Proteins compounds with carbohydrates

Peptides and proteins form a wide range of conjugated compounds with carbohydrates. Carbohydrates are present mostly as linear or branched oligosaccharides. In some conjugated compounds the properties of peptide (protein) predominate, therefore these complex saccharides include ... 

Glycoproteins or mucoproieins. Compounds of proteins with carbohydrates. All glycoproteins contain a hexosamine and usually sulphate, ethanoate and glucuronic acid. The carbohydrate-protein linkages are, in some cases covalent and in others of the salt type. Aqueous solutions of glycoproteins are extremely viscous. 

As a rule of thumb, one can say that the efficiency of separation of mixtures and the simplicity of operating and maintaining apparatus are much greater for GC than for LC. Hence, other things being equal, GC is most often the technique of first choice and can be used with a very wide variety of compound types. However, for nonvolatile or thermally labile substances like peptides, proteins, nucleotides, sugars, carbohydrates, and many organometallics, GC may be ruled out completely... 

Mucoproteins (See Section V).—Protein-carbohydrate compounds with relatively high protein or peptide content, the chemical reactions of which are predominantly protein, are known as mucoproteins. In general they do not coagulate on being heated in aqueous solution. All mucoproteins contain a hexosamine constituent. 

The results obtained with this procedure are similar to those previously reported in the literature by Hangartner, Hagenguth et al and Zeman et al (4, 2, 5, 6). The major exception, being the complete lack of alkylated pyrazines and alkylated thiophenes. These odour-intensive compounds arise from the thermal decomposition of proteins and sulphur containing amino acids. They also develop in the thermally induced reaction of proteins with carbohydrates (Maillard reaction). The authors indicated above have demonstrated that these compounds are invariably produced during the thermal treatment of sludge, a process which is not used in this Authority. 

NUCLEOPROTEINS AND NUCLEIC ACIDS. Nucleic adds are compounds in which phosphoric acid is combined with carbohydrates and with bases derived from purine and pyrimidine. Nucleoproteins are conjugated proteins consisting of a protein moiety and a nucleic acid. Originally, nucleoproteins were thought to occur only in the nuclei of cells, but it was later established that they are far more widely distributed, being found in cells of all types, animal and plant. They are found in the chromosomes, in the genes, in viruses, and bacteriophages. 

The convention has over the last three decades proved to be adaptable, versatile and universal.9 It should be pointed out, however, that with amino acids (Section 5.14.4, p. 746), and hence in peptide and protein chemistry, and with carbohydrates (Section 5.10), the d/l convention is still the more convenient, mainly because it is used specifically to designate generic relationships between an enormous number of compounds of closely related structure. 

The plots of the intensities of selected characteristic bands as a function of lateral position (so-called chemical maps) provide information on the amount of the respective molecules or molecular groups in the different morphological structures (Fig. 4.2). The band at 784 cm 1 can be assigned to out-of-plane deformation vibrational modes of the nucleobases cytosine, thymine and uracil and serves as an indicator for the presence of nucleic acids. At 483 cm-1, a C-C-C deformation of carbohydrate polymers such as starch or pectin is present in some of the spectra. To study the distribution of protein compounds, we analysed characteristic signals of the amino acid phenylalanine (1002 cm 1 ring breathe) as well as of the protein amide I band (1651 cm-1) that is brought about by vibrations of the protein backbones. The maximum of the phenylalanine signal co-localizes with a maximum in protein content... 

Phosphorus is found in every cell of the body, but most of it (about 80% of the total) is combined with calcium as Ca3(P04)2 in the bones and teeth (Harper 1969 Tietz 1970). Phosphorus is present in cells mainly as organic phosphate, with a small amount in serum as inorganic phosphate (Tietz 1970). Phosphorus is involved in the intermediary metabolism of carbohydrates (Tietz 1970). About 10% is found in combination with proteins, phospholipids, and carbohydrates and in other compounds in the blood and muscle (Harper 1969). The remaining phosphorus is widely distributed in various chemical compounds such as nucleic acids, nucleotides, and adenosine triphosphate (ATP) (Tietz 1970). 

The reactive electrophilic acyl and carbonyl compounds produced by oxidative dehalogenation may react with nucleophilic biological molecules such as DNA, proteins, lipids and carbohydrates to possibly form toxic metabolites. 

In the microarray industry, the most commonly used techniques to pattern biologically active molecules are robotic contact printing or ink-jet printing. In general, these methods can fabricate biochips with thousands of different compounds, which can be analyzed simultaneously. The most commonly spotted biomolecules include oligonucleotides,1 proteins,2 and carbohydrates.3 Microarray-based platforms have... 

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