Numerous biological processes

This thiol-disulfide interconversion is a key part of numerous biological processes. WeTJ see in Chapter 26, for instance, that disulfide formation is involved in defining the structure and three-dimensional conformations of proteins, where disulfide "bridges" often form cross-links between q steine amino acid units in the protein chains. Disulfide formation is also involved in the process by which cells protect themselves from oxidative degradation. A cellular component called glutathione removes potentially harmful oxidants and is itself oxidized to glutathione disulfide in the process. Reduction back to the thiol requires the coenzyme flavin adenine dinucleotide (reduced), abbreviated FADH2. 

The CaR regulates numerous biological processes, including the expression of various genes (e.g., PTH) the secretion of hormones (PTH and calcitonin), cytokines (MCP-1), and calcium (e.g., into breast milk) the activities of channels (potassium channels) and transporters (aquaporin-2) cellular shape, motility (of macrophages), and migration cellular adhesion (of hematopoietic stem cells) and cellular proliferation (of colonocytes), differentiation (of keratinocytes), and apoptosis (of H-500 ley dig cancer cells) [3]. 

Phosphorus forms a wide variety of oxoanions, which outnumber those formed by any other element except silicon [ 1 ]. Many of these anionic hgands are of industrial importance and their derivatives are essential components of numerous biological processes. Some of the more common examples include orthophosphate PO " (1), phosphite HPO " (2) and metaphosphate PO3 (3). 

The higher sugars have been identified as subunits in various natural products, and it is now well recognized that they play prominent roles in numerous biological processes. For example, some seven- and eight-carbon-atom sugars are important... 

The other major arachidonic acid (AA) converting enzyme is an integral binding protein, 5-lipoxygenase, which is responsible for the initial transformation in a cascade of events towards the biosynthesis of leukotrienes. Leukotrienes are major mediators of numerous biological processes, including chemotaxis, and are implicated in hypersensitivity disorders like asthma. It was discovered in the early 1990s that another protein is necessary for the cellular synthesis of... 

It is clear that protein-carbohydrate interactions are essential in numerous biological processes and that the development of carbohydrate mimetics that interfere with these processes would provide a powerful methodology for both modulation and amelioration of specific biological activity. Since the early 1990s, novel... 

Hydroxamic acids are important bioligands and are involved in numerous biological processes including metal-ion transport and inhibition of metalloenzymes . 1 1 Metal binding to hydroxamic acids usually occurs in a bidentate fashion (Scheme 99) with... 

Carboxylic acids, compounds of the type RCOH, constitute one of the most frequently encountered classes of organic compounds. Countless natural products are carboxylic acids or are derived from them. Some carboxylic acids, such as acetic acid, have been known for centuries. Others, such as the prostaglandins, which are powerful regulators of numerous biological processes, remained unknown until relatively recently. Still others, aspirin for example, are the products of chemical synthesis. The therapeutic effects of aspirin, welcomed long before the discovery of prostaglandins, are now understood to result from aspirin s ability to inhibit the biosynthesis of prostaglandins. 

Redox reactions are ubiquitous and occur in numerous biological processes. In mitochondrial respiration, ATP production is coupled to electron transport. Electrons are transferred from complex I, II, III, and IV, through a series of redox reactions that create a proton gradient outside of the mitochondrial membrane allowing for the production of ATP. Redox reactions are also extremely important in metabolism. CYPs and FMOs rely on redox reactions for their catalytic function (see Chapter 10). 

Carbohydrates specifically mediate numerous biological processes that include cell adhesion and differentiation, pathogen invasion, tumor cell metastasis, and inflammatory responses and are therefore of great interest for the generation of therapeutics (/-i). Unfortunately, the molecular basis for most of... 

This Section is not only the most voluminous, but is also important because of the mechanisms of formation involved and the biochemical role of the compoimds in numerous biological processes. This Section describes at least four different kinds of nitrogen-containing derivatives of D-fructose. 

Like a gecko, fimbriated bacteria use multivalent contacts for adhesion. Moreover, multivalency is a general theme in biological systems and multivalent interactions are of importance for numerous biological processes, such as immune... 

Diversity of Ligand-Integrin Interactions Contributes to Numerous Biological Processes... 

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