Molecular biology, living systems

With remarkable accuracy, Democritus in the fifth century B.C. set the stage for modem chemistry. His atomic theory of matter, which he formulated without experimental verification, still stands, more or less intact, and encapsulates the profound truth that nature s stunning wealth boils down to atoms and molecules. As science uncovers the mysteries of the world around us, we stand ever more in awe of nature s ingenious molecular designs and biological systems nucleic acids, saccharides, proteins, and secondary metabolites are four classes of wondrous molecules that nature synthesizes with remarkable ease, and uses with admirable precision in the assembly and function of living systems. 

Biochemistry can be defined as the science concerned with the chemical basis of life (Gk bios life ). The cell is the structural unit of living systems. Thus, biochemistry can also be described as the science concerned with the chemical constituents of living cells and with the reactions and processes they undergo. By this definition, biochemistry encompasses large areas of cell biology, of molecular biology, and of molecular genetics. 

Proteins are essential to all living systems. Proteins are macromolecules and, like all biological macromolecules, polymers (Alberts et al. 1994). The structural units of proteins (monomers) are about 20 amino acids. Although no clear line exists, proteins are generally considered to have minimal chain lengths of about 50 amino acids, corresponding to molecular masses near 5000 daltons. The most complicated proteins contain several thousand amino acids and have molecular masses of several million daltons. The functional diversity ranges from ... 

Deaner D. W. (1997). The first living systems a bioenergetic perspective. Microbiology and Molecular Biology Reviews 61 239. 

Fluorescence is also a powerful tool for investigating the structure and dynamics of matter or living systems at a molecular or supramolecular level. Polymers, solutions of surfactants, solid surfaces, biological membranes, proteins, nucleic acids and living cells are well-known examples of systems in which estimates of local parameters such as polarity, fluidity, order, molecular mobility and electrical potential is possible by means of fluorescent molecules playing the role of probes. The latter can be intrinsic or introduced on purpose. The high sensitivity of fluo-rimetric methods in conjunction with the specificity of the response of probes to their microenvironment contribute towards the success of this approach. Another factor is the ability of probes to provide information on dynamics of fast phenomena and/or the structural parameters of the system under study. 

Chemical Biology is one of the fastest areas of science as a multidisciplinary during this century. The interdisciplinary study of molecules in living systems at a health science campus helps to integrate the traditional disciplines of chemistry and biology by understanding the molecular mecharrisms of biological processes provides an opportunity to manipirlate them in a defined and predictable way. 

During the last two decades, chemists have become increasingly focused on how molecules interact, i.e. on supramolecular chemistry. Dynamic intermolecular processes provide opportunities for incorporation of control, adaptation and function in man-made materials, as observed in living systems. In biology, these processes are tightly controlled by the catalytic action of enzymes. In this chapter, we focus on enzymatically controlled supramolecular polymerisation, whereby self-recognising molecular building blocks assemble to form extended onedimensional (ID) structures, or supramolecular polymers, with unique adaptive features. 

Why are isotonic drinks useful Osmotic pressure in living systems is incredibly important yet how often is the topic dismissed or merely discussed as a means to measure molecular weight of polymers Why not consider polymers as biological macromolecules and add to the discussion that a balance of osmotic pressure keeps our cells from bursting - which goes back to why the isotonic sport drinks are useful Relevance in the examples used in our courses is possible. 

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