دورية أكاديمية
The binding of nucleotides and bivalent cations to the calcium-and-magnesium ion-dependent adenosine triphosphatase from rabbit muscle sarcoplasmic reticulum
| العنوان: | The binding of nucleotides and bivalent cations to the calcium-and-magnesium ion-dependent adenosine triphosphatase from rabbit muscle sarcoplasmic reticulum |
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| المؤلفون: | Yates, D W, Duance, V C |
| المصدر: | Biochemical Journal ; volume 159, issue 3, page 719-728 ; ISSN 0264-6021 |
| بيانات النشر: | Portland Press Ltd. |
| سنة النشر: | 1976 |
| مصطلحات موضوعية: | Cell Biology, Molecular Biology, Biochemistry |
| الوصف: | The binding of MgATP to purified Ca2+Mg2+-dependent adenosine triphosphatase from rabbit muscle sarcoplasmic reticulum was studied by using a flow-dialysis method. Phosphoryl-enzyme formation and catalytic activity were also measured, and all three processes demonstrated negative co-operativity, with half-saturation of all three parameters at a MgATP concentration of 40-50muM, and a Hill coefficient (h) of 0.8. The variation of the binding constant with with pH was measured and showed tighter binding of MgATP with increasing pH over the range 6.8-8.5. Binding parameters for ATP analogues were also measured. The binding of Ca2+ in the presence and absence of ATP analogues gave half saturation at a Ca2+ concentration of 1.2-1.3muM. Hill plots of Ca2+-binding data gave a slope of 0.8. These results show that the binding of MgATP and Ca2+ can occur in a random manner, with neither substrate influencing the affinity of the enzyme for the other. |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| DOI: | 10.1042/bj1590719 |
| الإتاحة: | https://doi.org/10.1042/bj1590719Test https://portlandpress.com/biochemj/article-pdf/159/3/719/569258/bj1590719.pdfTest |
| رقم الانضمام: | edsbas.92D88193 |
| قاعدة البيانات: | BASE |
| DOI: | 10.1042/bj1590719 |
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