Red protein

Red blood cells—Type of blood cell filled with the red protein hemoglobin that carries oxygen to tissues. 

DFR belongs to the single-domain-reductase/epimerase/dehydrogenase (RED) protein family, which has also been termed the short chain dehydrogenase/reductase (SDR) superfamily. This contains other flavonoid biosynthetic enzymes, in particular the anthocyanidin reductase (ANR), leucoanthocyanidin reductase (EAR), isoflavone reductase (IFR), and vestitone reductase (VR), as well as mammalian, bacterial, and other plant enzymes. ... 

Like LAR, ANR is a member of the RED protein family. Full details of the protein structure and reaction mechanism are yet to be published. However, Xie et al. compared the A. thaliana (AtANR) and M. truncatula (MtANR) ANR amino acid sequences and recombinant protein activities, and made suggestions on the possible reaction series. The two recombinant proteins showed significantly different kinetic properties, substrate specificities, and cofactor requirements. Although AtANR and MtANR share only 60% sequence identity, some well-conserved domains are evident, in particular the Rossmann dinucleotidebinding domain (GxxGxxG) near the N-termini. However, two amino acid variations did... 

Gordon, W. G., Groves, M. L. and Basch, J. J. 1963. Bovine milk "red protein" Amino acid composition and comparison with blood transferrin. Biochemistry 2, 817-820. 

Fig. 9.—Structure of Glycans105 of Bovine-milk Lactotransferrin ( Red Protein ).

Recently, another red protein Buchanan, Lovenberg, and Rabinowitz 32) Mortenson 72) has been isolated in crystalline form from C. pasteurianum and certain of its properties determined Lovenberg and Sobel 67)). Lovenberg and Sobel 67) named it rubredoxin because of its color and properties of an electron carrier. They showed rubredoxin differed from ferredoxin in absorption spectrum, composition and redox potential. Rubredoxin contained no inorganic sulfide the recent demonstration 49) of the similarity of the optical rotatory dispersion spectra of rubredoxin and bacterial ferredoxin makes a further comparison of the properties of these proteins particularly interesting. 

Johanson, B. Isolation of an iron-containing red protein from human milk. Acta Chem. Scand. 14, 510 (1960). 

If red blood corpuscles are placed in pure water they swell, become round, and finally burst. This is the result of the fact that the cell wall is permeable to water but nOt to some of the solutes of the cell solution (mainly hemoglobin the red protein in red cells) in the effort to reach a condition of equilibrium (equality of water vapor pressure) between the two liquids water enters the cell. If the cell wall were sufficiently strong, equilibrium would be reached when the hydrostatic pressure in the cell had reached a certain value, at which the water vapor pressure of the solution equals the vapor pressure of the pure w ter outside... 

Lactoferrin was first identified as a red protein fraction in human milk (1). The milk protein has been called by various names of red milk protein, ekkrino-siderophilin, and lactotransferrin which is in turn very similar in many respects to transferrin, the ironbinding protein of serum. The concentration of lactoferrin in human milk is unusally rich with a range of 7 mg/ml in colostrum to approximately 1 mg/ml in mature milk (2). However, the bovine colostrum contains lactoferrin at concentrations of 5 mg/ml, which drops very rapidly with stage of lactation to where mature bovine milk contains 20-200 pg/ml of lactroferrin (3). Lactoferrin is also found in various other exocrine secretions of the body such as vaginal, nasal, bronchial and intestinal (4 6). 

Interaction surfaces of three hydrogen bond acceptors in thrombin (shown in red). Protein atoms are drawn with sticks, ligand atoms with balls. ... 

In the meantime, in 1947, Laurell and Ingelman[17] had independently purified the red protein from pig plasma and in the same year proposed the name transferrin which has since been adopted as the generic name of the proteins of this family serotransferrin (instead of siderophilin) present in blood and some external secretions, ovotransferrin (instead of conalbumin) in avian egg-white, lactotransferrin (also called lactoferrin) from milk, external secretions and leukocytes and melanotransferrin (instead of p97) in melanocyte and normal cell plasma membrane. A dozen mammalian and some frog, fish and insect serotransferrins were later isolated and characterized. 

Cacao Shell, Cocoa shells. Shells ol the seed of Theobroma cacao L., Sterculiaceae. Habit. Brazil, Central America, Mexico, West Indies, and most tropical countries. Constit. Theobromine, caffeine, cacao red. protein, pentosans, pec tic acid, starch. Ref Dittmar, Ettgenharia e quim S, no. ], I (1953), C.A. 48, 2949e (1954). Monographs.- E. M, Chatt, Cocoa (Interscience, New York, 1953) D, H. Urquhart, Cocoa (Longmans, London, I960 Powell, Harris, Chocolate and Cocoa in Kirk-Ot(inter Encyclopedia of Chemical Teh nofogy. vol. 5 (Interscience, New York, 2nd ed., 1964) pp 363-402. 

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