Biochemical, molecular and physiological characterization of a new β-casein variant detected in Korean Cattle

✍ Scribed by S K Han; Y C Shin; H D Byun

• Book ID: 104457304
• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 72 KB
• Volume: 31
• Category: Article
• ISSN: 0268-9146
• DOI: 10.1046/j.1365-2052.2000.00582.x

✦ Synopsis

Summary

There are seven known genetic variants of bovine β‐casein (β‐CN) ‐ A1, A2, A3, B, C, D and E. In this study, we identified a new genetic variant (named β‐CN H) which migrates slower than the other variants in acidic starch gel electrophoresis. We confirmed through protein and DNA sequence analyses that the H variant differs at five residues from the A2 sequence: Arg25/Cys, Leu88/Ile, Gln117/Glu, Glu175/Gln and Gln195/Glu. Of these substitutions the 25th residue was contained in the casein phosphopeptide (CPP) region. In rats, calcium solubilizing effect of the CPP of bovine variant H was increased by ≈ 23% compared with that of the CPP of non‐H. Using extensive Korean Bos taurus pedigrees, we confirmed that β‐CN H was controlled by a codominant allele.