In:
Journal of Dairy Research, Cambridge University Press (CUP), Vol. 46, No. 2 ( 1979-04), p. 211-213
Abstract:
Using gel electrophoresis a genetic polymorphism of α s2 -casein (Cn) was discovered in individual milk samples from 2 bovine breeds of the eastern part of France (Vosgienne and Montbéliarde). The 3 observed phenotypes (Plate 1) are determined by 2 co-dominant alleles at an autosomal locus. The α s2 -Cn A variant was the only one known up to now in European breeds (reference variant) and ± s2 -Cn D is a new variant, whose bands overlap the β-casein A band at pH 8.6, and migrate faster than α s2 -Cn A at pH 3.0. The sequence of the polypeptide chain α s2 -Cn D differs from that of α s2 -Cn A by the deletion of a very acidic nonapeptide, which includes a cluster of 3 phosphoseryl residues. Due to the characteristics of the reference sequence, this deletion cannot be exactly located but it involves residues 50–58, or 51–59, or 52–60. A genetic analysis shows that locus α s2 -Cn is closely linked to the cluster α sl -Cn–β-Cn- K -Cn. The 4 casein species are thus synthesized by 4 closely linked loci.
Type of Medium:
Online Resource
ISSN:
0022-0299
,
1469-7629
DOI:
10.1017/S0022029900017052
Language:
English
Publisher:
Cambridge University Press (CUP)
Publication Date:
1979
detail.hit.zdb_id:
2000010-8
SSG:
22
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