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    Heat-set gelation of milk- and fermentation-derived β-lactoglobulin variants
    (Elsevier Ltd, 2025-08) Pan Z; Kornet R; Hewitt S; Welman A; Hill JP; Wubbolts M; Mitchell S; McNabb WC; Ye A; Acevedo-Fani A; Anema SG
    Milk-derived β-lactoglobulin (mβ-LG) and fermentation-derived β-lactoglobulin (fβ-LG) may slightly differ in their amino acid sequences. This study aims to investigate the heat-set gelling behaviour of mβ-LG (variants A, B, and C) and fβ-LG A variants. Differential scanning calorimetry indicated similar denaturation temperatures for mβ-LG A and fβ-LG A (∼75 °C), with mβ-LG C highest (∼81 °C) and mβ-LG B intermediate (∼78 °C). All fβ-LG A formed translucent gels with a fine-stranded structure, whereas mβ-LG A, B, and C formed opaque gels with a coarse particulate structure. fβ-LG A exhibited delayed gelation onset and lower gel stiffness compared to mβ-LG A. Among mβ-LG's, mβ-LG A showed the highest gel stiffness, followed by mβ-LG B and then mβ-LG C. Rheological analysis showed that fβ-LG A gels were more elastic and ductile compared to mβ-LG A gels, indicated by smaller tan δ values and delayed increases in energy dissipation ratio at higher strain amplitude; mβ-LG B and mβ-LG C gels were less elastic but more ductile compared to mβ-LG A gels. The more elastic and ductile nature of fβ-LG A gels indicates their potential for applications requiring these specific textural properties. By selecting mβ-LG variants from milk and/or utilizing precision fermentation to engineer additional differences, it is possible to tailor the gelation characteristics of β-LG to meet specific functional requirements.
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    The amino acid sequence of the tryptic peptides of the f1 bacteriophage coat protein : a thesis submitted to Massey University of the Manawatu in partial fulfilment of the requirements for the degree of Master of Science in Biochemistry
    (Massey University, 1970) Richardson, Barry Charles
    Five major peptides were isolated by paper electrophoresis from a tryptic digestion of purified fl bacteriophage coat protein. The amino acid composition of the peptides was determined and shown to be:- T1 Ala2, Glu1, Asp2, Pro1, G1yl, Lys1. T2 Al1, Ser1.T3 Phe1, Thr1, Ser1, Lys1. T4 Leu1, Phe1, Lys1. T5 Lys1. Sequential degradation of the intact fl coat protein using the Edman technique showed the N-terminal sequence to be:- Ala - Glu - Gly - Asp - Asp - T1:- The sequence of the tryptic peptide T1 indicated it was derived from the N-terminal of the protein and was assigned the sequence:- Ala - Glu - Gly - Asp - Asp - (Pro1,Ala1) - Lys. T2:- After two cycles of the Edman degradation reaction the sequence of T2 was shown to be:- Ala - Ser Digestion of the intact f1 coat protein with carboxypeptidase A indicated T2 was the C-terminal peptide since carboxypeptidase A showed the C-terminal sequence to be:- - Lys - Ala - Ser T3:- Thin peptide was shown to have the sequence:- Phe - Thr - Ser - Lys T4:- This peptide was assigned the sequence Leu - Phe - Lys T5:- T5was shown be a free Lys residue.