Molecular machines function

Molecular Machines Use, for molecular machine functions, of gold and silica supports and the chemical mechanisms involved in the function (host-guest chemistry). 

In the 1950s, biologists (notably Francis Crick and James Watson) discovered the molecular basis for information coding in DNA and established that the workings of cells were molecular machines tvith understandable structure and function. Mathematician John von Neuman developed a mathematical theory of self-reproducing machines based on the biological theories. 

Richter OMH, Ludwig B. 2003. C)dochrDme c oxidase—Structure, function, and physiology of a redox-driven molecular machine. Rev Physiol Biochem Pharmacol 147 47-74. 

Another, promising avenue to understand silk protein conformation and assembly is the use of model peptides. Although not recent (Fraser and MacRae, 1973 Lotz et al., 1974), studies of silk-based peptide from chemical synthesis, DNA recombinant technology, and computer simulation (Anderson et al., 1994 Asakura et al., 2003 Fahnestock et al., 2000 Fossey et al., 1991 Heslot, 1998 Kaplan, 1998 Wilson et al., 2000) have shown that selected repeats of silk proteins can be transformable hydrogels, elastomers, or regular thermoplastics and that with a proper design they can function as diverse molecular machines (Altman et al., 2003 Heslot, 1998 Kaplan, 1998 Urry, 1998). 

Urry, D. W. (1998). Five axioms for the functional design of peptide-based polymers as molecular machines and materials Principles for macromolecular assemblies. Peptide Sri. 47, 167-178. 

Protein is an excellent natural nanomaterial for molecular machines. Protein-based molecular machines, often driven by an energy source such as ATP, are abundant in biology. Surfactant peptide molecules undergo self-assembly in solution to form a variety of supermolecular structures at the nanoscale such as micelles, vesicles, unilamellar membranes, and tubules (Maslov and Sneppen, 2002). These assemblies can be engineered to perform a broad spectrum of functions, including delivery systems for therapeutics and templates for nanoscale wires in the case of tubules, and to create and manipulate different structures from the same peptide for many different nanomaterials and nanoengineering applications. 

Product 129 containing a cyclopentene-based photochromic fragment was proposed as an axis of pseudorotaxane structures, which has potential for use in the construction of a prototype of molecular machines active as a functional stopper (08DP294). 

Examples of naturally occurring molecular machines and motors are already known. Proteins are the workhorses of cellular biology, performing functions such as transportation, communication, and structural maintenance. Some of these proteins have moving parts and act exactly like small machines. 

Dolezal P, Likic V, Tachezy J, Lithgow T (2006) Evolution of the molecular machines for protein import into mitochondria. Science 313 314-318 Dong J-S, Lai R, Nielsen K, Fekete CA, Qiu H-F, Hinnebusch AG (2004) The essential ATP-binding cassette protein Rlil functions in translation by promoting preinitiation complex assembly. J Biol Chem 274 42157-42168 Ellis JE, Setchell KD, Kaneshiro ES (1994) Detection of ubiquinone in parasitic and free-living protozoa, including species devoid of mitochondria. Mol Biochem Parasitol 65 213-224... 

The many thousands of proteins present in each cell are made within the ribosomes, which are able to read each specific mRNA that comes their way. While ribosomes appear as little more than blurred dots in most electron micrographs, the 15,000 ribosomes of one cell of E. coli represent one-fourth of the total mass of the cell. Eukaryotic cells contain many times more of these little molecular machines. When ribosomes were first observed in the early 1950s,1 3 nobody could imagine either their composition or their function. 

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