Methionine formula

Sulfoxides occur widely in small concentrations in plant and animal tissues, eg, aHyl vinyl sulfoxide [81898-53-5] in garlic oil and 2,2 -sulfinylbisethanol [3085-45-8] as fatty esters in the adrenal cortex (1,2). Homologous methyl sulfinyl alkyl isothiocyanates, which are represented by the formula CH3SO(CH2) NCS, where n = 3 [37791-20-1], 4 [4478-93-7], 5 [646-23-1], 8 [75272-81-0], 9 [39036-83-4], or 10 [39036-84-5], have been isolated from a number of mustard oils in which they occur as glucosides (3). Two methylsulfinyl amino acids have also been reported methionine sulfoxide [454-41-1] from cockroaches and the sulfoxide of i -methylcysteine, 3-(methylsulfinyl)alaiiine [4740-94-7]. The latter is the dominant sulfur-containing amino acid in turnips and may account in part for their characteristic odor (4). 

Without consulting chapter figures, draw Fischer projection formulas for glycine, aspartate, leucine, isoleucine, methionine, and threonine. 

D-Methionine, systematic name, formula, and molecular weight, 2 556t DL-Methionine... 

Methionine (Met or M) ((5)-2-amino-4-(methylsulfanyl)-butanoic acid) is a nonpolar, neutral, amino acid with the formula HOOCCH(NH2)CH2CH2SCH3. Together with Cys, Met is one of the two sulfur-containing proteinogenic amino acids and a great antioxidant. Its derivative 5-adenosyl methionine (SAM) serves as a methyl donor. ... 

Nutrition may have a considerable effect. A high intake of milk protein in neonates will result in an increase in most plasma amino acids, especially methionine and tyrosine. Canned infant formulae may contain homocitrulline, which may appear in the patient s urine. White meat (chicken ) will contain carnosine, anserine, and... 

Using partial structural formulas, describe the reactions by which serine and methionine react to form N-formy I methionine needed for protein synthesis. 

AA Toran, R Barbera, R Farre, MJ Lagarda, JC Lopez. HPLC Method for cyst(e)ine and methionine in infant formulas. J Food Sci 61 1132-1135, 1996. 

KEY CONCEPT PROBLEM 3.6 Methionine, an amino acid used by organisms to make proteins, can be represented by the following ball-and-stick molecular model. Give the formula for methionine, and calculate its molecular mass (red = O, gray = C, blue = N, yellow = S, ivory = H). 

Modified to avoid the inclusion of groundnut meal, meat-and-bone meal and pure methionine in the original formulas. 

Since D-amino acids are poorly utilized, diets containing sufficient quantities of D-enanticmers will result in elevated levels of plasma and urinary amino acids. Urinary excretion of D-methionine by infants fed a formula supplemented with DD-methionine has led to misdiagnosis of inborn errors of metabolism (77). D-Amino acids derived from processed food proteins may confuse medical diagnoses. Determining D-amino acid contents of caimon foods would estimate the significance of this problem. Some preliminary results are shown in Table VI. 

In general the thiol proteases catalyze the hydrolysis of a variety of peptide, ester, and amide bonds of synthetic substrates. Employing the general formula R —NH—CHR—CO—X, cleavage of the —CO—X— bond has been demonstrated when R represents the side chain of glycine, threonine, methionine, lysine, arginine, citrulline, leucine, and tyrosine. 

Figure 2 Structural analogs of 5,5-AdoMet with replacements in the sulfonium center and the transferable methyl group. Formulas are aligned to show the methyl group (or its equivalent) above, and the C-y and C-5 atoms below to the left and right side from the onium center, respectively, (a) 5-adenosyl-L-methionine (AdoMet) (b) Se-adenosyl-L-selenomethionine (Se-AdoMet) (c) Fe-adenosyl-t-telluromethionine CFe-AdoMet) ...

The structures of higher peptides follow in an analogous fashion. Figure 27.7 gives the structural formula and amino acid sequence of a naturally occurring pentapeptide known as leucine enkephalin. Enkephalins are pentapeptide components of endorphins, polypeptides present in the brain that act as the body s own painkillers. A second substance, known as methionine enkephalin, is also present in endorphins. Methionine enkephalin differs from leucine enkephalin only in having methionine instead of leucine as its C-terminal amino acid. 

The proteins in our bodies are composed of molecules called amino acids. One amino acid is methionine its molecular formula is C5H N02S. Calculate ... 

Figure 7 Allergenic character of products obtained from cow s milk proteins by food processing or enzymatic modifications. (1) Cow s milk (2) Na-caseinate (3) kefir (4) yogurt (5) cheese (6,7,8) a-chymotryptic, tryptic, and peptic hydrolysates of casein, respectively (9,10,11) a-chymotryptic tryptic, and peptic EPM products of casein, respectively (12,13) a-chymotryptic and tryptic EPM products of casein, respectively, with methionine enrichment (14,15) fractions of a-chymotryptic EPM products of casein (16,17) fractions of peptic EPM products of casein (18) commercial hypoallergenic formula.

Two pentapeptides found in the brain are known as enkephalins, namraUy occurring analgesics (pain relievers). For molecules of this size, abbreviations for the amino acids are more convenient than structural formulas. The same notation is used for the amino acid sequence, with the N-terminal amino acid listed first and the G-terminal listed last. The two peptides in question, leucine enkephalin and methionine enkephalin, differ only in their Ckterminal amino acids. 

The methionine-, threonine-, vafine- and isoleucine-free infant formula XMTVl Analog is suitable for the... 

Although it had been stated that D-methionine was utilized by man (91), D-methioninuria as well as fecal methionine sulfoxide were consistently observed when a soy formula containing D,L-methionine was fed to infants (93,94). As a result of these findings, use of D,L-methionine was forbidden in infant formulas based on soy (115). Recently, in a metabolic study (95) using nitrogen balance as a criterion for utilization, D-methionine was... 

However, these compounds do not exhibit complex I inhibition, but are reported to inhibit the biosynthesis of methionine. The pioneers of the complex I-aminoalkylpyrimidine class are chemists from Ube Industries, who were inspired by a publication of Whitehead and Traverse reporting the diuretic properties of some 4-aminopyrimidine derivatives [5]. Aminoarylalkyl-substituted pyrimidine compounds of the general formula II [6] (Fig. 13.5.3) were first patented in 1988, claiming both insecticidal and fungicidal activity like, for example, rice blast, powdery mildew and downey mildew. Interestingly, diflumetorim (4), Ube s development compound was already generically claimed in this first application but not exemplified either in the text or in the respective tables. 

The species H2Ar, HAl", andAl correspond to the forms H2B,HB andB of ordinary dibasic acids of the formula H2B. Certainly, there is also an equilibrium of intramolecular proton transfer, i.e., a tautomeric equilibrium HAl HAl. However, its equilibrium constant is so large that the concentration of HAl is very small. In ethanol-water mixtures as solvent, the respective equilibrium constants of glycine, L-alanine, L-valine, L-leucine, L-phenylalanine, L-isoleucine, L-methionine, and L-serine are aU between 10 and 10 [8]. 

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