Biochemical tools

Resonance Raman Spectroscopy. If the excitation wavelength is chosen to correspond to an absorption maximum of the species being studied, a 10 —10 enhancement of the Raman scatter of the chromophore is observed. This effect is called resonance enhancement or resonance Raman (RR) spectroscopy. There are several mechanisms to explain this phenomenon, the most common of which is Franck-Condon enhancement. In this case, a band intensity is enhanced if some component of the vibrational motion is along one of the directions in which the molecule expands in the electronic excited state. The intensity is roughly proportional to the distortion of the molecule along this axis. RR spectroscopy has been an important biochemical tool, and it may have industrial uses in some areas of pigment chemistry. Two biological appHcations include the deterrnination of helix transitions of deoxyribonucleic acid (DNA) (18), and the elucidation of several peptide stmctures (19). A review of topics in this area has been pubHshed (20). 

Improving pressing and clarification, they are biochemical tools of first importance. 

Exogenous enzymes are used to produce fruit juices more easily during different stages of the process i.e. maceration, liquefaction or juice depectinisation These biochemical tools induce specific degradations that the processor can integrate into his process line to manage and valorize the fruits transformation into juice. 

It shonld not surprise us that quite distinct species nse some of the same molecules as pheromones. Remember that all extant life had a single common origin and that mnltiple biochemical pathways are shared by basically all living organisms. Thus, using mnch the same set of biochemical tools, multiple organisms have come to common solntions to common problems. This is one more example of the unity of life on Earth. 

As biochemical tools, suitable and sensible imino sugar modifications will certainly become helpful intelligent probes and reporters addressing some of the future needs of research in carbohydrate-active enzymes. 

Colchicine is a poisonous tricyclic tropane alkaloid from the autumn crocus (Colchicum autumnale) and gloriosa lily (Gloriosa superba). This alkaloid is a potent spindle fiber poison, preventing tubulin polymerization.25 Colchicine has been used as an effective anti-inflammatory drug in the treatment of gout and chronic myelocytic leukemia, but therapeutic effects are attainable at toxic or near toxic dosages. For this reason, colchicine and its analogs are primarily used as biochemical tools in the mechanistic study of new mitotic inhibitors. 

Our interest in expanding the acylative pyrrole annulation approach to additional heterocyclic systems has led to an efficient synthesis of pyrrolo[3,2-c]pyridin-2-ones and pyrido[3,4-6]pyrrolizidin-l-ones starting from 4-chloro-N-benzyl-2(l//)-pyridinone and amino acid salts.811 Over the years pyrrolo[3,2-c]pyridines (5-azaindoles)41 have been of interest for applications as elements in new drug design, nucleotide analogues,42 and biochemical tools. However, available synthetic routes to multifunctionalized members from this class of heterocyclic structures are limited.41 43... 

Peptide aldehydes are important biochemical tools for specific and reversible inhibition of serine, cysteine, and aspartate proteases in-vitro and in-vivo. Whereas several methods for the preparation of peptide aldehydes have been described [26-28], their reliable parallel synthesis remained a tedious endeavor. Peptide aldehydes suffer from configurational lability in the a-carbonyl position and from high chemical reactivity. 

Recently, Schultes Spasic, Mohanty and Bartel studied in exquisite detail the effects of monovalent and divalent cations on the conformation order of random RNA sequences [115, 116]. These authors investigated the following questions Can arbitrary RNA sequences fold into a unique structure Is this is an evolutionary property of RNA sequences [115, 116] Schultes et al. utilized biochemical tools, such as lead ion induced cleavage, ultracentrifugation, and gel electrophoretic mobility, to probe the structure of evolved and random RNA sequences [115, 116]. 

As a reflection of the important role of carboxylic acids in intermediary metabolism, compounds that serve as carboxylic acid mimics or as inhibitors of carboxylic acid processing enzymes have been extremely useful biochemical tools. A host of halogenated carboxylic acids have been synthesized and studied in this regard. Selected examples are given in this section. More extensive reviews are available52,53. 

Monoclonal and recombinant antibodies are broadly accepted for the diagnosis of various diseases, therapeutic applications, and as a general biochemical tool. 

The exploitation of these new microscale chemical and biochemical tools, based on microreactor chips, will eventually reap great rewards and bring new opportunities in micropreparation and analysis for drag discovery and development, biotechnology, as well as fundamental studies. 

Over 580 million years of evolution has followed the first suggestion of chemical differentiation resulting in an amazing number of biochemical tools for the production of secondary metabolites in marine invertebrates. 

The first identified member of this latter family was omuralide, the (3-lactone product of the Streptomyces-derived secondary metabolite lactacystin.32 34 Although omuralide was never developed by the pharmaceutical industry, it continues to be used as an important biochemical tool. Moreover, it served as a model for the synthetic analogue PS-519 (Figure 12.1), which was evaluated in Phase I clinical trials based on preclinical data that indicated a protective effect in models of cerebral ischaemia.35... 

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