Monosaccharides acidic

Stage 2 Fatty acids, monosaccharides, and amino acids are degraded in cells to yield acetyl CoA. 

We are using GC/MS for profiling primary metabolites in M. truncatula. This approach allows for the simultaneous profiling of approximately 300 to 500 components, including amino acids, organic acids, monosaccharides, disaccharides,... 

Place the flask in the water bath without the stopper and add 10.0 mL of concentrated hydrochloric acid to the flask. Heat for 45 min at a gentle boil and shake the flask at 10-min intervals. The HCl-heat combination breaks up the food sample, releasing free fatty acids, monosaccharides, amino acids, etc., thus making extraction easier. 

N-acetylneuraminic acid (sialic acid, 5), is a characteristic component of glycoproteins. Other acidic monosaccharides such as D-glu-curonic add, D-galacturonic add, and liduronic add, are typical constituents of the glycosa-minoglycans found in connective tissue. 

Monosaccharides also form phosphate esters with phosphoric acid. Monosaccharide phosphate esters are important molecules in biological system. For example, in the DNA and RNA nucleotides, phosphate esters of 2-deoxyribose and ribose are present, respectively. Adenosine triphosphate (ATP), the triphosphate ester at C-5 of ribose in adenosine, is found extensively in living systems. 

The lysosomal disorder SASD is characterized by accumulation of the free acid monosaccharide sialic acid in the lysosomal compartment of the cell. Diagnosis is based on the demonstration of abnormal excretion of free, not OGS-bound sialic acid in urine, coupled with accumulation of free sialic acid in cultured fibroblasts, and on microscopic evidence of vacuoles (increased and swollen lysosomes filled with light electron-lucent material in skin biopsy and peripheral blood lymphocytes). The inheritance is autosomal recessive. There are different clinical forms of this disorder an adult form, called Salla disease (SD) or Finnish sialuria (OMIM 604369) infantile SASD (ISSD OMIM 269920) and an intermediate form, severe Salla disease [3,16]. 

Mancini GM, Beerens CE, Aula PP, Verheijen FW (1991) Sialic acid storage diseases. A multiple lysosomal transport defect for acidic monosaccharides. J Clin Invest 87 1329-1335... 

Fig. 4.5.4 Identification of mutations in the transferrin protein by neuraminidase treatment. Unusual patterns in the IEF of serum transferrin might lead to pitfalls in CDG diagnostics. These varying patterns are often due to mutations of charged amino acids in the protein backbone of the transferrin molecule, which might lead, for example, to an accumulation of trisialo transferrin bands (lane 3, indicated by a question mark). Further investigations are carried out by cleaving off charged sialic acid monosaccharide moieties from transferrin-linked oligosaccharides by neuraminidase treatment, followed by IEF and transferrin antibody staining. In the case of protein mutations, additional bands below (lane 4) or above (not shown) the desialylated transferrin form appear...

Structural elucidation of natural macromolecules is an important step in understanding the relationships between the chemical properties of a biomolecule and its biological function. The techniques used in organic structure determination (NMR, IR, UV, and MS) are quite useful when applied to biomolecules, but the unique nature of natural molecules also requires the application of specialized chemical techniques. Proteins, polysaccharides, and nucleic acids are polymeric materials, each composed of hundreds or sometimes thousands of monomeric units (amino acids, monosaccharides, and nucleotides, respectively). But there is only a limited number of these types of units from which the biomolecules are synthesized. For example, only 20 different amino acids are found in proteins but these different amino acids may appear several times in the same protein molecule. Therefore, the structure of... 

Plant cell wall polysaccharides are composed of varying proportions of the neutral monosaccharides rhamnose, fucose, arabinose, xylose, mannose, galactose, and glucose, and the acidic monosaccharides galacturonic acid, glucuronic acid, and 4-0-methylgIucuronic acid (see Fig. E3.2.1). Other monosaccharides have been identified but are present only in trace... 

Table 15.10 presents a summary of the applications of gas chromatography to the determinations of other organic compounds, including chlorofluoroparalfins, carboxylic acids, monosaccharides, organosulphur compounds, polychlorobiphenols and azine herbicides in seawater. 

Figure 8.21 Porewater size/reactivity model (PWSR) model used to describe the cycling of DOM in sediments. Similar to remineralization of POM described earlier for the water column, sedimentary POM is initially hydrolyzed by bacteria in the benthos to HMW DOM this is further hydrolyzed to monomeric LMW DOM (mLMW DOM)—these small molecules (e.g., amino acids, monosaccharides) are used in other respiratory processes by bacteria in sediments. H = HMW DOM, P = polymeric LMW DOM (pLMW DOM), = rate constant for HMW DOM consumption, Ap = rate constant for pLMW DOM consumption, and a = fraction of HMW DOM consumption that passes through the pLMW DOM pool. (Modified from Burdige, 2002.)...

Sialic acids are a family of nine-carbon acidic monosaccharides based on 3-deoxy nonulosonic acid (Fig. 17.4, also see Chapter 5). In 1952, the biochemist Gunnar Blix introduced the term sialic acid from the Greek aaXia (salia) or saliva after isolating this molecule from the salivary gland mucin. Sialic acid is now the generic term for the family that includes derivatives with a C5-amino substituent called neuraminic acid. Neu5Ac (5) is the type of sialic acid found in humans [47],... 

Glucuronic acid and sialic acid are normally present in conjugated forms. After degradation of these components in lysosomes, the free monosaccharides are released by a specific membrane transport system. The lysosomal sialic acid transporter from rat liver has been purified to apparent homogeneity in a reconstitutively active form. The transporter recognized structurally different types of acidic monosaccharides such as sialic acid, glucuronic acid, and iduronic acid. The transport was proton gradient dependent, and saturable with a of approximately 0.4mM [211]. 

The cells grown in high density culture medium at SO C were analyzed for protein, carbohydrate, lipid and vitamins. Amino acid, monosaccharide and fatty acid compositions were also determined. 

Disaccharides Like amino acids, monosaccharides can be linked together by a condensation reaction in which water is released. When two monosaccharides bond together, a disaccharide is formed. See Figure 24-9. The new bond formed is an ether functional group (C — O — C). Where does the water that is produced in this reaction come from ... 

Aliphatics HO-acids Monosaccharides Sugar Disaccharides Trisaccharides... 

Lysosomal accumulation of free sialic acid occurs in two phenotypically distinct inherited metabolic disorders, Salla disease and infantile sialic acid storage disease [1096]. Salla disease is an autosomal recessive lysosomal storage disorder and was first observed in patients of Fiimish ancestry, but also occurs outside Finland. The clinical symptoms are a slow progressive psychomotor retardation, impaired speech, ataxia and a prolonged course. Sialic acid accumulates in the lysosomes due to a defective efflux into the cytosol. The genetic defect affects the function of the specific transport protein for sialic acid and other acidic monosaccharides in the lysosomal membrane [1097]. The Salla disease locus... 

Acidic monosaccharides can be separated by an ion-exchange chromatography, and several automated systems have been developed (Spiro, 1977 Davies et al., 1974). However, their application to the analysis of uronic acids in plant cell walls has been limited (Selvendran, 1975b Selvendran et al., 1975). 

Clues to other signals for attachment and invasion of the host by helminth parasites have come from work on fish parasites such as Acanthostomum brauni. Cercariae of A. brauni do not recognize small molecules such as amino acids, monosaccharides or electrolytes, but do respond to hyaluronic acid and glycoproteins for attachment (34). Penetration of the host is triggered by free fatty acids and mucus components present on the fish skin surface (35). 

Catabolism can be divided into four stages. The first stage of catabolism is called digestion. The reactants required for all life processes ultimately come from our diet. In that sense, we really are what we eat. In this first stage, fats, carbohydrates, and proteins are hydrolyzed into fatty acids, monosaccharides, and amino acids, respectively (Figure 25.1). 

In the second stage of catabolism, these hydrolysis products—fatty acids, monosaccharides, and amino acids—are converted to compounds that can enter the citric acid cycle. To enter the citric acid cycle, a compound must be either one of the compounds in the cycle itself (called a citric acid cycle intermediate), acetyl-CoA, or pyruvate. Acetyl CoA is the only non-citric acid cycle intermediate that can enter the cycle (Section 17.20) pyruvate can enter the citric acid cycle only because it can be converted to acetyl-CoA or to oxaloacetate, a citric acid cycle intermediate (Sections 25.4 and 25.5). Fatty acids are converted to acetyl-CoA, monosaccharides are converted to pyruvate via glycolysis (Figure 25.2), and amino acids are converted to acetyl-CoA, pyruvate, and/or citric acid cycle intermediates, depending on the amino acid. 

Anabolism can be thought of as the reverse of catabolism. In anabolism, acetyl-CoA, pymvate, and citric acid cycle intermediates are the starting materials for the synthesis of fatty acids, monosaccharides, and amino acids. These compounds are then used to form fats, carbohydrates, and proteins. The mechanisms utilized by biological systems to synthesize fats and proteins are discussed in Sections 19.21 and 27.13. 

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