Phosvitins

The phosphoprotein phosvitin may attach a large number of ferric ions/mole, according to Gray (99) [citing work of Saltman and Multani], the number bound may be as large as 46. Ferric ion, although firmly complexed, may be removed from this egg yolk protein by dialysis against solutions of ethylenediamine tetraacetic acid (102). 

Phosphoproteins.—A chemical synthesis of partially and fully phosphorylated protamines has been described during the past year,98 and structural requirements for the enzymatic phosphorylation of phosvitin have been delineated.99 Phosphorylated forms of phosphofructokinase100 and fatty acid synthetase101 have been discovered recently both may be concerned with the regulation of their respective enzymes. 

Fig. 6 Evaluation of phosvitin binding to monoclonal anti-phosphoserine antibody by ACE using mobility-shift analysis and UV detection. Peaks M, internal peptide marker mAb, free monoclonal anti-phosphoserine antibody mAb-hpAg complex, monoclonal anti-phosphoserine antibody complexed with homopolyvalent phosvitin antigen. The buffer contained phosvitin within a concentration from 0 to 60 /xM. (Reprinted with permission from Ref. 27. Copyright 1997 Academic Press.)... 

Dickinson, E., Hunt, J.A., Horne, D.S. (1992). Calcium induced flocculation of emulsions containing adsorbed p-casein or phosvitin. FoodHydrocolloids, 6, 359-370. 

Squalene, squalane Phosvitin Phytic acid Phospholipids Spermidine Hyaluronic acid Sphingomyelin Biopolymer Fibronectin Spermine-bile acids Deacylated saponin a-Hemolysin... 

Phosvitin-galactomannan conjugate Pyridoxal phosphate or derivatives Recombinant fusion streptavidin-Mab protein... 

Additional information <1> (<1> isozyme of calmodulin-dependent multifunctional protein kinase II in smooth-muscle [5] <1> caldesmon is not a substrate of smooth-muscle myosin light-chain kinase [3] <1> no substrates are bovine cardiac C-protein, bovine brain fodrin, rabbit skeletal muscle glycogen synthase, phosphorylase B, troponon (I -I- T -I- C), actin, tropomyosin, smooth-muscle actin, filamin, vinculin, cr-actinin, protamine or phosvitin [1]) [1-3]... 

S ATP -I- [DNA-directed eukaryotic RNA polymerase II subunit Ila] (<4> distinct from other protein phosphokinases, transfers about 20 phosphates to the heptapeptide repeats Pro-Thr-Ser-Pro-Ser-Tyr-Ser in C-terminal domain of MW 220000 subunit of RNA-polymerase II [7] <4> substrates are RNA-polymerase II subunits of wheat germ, soy bean, pea and human [7] phosphorylates predominantly Ser-residues [1-3,5,7] <1> kinase CTDKl almost exclusively phosphorylates Ser-residues [5] <1> kinase CTDK2 phosphorylates to a lesser extent Thr-resi-dues [1] <3-5> phosphorylates to a lesser extent Thr-residues [1,5,7] <1> phosphorylates Ser- and Thr-residues equally [6] <1,3,5> phosphorylates not Tyr-residues [1,6] <1> kinase CTDKl 33 mol phosphate per mol IIA-subunit [5] <1> kinase CTDK2 40-50 mol phosphate per mol IIA-subunit, i.e. 1 phosphate per heptapeptide repeat [5] <4> no substrate is GTP [7] <2,4> no substrates are CTP and UTP [3,7] <2> no substrates are dTTP and AMP-PNP [3] <4> no substrates are bovine serum albumin and calf thymus histone [7] <5> no substrate is phosvitin... 

The 216-residue hen egg yolk storage protein phosvitin contains 123 serine residues, most of which have been phosphorylated (Eq. 2-16).295 A basic protein of the myelin sheath of neurons contains as many as 6 specific residues of citrulline (Eq. 2-19).296 An adhesive protein from the foot of a marine mollusk contains -80 repeated sequences containing hydroxy-proline 2,3-dihydroxyproline and 3,4-dihydroxyphenylalanine (Dopa) 297/298... 

Phosphorus-containing macrocycles, 990, 996, 998 macrocychc effect, 1002 ring size, 1003 stereochemistry, 1003 Phosphorus heterocycles transition metal complexes, 1041 Phosphorus ligands, 989-1061 ir-acid series, 1033 bonding, 1030-1041 cone angle concept, 1012 trigonal bipyramidal complexes, 1036 Phosphorus oxychloride metal complexes, 500 Phosphorus ylides transition metal complexes, 1056 Phosphorylation biological, 978 Phosvitin, 975 Photochromism... 

Phosvitin is a highly phosphorylated, iron-containing protein found in egg yolk and serves as an important source of dietary iron.1138 It could be viewed as a source of phosphate, as the protein contains about 130 residues of phosphoserine which appear to serve as ligand groups for iron. 

Isolated phosvitin usually has two to three atoms of iron, with Fe/phosphate ratio about 1 50. Considerably larger amounts of Ca2+ and Mg2+ are bound [(Ca2+ + Mg2+)/phosphate =0.7]. It appears to have no known enzymatic or regulatory role. 

Interaction of cytochrome-c and phophoprotein phosvitin-Formation of a complex with an intact 695-mmu band, Taborsky, G. Biochemistry 1970, 9, 3768. 

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