibited the dephosphorylation of platelet phosphorylase a. Glucose. glucose-6-phosphate and caffeine decreased this inhibition.

UR - http://www.scopus.com/inward/record.url?scp=0018579526&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0018579526&partnerID=8YFLogxK

U2 - 10.1016/0020-711X(79)90053-3

DO - 10.1016/0020-711X(79)90053-3

M3 - Article

VL - 10

SP - 807

EP - 814

JO - International Journal of Biochemistry and Cell Biology

JF - International Journal of Biochemistry and Cell Biology

SN - 1357-2725

IS - 10

ER -