Selective reduction of the disulfide bonds of ovine placental lactogen.
Reduction and carbamidomethylation of two of the three disulfide bridges of ovine placental lactogen was accomplished by the use of 20-fold molar excess of dithiothreitol over protein disulfide content. The derivative retained its binding capacity to somatogenic as well as lactogenic rat liver receptors, although the latter was somewhat diminished. The two disulfide bonds exposed to the reducing agent are those located near the carboxy- and amino-terminus, while the larger loop remained intact after reduction. This behaviour is similar to that of bovine growth hormone, where the larger loop was also more resistant to reduction.
Caridad
J J
JJ
Institute of Biochemistry and Biophysico-chemistry (UBA-CONICET), Faculty of Pharmacy and Biochemistry, Buenos Aires, Argentina.
Wolfenstein-Todel
C
C
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D001667:Binding, Competitive; D004220:Disulfides / Q000378:metabolism*; D004229:Dithiothreitol; D013006:Growth Hormone / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D010084:Oxidation-Reduction; D010446:Peptide Fragments / Q000032:analysis / Q000378:metabolism; D010928:Placental Lactogen / Q000032:analysis / Q000378:metabolism*; D051381:Rats; D018000:Receptors, Peptide; D011981:Receptors, Prolactin / Q000378:metabolism; D011986:Receptors, Somatotropin / Q000378:metabolism; D012756:Sheep
D000596:Amino Acids; D004220:Disulfides; D010446:Peptide Fragments; D018000:Receptors, Peptide; D011981:Receptors, Prolactin; D011986:Receptors, Somatotropin; C028202:placental lactogen receptor; D013006:Growth Hormone; D010928:Placental Lactogen; D004229:Dithiothreitol