ISSN:
1573-4943
Keywords:
Water buffalo
;
αs1-casein
;
β-casein
;
primary structure
;
phosphorylation sites
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract The primary structure of water buffalo αs1-casein and of β-casein A and B variants has been determined using a combination of mass spectrometry and Edman degradation procedures. The phosphorylated residues were localized on the tryptic phosphopeptides after performing a β-elimination/thiol derivatization. Water buffalo αs1-casein, resolved in three discrete bands by isoelectric focusing, was found to consist of a single protein containing eight, seven, or six phosphate groups. Compared to bovine αs1-casein C variant, the water buffalo αs1-casein presented ten amino acid substitutions, seven of which involved charged amino acid residues. With respect to bovine βA2-casein variant, the two water buffalo β-casein variants A and B presented four and five amino acid substitutions, respectively. In addition to the phosphoserines, a phosphothreonine residue was identified in variant A. From the phylogenetic point of view, both water buffalo β-casein variants seem to be homologous to bovine βA2-casein.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1020786503978
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