Important Proteins

Soybean meal is the most frequently used source of supplemental protein in the United States (5). Cottonseed meal is another important protein supplement. Both meals are by-products from oil extraction of the seeds. Canola meal is derived from rapeseed low in emcic acid [112-86-7] and glucosinolates. Linseed (derived from flax seed), peanut, sunflower, safflower, sesame, coconut, and palm kernel meals are other sources of supplemental protein that are by-products of oil extraction (4). 

The globin fold has been used to study evolutionary constraints for maintaining structure and function. Evolutionary divergence is primarily constrained by conservation of the hydrophobicity of buried residues. In contrast, neither conserved sequence nor size-compensatory mutations in the hydrophobic core are important. Proteins adapt to mutations in buried residues by small changes of overall structure that in the globins involve movements of entire helices relative to each other. 

Also, the outcome covers a large spectrum. Autoantibodies can specifically block an important protein (such as the gastric intrinsic factor required for the uptake of orally taken vitamin B12), or the receptor for —> acetylcholine (as in myasthenia gravis), but also can... 

Heme (C34H3204N4Fe) represents an iron-porphyrin complex that has a protoporphyrin nucleus. Many important proteins contain heme as a prosthetic group. Hemoglobin is the quantitatively most important hemoprotein. Others are cytochromes (present in the mitochondria and the endoplasmic reticulum), catalase and peroxidase (that react with hydrogen peroxide), soluble guanylyl cyclase (that converts guanosine triphosphate, GTP, to the signaling molecule 3, 5 -cyclic GMP) and NO synthases. 

Another important protein of the Clp family is ClpB which possesses ATPase activity. In a clpB mutation, 45% of the denatured and aggregated protein arising transiently after the transfer of an E. coli culture from 30 to 45 °C is stabilized [14]. ClpB seems to play an important role in the renaturation or proteolysis of the aggregated proteins, but the mechanism of action of ClpB is not yet known. One can suppose that it might participate in the resolubilization of aggregated proteins. 

Table 49-2. Some other important proteins of muscle.

The next section contains the most relevant findings from ONIOM applications to enzymatic systems performed in our group. This is followed by a discussion of the important protein effects and how this information can be used to improve the modeling of enzymatic reactions. 

Sletta, H., Aune, R., Nedal, A. etal. (2007) The presence of N-terminal secretion signal sequences leads to strong stimulation of the total expression levels of three tested medically important proteins during high-cell-density cultivations of Pichia pastoris. Applied and Environmental Microbiology, 73 (3), 906-912. 

Soybean meal is used worldwide in conventional pig production, as the most important protein source. In addition, there are high value proteins from the... 

The determination of quantity in complex mixtures is also vital in health care and medicine. We are all familiar with the medical examinations in which a sample of blood or urine is sent to a laboratory for analysis. The procedures used have been developed by chemists, and are performed by trained chemical technicians. The high level of automation achieved by the chemists who designed these analytical procedures has greatly reduced the costs of such analyses. Clinical analysis continues to be driven by a need for better methods to detect and measure important proteins, for example, that while present in tiny amounts are relevant to our health and well-being. 

Recombinant DNA technology has had a fourfold positive impact upon the production of pharmaceutically important proteins ... 

Using the same logic, the PTO has granted patents, for example, for pure cultures of specific microorganisms and for medically important proteins (e.g. Factor VIII purified from blood (Chapter 12) and EPO purified from urine (Chapter 10)). 

For a complete functional study of a biological pathway, it is often necessary to confirm the important protein interactions by in vivo experiments. This can be done by demonstrating protein localizations on a microscopic level, for instance, by tagging proteins with the green fluorescent protein or localizing them with antibodies and colloidal gold particles using an electron microscope. Additional, very specific biochemical experiments are often required to confirm the putative protein function. 

Recently, there has been an explosion in our understanding about the nudeocytoplasmic transport systems that import proteins into the nucleus and export them from there. The emerging picture is more complex than expected, maybe too complicated to directly apply this knowledge to the interpretation of localization signals at this time. This section briefly describes the total picture and then summarizes the various signals involved. As there are so many references on this subject, most of the original references were not cited. 

Claros, M., and Vincens, P. (1996). Computational method to predict mitochondrially imported proteins and their targeting sequences. Eur. J. Biochem. 241, 779-786. 

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