The effect of casein genetic variants, glycosylation and phosphorylation on bovine milk protein structure, technological properties, nutrition and product manufacture

Probing of alpha, beta and kappa-caseins polymorphic variants in Gangatiri cow milk with the use of polyacrylamide gel electrophoresis and HRAMS

“…The genetic polymorphisms that cause nine protein variations of αS1-Cn coded by the CSN1S1 gene in cattle have been identified and categorized from A to I (Nadugala et al ., 2022). The variants B and C are the two most prevalent variations, which differ in the exchange of glutamic acid positioned at 192 with glycine amino acid in mature proteins.…”

The role of glycosylation in amyloid fibril formation of bovine κ-casein

“…The rennet cleavage site is located between the 105 and 106 amino acid residues. Full amino acid sequence and amino acid sequence of other κ-CN genetic variants can be found in Hewa Nadugala et al (2022) . Numbers represent the amino acid residue position in the sequence.…”

“…The TEM micrographs show that both UG and 2G κ-CN B are present as curly and rugged surface linear aggregates, which aligns with Chun et al (2012) who observed thicker fibrils with a rugged surface using unreduced forms of κ-CN, while Ecroyd et al (2008) , Ecroyd et al (2010) , Leonil et al (2008) , and Pan and Zhong (2015) observed substantially longer fibrils with a smooth surface using reduced forms of κ-CN. Although disulphide bond reduction does not significantly affect the secondary and tertiary structure of κ-CN ( Farrell et al, 2003 ), it is believed that the ability of κ-CN to form oligomers, and the subsequent propensity for amyloid fibril formation, is influenced by changes in the number of disulphide bonds links of cysteine 11 and cysteine 88 ( Hewa Nadugala et al, 2022 ; Rasmussen et al, 1992 ). This indicates that β-sheet assembly might be different with the presence or absence of disulphide bonds during fibril formation.…”

“…κ-CN is 169 amino acids in length, containing one tryptophan residue and belongs to the intrinsically disordered protein family that lacks an ordered tertiary structure ( Farrell et al, 2004 ; Farrell et al, 2003 ). There are 14 κ-CN genetic variants that have been identified so far and the amino acid sequence for the κ-CN variants reported herein are described in Hewa Nadugala et al (2022) . The κ-CN A and B variants are the predominant genetic variants of dairy cattle.…”

Partitioning of casein and fat in Cheddar cheese manufacturing as affected by cheese milk standardisation: A review

“…Higher concentration of κ-casein and casein/ total protein in milk appeared to be responsible for improved whey drainage, lower total protein content in whey, higher fat and FDM in cheese as well as reduced casein, solids and nitrogen partitioning in whey (Hallén et al 2010;Amalfitano et al 2019;Reale et al 2020). This was attributed to a tighter casein network due to presence of smaller casein micelles in milks with higher κ-casein levels (Nadugala et al 2022). The dependence of curd strength on micellar size has been reported (Glantz et al 2010), and smaller micelles that are associated with better gelation properties and curd strength were associated with κ-casein BB, β-casein BB and αS1-casein BC variants (Nadugala et al 2022;Kruchinin et al 2023).…”