Information storage molecules

How did the complex pathways that constitute metabolism evolve This question, a difficult one to address, was approached in Chapter 2. The current thinking is that RNA was an early biomolecule and that, in an early RNA world, RNA served as catalysts and information-storage molecules (Section 2.2.2). 

Nucleic acids are the fourth class of biological molecules that you will study. They are the information-storage molecules of the cell. This group of nitrogen-containing molecules got its name from the cellular location in which the molecules are primarily found— the nucleus. It is from this control center of cells that nucleic acids carry out their major functions. 

The current thinking is that RNA was an early biomolecule and that, in an early RNA world, RNA served as catalysts and information-storage molecules. 

Deoxyribonucleic acids (DNAs) Nucleic acids that function as genetic information storage molecules contain deoxyribose... 

Finally, phosphate s energy helps build the most important of all biomolecules, the long-term information storage molecule DNA and its sister molecule, the short-term information transfer molecule mRNA. There are four types of TP molecules, each of which matches one of the four letters in DNA. 

LB Films of Porphyrins and Phthalocyanines. The porphyrin is one of the most important among biomolecules. The most stable synthetic porphyrin is 5,10,15,20-tetraphenylporphyrin (TPP). Many porphyrin and phthalocyanine (PC) derivatives form good LB films. Both these molecules are important for appHcations such as hole-burning that may allow information storage using multiple frequency devices. In 1937 multilayers were built from chlorophyll (35). 

In retrospect it is easy to see that such structural irregularity is actually required for proteins to fulfill their diverse functions. Information storage and transfer from DNA is essentially linear, and DNA molecules of very different information content can therefore have essentially the same gross structure. In contrast, proteins must recognize many thousands of different molecules in the cell by detailed three-dimensional interactions, which... 

An information science research group devised a new model which could explain information storage in the prebiotic phase of the biogenesis process. They assume that layered double hydroxide (LDH) minerals acted as proto-RNA molecules on the young Earth about 4 billion years ago. This hypothesis relates to Cairns-Smith s genetic takeover thesis, which thus again became the subject of discussion. 

There are many potential molecules and possible routes to the synthesis of biomolecules that might form the basis of a primitive metabolism but thus far we have not addressed the question of information propagation or Darwinian evolution. Information storage must be contained within a sequence, such as words in a sentence or the base sequences within the genetic code, and that requires a polymerisation reaction, which is preferably autocatalytic to reproduce the information accurately. Peptides and nucleotides have this property, although the condensation reaction joining them together needs to be activated. 

The preparation and study of nanoparticles has attracted a remarkable academic and industrial research effort because of their potential applications, ranging from fundamental studies in quantum physics, fabrication of composite materials, information storage/optoelectronics, immunoassays, to catalysts. The precise control of size and chemical behavior (stabihty and reactivity) by means of the synthesis itself is still one of the main targets because the direct correlation of the new intriguing properties with the particle size which is just between a molecule and a bulk material [140]. 

The discovery that certain metalloxo clusters can sustain a remanent magnetization prompted interest in the synthesis of new single-molecule magnets as potential media for high-density information storage. Unfortunately, the broad... 

In this chapter, we will discuss the recent results regarding the development of molecular switches and logic gates toward information processing at the molecular level based on electroactive molecules and supramolecules. Also, we will illustrate the progress of application of electron donor-acceptor compounds in high-density information storage. 

INFORMATION STORAGE WITH ELECTRON D-A MOLECULES AND SUPRAMOLECULES... 

The division of function between DNA (genetic information storage) and protein (catalysis) was, according to the RNA world hypothesis, a later development. New variants of self-replicating RNA molecules developed, with the additional ability to catalyze the condensation of amino acids into peptides. Occasionally, the peptide (s) thus formed would reinforce the self-replicating ability of the RNA, and the pair—RNA... 

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