Ideal protein

The selected antibody fragments have been used in many applications, varying from antibody-based biochemical assays to in vivo imaging of tumours. The relative ease with which they form multimers and fusion proteins, and the possibility of high levels of expression of these molecules in a variety of different hosts, makes them ideal protein-based diagnostic and possibly future therapeutic reagents (reviewed by Hudson and Kortt) [43] (Figure 10.4). 

As such it is an ideal protein for complementation of legumes. Villegas et al. (73) pointed out that methionine supplementation using sesame protein has several advantages over supplementation with free methionine, including an even and more adequate release into the digestive tract. 

There are several requirements for an "ideal protein system for such studies [68-70]. First, in order to facilitate structure vs. function comparisons, the proteins studied should be of known structure. This structure may be obtained, for example, by high-resolution X-ray spectroscopy. Second, physiological redox protein couples are preferred, since such systems are more likely to provide information on biological design than studies of non-physiological redox couples. Third, for practical purposes, it is... 

The estimates of requirement are based on the assumption that the profile of dietary bioavailable EAA should remain relatively constant during all growth stages, and that a slightly different profile is more appropriate for egg production. The desirable profile has been called ideal protein (IP). The CP need is minimized as the dietary EAA pattern approaches that of IP. The nearer the EAA composition of the diet is to IP, the more efficiently the diet is utilized and the lower the level of N excretion. Energy is also used most efficiently at this point thus, both protein and energy utilization are maximized. 

Firman, J.D. and Boling, S.D. (1998) Ideal protein in Turkeys. Poultry Science 77, 105-110. 

Measurements of the levels of semm proteins such as albumin, transthyretin (also known as prealbumin), transferrin and retinol-binding protein are used as biochemical parameters in the assessment of protein energy malnutrition (Table 17-1). An ideal protein marker should have rapid turnover and present in sufficiently high concentrations in semm to be measured accurately. Transthyretin has these properties it is a sensitive indicator of protein deficiency and is effective in assessing improvement with refeeding. 

The properties of proteins that promote emulsion formation are also important in the creation of foams. Poole and Fry [44] suggested that the ideal protein for foaming would posses high surface hydro-phobicity, high solubility, and a low net charge at the pH of the food product. To exhibit functional performance, the protein must reach the air/water interface. Rapid diffusion and unfolding at the interface is required to lower the interfacial tension between the air and the water phase [45]. Factors that increase the rate of protein diffusion have also been reported to enhance protein foaming [46,16]. 

Figure 9.2.10 summarizes the approximate geometrical shapes of proteins for hypothetical ideal proteins made of 300 amino acids. The longest structures are always helical. Sheet or globule formation as well as coiling leads to much shorter extensions. 

Here is an easy way to approximate your ideal protein serving. Look at the palm of your hand—not the fingers, just your palm. At each meal, your ideal protein serving should be roughly the same size, whether you re talking about chicken, beef, seafood, or tofu. For most women, that would be roughly three or four ounces, while for most men the serving size is about five or six ounces. 

Based on a protein requirement of 12% plus an ideal protein (100% true digestibility and 100% biological value). 

Melittin is an ideal protein to illustrate the effects of structure on the fluorescence spectral properties. Each monomer contains a singly tryptophan residue and no tyrosine residues. The X-ray structure of the tetrameric form shows that the tryptophan residues are buried in a non-polar pocket and are not directly exposed to the aqueous phase. 

Urry,D.W., Hugel,T., Seitz, M. etal. (2002) Elastin a representative ideal protein elastomer, i /t/toioplt/ca/ Transactions of the Royal Society B Biological Sciences, 357, 169-184. 

D.W. Urry,T. Hugel, M. Seitz, H. Gaub, L. Sheiba, J. Dea, J. Xu, L. Hayes, F. Prochazka, and T. Parker, Ideal Protein Elasticity The Elastin Model. In Elastomeric Proteins Structures, Biomechanical Properties and Biological Roles P.R. Shewry, A.S. Tatham, and A.J. Bailey, Eds. Cambridge University Press, The Royal Society Chapter Four, pages 54-93,2003. 

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