TY - JOUR
T1 - Heterogeneity of SH group in sarcoplasmic reticulum
AU - Hidalgo, Cecilia
AU - Thomas, David D.
PY - 1977/10/24
Y1 - 1977/10/24
N2 - The incorporation of [14C] N-ethylmaleimide reveals fast and slow-reacting sulfhydryl groups in sarcoplasmic reticulum. Two proteins react with the label: a fast-reacting glycoprotein recently isolated (Ikemoto, Cucchiaro and Garcia (1976) J. Cell Biol.70, 290a), and the Ca2+-ATPase. Labeling sarcoplasmic reticulum with a maleimide spin label gives a similar pattern. The spectra of maleimide-spin-labeled sarcoplasmic reticulum have both 'strongly' and 'weakly' immobilized components. Maleimide-spin-labeled purified Ca2+-ATPase, or sarcoplasmic reticulum labeled first with N-ethylmaleimide, and then with maleimide spin label, show spectra devoid of the 'weakly' immobilized component; the latter is enhanced in partially purified glycoprotein obtained from spin-labeled sarcoplasmic reticulum. This indicates that spectra from maleimide-spin-labeled sarcoplasmic reticulum do not reflect exclusively the state of the Ca2+-ATPase enzyme.
AB - The incorporation of [14C] N-ethylmaleimide reveals fast and slow-reacting sulfhydryl groups in sarcoplasmic reticulum. Two proteins react with the label: a fast-reacting glycoprotein recently isolated (Ikemoto, Cucchiaro and Garcia (1976) J. Cell Biol.70, 290a), and the Ca2+-ATPase. Labeling sarcoplasmic reticulum with a maleimide spin label gives a similar pattern. The spectra of maleimide-spin-labeled sarcoplasmic reticulum have both 'strongly' and 'weakly' immobilized components. Maleimide-spin-labeled purified Ca2+-ATPase, or sarcoplasmic reticulum labeled first with N-ethylmaleimide, and then with maleimide spin label, show spectra devoid of the 'weakly' immobilized component; the latter is enhanced in partially purified glycoprotein obtained from spin-labeled sarcoplasmic reticulum. This indicates that spectra from maleimide-spin-labeled sarcoplasmic reticulum do not reflect exclusively the state of the Ca2+-ATPase enzyme.
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U2 - 10.1016/0006-291X(77)91417-6
DO - 10.1016/0006-291X(77)91417-6
M3 - Article
C2 - 200229
AN - SCOPUS:0017688686
VL - 78
SP - 1175
EP - 1182
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
SN - 0006-291X
IS - 4
ER -