Molecular weight amino acids

Human PTH consists of a single polypeptide chain of 84 amino acids (molecular weight -9500). Biological activity is associated with the N-terminal portion and residues 1-27 are required for optimal binding and activation of the PTH receptor. PTH (1-84) has a tj in plasma of 2—5 minutes and is predominantly (-90%) cleared by the liver and kidney. 

Symbol Three-letter symbol for the standard amino acids Molecular weight... 

The thioredoxins are small, heat-stable proteins the E. coli thioredoxin has been purified to homogeneity and its complete pr.mary structure has been determined 12). Reduced thioredoxin is a single polypeptide chain of 108 amino acids (molecular weight 11,657) and contains two tryptophan and two cysteine residues. The N-terminal and the C-terminal amino acids are serine and alanine, respectively the amino acid sequence in the vicinity of the cysteines is as follows ... 

The main components of the casein fraction in bovine milk are 0(5-caseins. Bovine milk contains phosphoprotein -casein and a52 Casein, both occurring in four genetic variants, identified by the letters A, B, C and D, which differ somewhat in their primary structure. The most common variant is B, which is a polypeptide chain composed of 199 amino acids (molecular weight 23.6 kDa, p/= 4.92-5.35). aj-Caseins comprise from 44 to 55% of the total caseins and ajj-casein comprises approximately 80% of the total aj-caseins. The polypeptide chain contains eight phosphoserine residues located mainly at positions 43-80, which makes this part of the molecule polar. Non-polar side chains of amino adds are located in positions 100-199. ajj-Casein forms insoluble calcium salts in the presence of calcium ions. Fragments of aji-casein are considered to be. X-casein. a52-Casein has a similar structure (molecular weight 25.2 kDa), but is less sensitive to the presence of calcium ions. 

Amino acid Molecular weight Mass(g) Volume (mL)... 

Enzymes and their sources Number of amino acids Molecular weight of subunit... 

The chemical character of dissolved humic substances in estuaries also reflects its mixed origin, with a number of parameters exhibiting values intermediate between the riverine and oceanic endmembers. These properties include UV-visible absorptivities, C/N ratios, total acidity, molecular weight (Preston, 1979), amino acid content (Fox, 1981), and perhaps C/ C... 

Modern methods of amino-acid and peptide analysis, have enabled the complete amino-acid sequence of a number of proteins to be worked out. The grosser structure can be determined by X-ray diffraction procedures. Proteins have molecular weights ranging from about 6 000 000 to 5 000 (although the dividing line between a protein and a peptide is ill defined). Edible proteins can be produced from petroleum and nutrients under fermentation. 

If the molecular weight of the aniline is known, the number of amino groups can be calculated alternatively, if the aniline is known to be a monacidic base, its molecular weight can be calculated. If the molecular weight and the acidity of the aniline are both known, then dearly the method can be used to estimate the amount of aniline in a given sample. The method is general for many primary and secondary amines, aniline being used solely as a typical member of the former class. 

The calculation depends simply on the fact that 1000 ml. M.NaOH 1 g. mol. of glycine. The method can clearly be used either to deter mine the molecular weight of an amino-acid of known basicity, or to estimate an amino-acid of known molecular weight. 

Dowex 50W-X4 1.1 0.80 Strongly acidic cation exchanger with S-DVB matrix for separation of amino acids, nucleosides and cations. Molecular weight exclusion is < 1400. 

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