Carbohydrates and nucleic acids

We ll see numerous instances in future chapters where the chemistry of a given functional group is strongly affected by being in a ring rather than an open chain. Because cyclic molecules are so commonly encountered in all classes of bioniolecules, including proteins, lipids, carbohydrates, and nucleic acids, it s important that the effects of their cyclic structures be understood. 

This volume of Topics in Current Chemistry aims to highlight major developments in the field and it shows the efforts of chemists from various subdisciplines of chemistry to design new dendritic molecules focusing on novel properties, functions, and potential applications. Hyperbranched/dendritic molecules containing silicon, phosphorus, and other elements are reported apart from hydrocarbon, carbohydrate and nucleic acid cascade molecules. 

Carbohydrates not only interact with protein receptors, but also with other carbohydrates and nucleic acids. Recently, gold nanoparticles (GNPs) have been prepared as new multivalent tools that mimic carbohydrate presentation on the cell surface. Using this tool, a weak calcium-mediated carbohydrate-carbohydrate interaction has been detected using NMR, employing... 

Proteins, carbohydrates, and nucleic acids Organic reactions... 

Stereochemistry is the chemistry of molecules in three dimensions. A clear understanding of stereochemistry is crucial for the study of complex molecules that are biologically important, e.g. proteins, carbohydrates and nucleic acids, and also drug molecules, especially in relation to their behaviour and pharmacological actions. Before we go into further detail, let us have a look at different types of isomerism that may exist in organic molecules. 

Phosphatidylinositol Synthesis. The symptoms of inositol depletion include a decreased hyphal extension rate, increased branching and cell lysis. Other changes occur in protein, carbohydrate and nucleic acid metabolism, and reduced activity levels of membrane-bound wall biosynthetic enzymes.7... 

Water is not just the solvent in which the chemical reactions of living cells occur it is very often a direct participant in those reactions. The formation of ATP from ADP and inorganic phosphate is an example of a condensation reaction in which the elements of water are eliminated (Fig. 2-22a). The reverse of this reaction— cleavage accompanied by the addition of the elements of water—is a hydrolysis reaction. Hydrolysis reactions are also responsible for the enzymatic depolymerization of proteins, carbohydrates, and nucleic acids. Hydrolysis reactions, catalyzed by enzymes called... 

Many groups in proteins, carbohydrates, and nucleic acids form hydrogen bonds to one another and to surrounding water molecules. For example, an imidazole group of a protein can bond to an OH group of an amino acid side chain or of water in the following ways ... 

Isoniazid (INH, Laniazid, Nydrazid, other names) is one of the primary drugs used to treat tuberculosis.24,61 Although the exact mechanism of action is unknown, this drug appears to interfere with several enzymatic pathways involving protein, lipid, carbohydrate, and nucleic acid metabolism in susceptible bacteria. Adverse reactions to isoniazid are common, and patients may develop disorders such as hepatitis and peripheral neuropathies. 

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