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Updated: Aug 14, 2026

Synthesis and Mass Spectrometry Analysis of Oligo-peptoids
Published on: February 21, 2018
The composition, structure and origin of proteose-peptone component 8F of bovine milk
Abstract:
Proteose-peptone component 8F (or '8-fast') has been prepared from bovine milk. Sedimentation equilibrium analysis, polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate and gel filtration in urea-containing buffers all gave molecular weight values between 3300 and 3900. The N-terminal sequence was found to be Arg-Glu- by dansylation and Edman degradation. Hydrazinolysis released lysine from the C-terminus. A mixture of carboxypeptidases A and B showed that the C-terminal sequence was -Thr-(Arg,Ile,Asn)-Lys. The phosphate content was 3.8 mol/mol and was completely released by a short alkaline hydrolysis indicating linkage to serine. This and all other aspects of the composition were entirely consistent with the identification of this proteosepeptone as residues 1--28 of the beta-casein molecule. This identity was confirmed by a peptide mapping procedure. Thus proteose-peptone component 8F represents the N-terminal fragment when the gamma1-caseins are formed by proteolysis of beta-casein.
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