Amino-terminal and carboxyl-terminal half-molecules of ovotransferrin: preparation by a novel procedure and their interactions.
The amino- (N-) and carboxyl- (C-)terminal half-molecules of ovotransferrin were prepared by a novel procedure. The trypsin-nicked ovotransferrin (Ikeda et al. (1985) FEBS Lett. 182, 305-309), in which the two half-molecules interact non-covalently forming a stable dimer, was purified by gel filtration and anion-exchange column chromatography. By subsequent cation-exchange chromatography, the nicked form was distinctly separated into an equivalent amount of the N-terminal and C-terminal half-molecules. Analyses of the N-terminal and C-terminal sequences indicated that the N-terminal and C-terminal half-molecules comprised the alignments of residues 1-332 and 342-686 of ovotransferrin, respectively. Anion-exchange chromatography, gel filtration chromatography, and non-denaturing polyacrylamide gel electrophoresis revealed that the isolated half-molecules had the ability to re-associate in solution. The contents of alpha-helix and beta-sheet of the two half-molecules, as determined by circular dichroism (CD) spectra, were very similar to those of intact ovotransferrin. No prominent alteration in the secondary structure of the two half-molecules was induced by the re-association.
Oe
H
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Research Institute for Food Science, Kyoto University, Uji.
Doi
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E
Hirose
M
M
D000596:Amino Acids / Q000302:isolation & purification*; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D002942:Circular Dichroism; D003207:Conalbumin / Q000032:analysis*; D004527:Egg Proteins / Q000032:analysis*; D004591:Electrophoresis, Polyacrylamide Gel; D008968:Molecular Conformation; D011487:Protein Conformation
D000596:Amino Acids; D004527:Egg Proteins; D003207:Conalbumin