TY - JOUR
T1 - Studies on the properties of chemically modified actin III. Carbethoxylation
AU - Mühlrad, A.
AU - Hegyi, G.
AU - Horányi, M.
PY - 1969/5/20
Y1 - 1969/5/20
N2 - Diethylpyrocarbonate was used for the specific carbethoxylation of the histidyl residues of G- and F-actins. The characteristic properties of carbethoxylated actins were studied. The extent of carbethoxylation depended on the actin to reagent ratio, and equal numbers of histidyl residues were carbethoxylated in G- and F-actins. The number of tyrosine and SH groups did not change on diethylpyrocarbonate treatment. 30% of the bound nucleotide of G-actin was removed, whereas a high degree of carbethoxylation did not change the bound nucleotide of F-actin. The characteristic properties of F-actin (viscosity, repolymerizability, actomyosin formation, activation of myosin ATPase) were not altered by the treatment even on carbethoxylation of 70% of the histidyl residues. The characteristic properties of G-actin (polymerizability, actomyosin formation and activation of myosin ATPase) were almost lost on carbethoxylation of about half the histidyl residues. The treatment did not change the helix content of G-actin (the 233-mμ Cotton effect). These results lead to the assumption that the histidyl residues, which have some role in determining the characteristic properties of actin, are buried in F-actin.
AB - Diethylpyrocarbonate was used for the specific carbethoxylation of the histidyl residues of G- and F-actins. The characteristic properties of carbethoxylated actins were studied. The extent of carbethoxylation depended on the actin to reagent ratio, and equal numbers of histidyl residues were carbethoxylated in G- and F-actins. The number of tyrosine and SH groups did not change on diethylpyrocarbonate treatment. 30% of the bound nucleotide of G-actin was removed, whereas a high degree of carbethoxylation did not change the bound nucleotide of F-actin. The characteristic properties of F-actin (viscosity, repolymerizability, actomyosin formation, activation of myosin ATPase) were not altered by the treatment even on carbethoxylation of 70% of the histidyl residues. The characteristic properties of G-actin (polymerizability, actomyosin formation and activation of myosin ATPase) were almost lost on carbethoxylation of about half the histidyl residues. The treatment did not change the helix content of G-actin (the 233-mμ Cotton effect). These results lead to the assumption that the histidyl residues, which have some role in determining the characteristic properties of actin, are buried in F-actin.
UR - http://www.scopus.com/inward/record.url?scp=0014518015&partnerID=8YFLogxK
U2 - 10.1016/0005-2795(69)90240-2
DO - 10.1016/0005-2795(69)90240-2
M3 - ???researchoutput.researchoutputtypes.contributiontojournal.article???
C2 - 4240021
AN - SCOPUS:0014518015
SN - 0005-2795
VL - 181
SP - 184
EP - 190
JO - BBA - Protein Structure
JF - BBA - Protein Structure
IS - 1
ER -