Amino acid research

J. Woods, C. France, J. Hartman, S. Baron, and J. Cook in E. Cavalheiro, J. Lehman, and L. Turski, Eds., Excitatory Amino Acid Research, Alan Liss, New York, 1988, pp. 317-323. 

Watkins JC (1986) Twenty-five years of excitatory amino acid research. The end of the beginning In Roberts PJ, Storm-Mathisen J, Bradford HF (Eds), Excitatory Amino Acids. London Macmillan, pp 1-39. 

With the introduction of a further carbon atom between the amino and carboxy groups, we pass from (3- to y-amino acids. Research on y-amino acids and on the preparation of y-peptides is still in its infancy, but will undoubtedly increase during the next few years, as these unnatural peptides have already been shown to have interesting structural features, for example the tendency to adopt new stable helical structures [106,107],... 

With improvements in analytical techniques for the analysis of sugars in seawater, it is likely that our concepts of the distribution of individual compounds will change analogous to the developments in amino-acid research. 

The seeds of legumes and cereal grains provide humans with an estimated 70 percent of their dietary protein requirements, but the proteins in these seeds are also deficient in certain essential amino acids. Researchers have examined the possibility of genetically engineering the genes that code for these proteins to alter their amino acid composition, but they are complex, multigene families. 

Amino Acids publishes contributions from all fields of amino acid research analysis, separation, synthesis, biosynthesis, cross linking amino acids, race-mization/enantiomers, modification of amino acids as phosphorylation, methylation, acetylation, glycosylation and nonenzymatic glycosylation, new roles for amino acids in physiology and pathophysiology, biology, amino acid analogues and derivatives, polyamines, radiated amino acids, peptides, stable isotopes and isotopes of amino acids. 

Cancer Research, Osaka University Medical School, for his useful advice and encouragement. The early part of this work was carried out in Prof. Sakamoto s laboratory. This study was supported in part by a grant from the Scientific Research fund of Ministry of Education and Culture of Japan, from TANABE Amino Acid Research Fund and from KANAE Shinyaku Kenkyu-Kai Fund. 

Supported by Ajinomoto Amino Acid Research Program, NIH ROl AR-44474, and USDA/ARS... 

Ottersen OP, Bramham CR (1988) Quantitative electron microscopic immunocytochemistry of excitatory amino acids. In Cavalheiro EA, Lehmann J, Turski L (eds) Frontiers in excitatory amino acids research. Alan R Liss, New York, pp 93-100... 

Each element of matrix corresponds to the probability that the amino acid in coiumn wiii mutate to the jmino acid in row j after a period of 1 PAM. The vaiues have been multipiied by 10000. (Based on Dayhoff M O 1978. Atlas of Protein Sequence and Structure Voiume 5 Suppiement 3. Dayhoff M O (Editor) Georgetown Jniversity Medicai Center, National Biomedical Research Foundation Figure 82.)... 

T. E. Stewart, M Survey of the Chemistry of Amino Acids-Reducing Sugar Reaction in Relation to Aroma Production, Scientific and Technical Surveys No. 61, British Eood Manufacturing Industries Research Association, London, Dec. 1969. 

P-Endorphin. A peptide corresponding to the 31 C-terminal amino acids of P-LPH was first discovered in camel pituitary tissue (10). This substance is P-endorphin, which exerts a potent analgesic effect by binding to cell surface receptors in the central nervous system. The sequence of P-endorphin is well conserved across species for the first 25 N-terminal amino acids. Opiates derived from plant sources, eg, heroin, morphine, opium, etc, exert their actions by interacting with the P-endorphin receptor. On a molar basis, this peptide has approximately five times the potency of morphine. Both P-endorphin and ACTH ate cosecreted from the pituitary gland. Whereas the physiologic importance of P-endorphin release into the systemic circulation is not certain, this molecule clearly has been shown to be an important neurotransmitter within the central nervous system. Endorphin has been invaluable as a research tool, but has not been clinically useful due to the avadabihty of plant-derived opiates. 

Point Mutations. Since the advent of recombinant DNA technology, a number of researchers have used point mutation techniques either to delete one or more residues within the hGH molecule or systematically to change from one amino acid to another to probe hGH stmcture/function relationships (33). 

Asymmetric synthesis is a method for direct synthesis of optically active amino acids and finding efficient catalysts is a great target for researchers. Many exceUent reviews have been pubHshed (72). Asymmetric syntheses are classified as either enantioselective or diastereoselective reactions. Asymmetric hydrogenation has been appHed for practical manufacturing of l-DOPA and t-phenylalanine, but conventional methods have not been exceeded because of the short life of catalysts. An example of an enantio selective reaction, asymmetric hydrogenation of a-acetamidoacryHc acid derivatives, eg, Z-2-acetamidocinnamic acid [55065-02-6] (6), is shown below and in Table 4 (73). 

Feeding standards, which have been instituted nationally, indicate the amount of the essential amino acids (together with other nutrients) for the rational breeding of domestic animals. The feeding standards of the National Research Council (NRC) of the United States and Agricultural Research Council (ARC) of the United Kingdom are well known (the former indicates the minimal amount and the latter shows the recommended amount). 

To date, the most extensively studied polyboron hydride compounds in BNCT research have been the icosahedral mercaptoborane derivatives Na2[B22H22SH] and Na [(B22H22S)2], which have been used in human trials with some, albeit limited, success. New generations of tumor-localizing boronated compounds are being developed. The dose-selectivity problem of BNCT has been approached using boron hydride compounds in combination with a variety of deUvery vehicles including boronated polyclonal and monoclonal antibodies, porphyrins, amino acids, nucleotides, carbohydrates, and hposomes. Boron neutron capture therapy has been the subject of recent reviews (254). 

Soybean Protein Isolates. Soybean protein isolates, having a protein content of >90 wt%, are the only vegetable proteins that are widely used in imitation dairy products (1). Most isolates are derived from isoelectric precipitation, so that the soybean protein isolates have properties that are similar to those of casein. They are insoluble at thek isoelectric point, have a relatively high proportion of hydrophobic amino acid residues, and are calcium-sensitive. They differ from casein in that they are heat-denaturable and thus heat-labile. The proteins have relatively good nutritional properties and have been increasingly used as a principal source of protein. A main deterrent to use has been the beany flavor associated with the product. Use is expected to increase in part because of lower cost as compared to caseinates. There has been much research to develop improved soybean protein isolates. 

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