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CHARACTERIZATION OF CAMEL MILK B-CASEIN

Muhammad, Ashiq (1993) CHARACTERIZATION OF CAMEL MILK B-CASEIN. PhD thesis, University of Karachi, Karachi.

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Abstract

Present study was undertaken to characterize camel milk caseins. The major objective was to isolate, purify and elucidate the structure of caseins (known classes of proteins as well as unidentified proteins) Primary structure of β-casein has been investigated along with partial characterization of novel N-terminally blocked casein β-casein was purified by ion exchange chromatography and its structure was determined by analysis of intact protein and peptides generated by enzymatic cleavage I.e. Lys-C, Arg specific and Asp-N by manual (DABITC) as well as on gas phase sequence. Camel milk β-casein contains 217 amino acid residues with molecular mass of 28600 dalton (on the absis 64%, 63% 48%, 62% homology. Camel β-casein shows 40% conservation to afore mentioned β-casein. It shows an extension of 7 residues at its C-terminal when compared to bovine, ovine and buffalo β-casein. It has a number of short tandem repeats. Primary structure of β-casein shows several biologically active peptides i.e. β-casomorphin, angiotensin-1 converting enzyme inhibitor, immunostimulating peptides and a large number of opioid peptides Partial characterization of a novel casein has been achieved from acid precipitated camel milk casein. It was purified by reversed phase HPLC. It has molecular mass of 25 kDa as determined of SDS-PAGE. Sequence studies revealed that it was N-terminally blocked. The amino acid analysis differs from known classes of casein i.e. as1, as2, β and k-casein. It’s distinct nature stdnds out due to the absence of praline and methionine, which has been found in caseins characterized till date

Item Type:Thesis (PhD)
Uncontrolled Keywords:camel milk, casein, proteins, peptides, amino acid, camelus dromedaries
Subjects:Physical Sciences (f) > Chemistry(f2)
ID Code:1220
Deposited By:Mr. Muhammad Asif
Deposited On:04 Jan 2007
Last Modified:04 Oct 2007 21:05

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