Cairns Group

The use of reactive surfaces for the specific synthesis of biomolecules, or as a model for replication processes, was first reported by Cairns-Smith and Weiss (see Sect. 7.1) and continued by G. Wachtershauser (see Sect. 7.3), as well as J. Ferris and L. Orgel. It was thus appropriate to study the stabilisation of the reaction partners in enzyme-free self-replication at surfaces with reactive properties. As early as 1995, the group of G. von Kiedrowski (then at Freiburg, Germany) bonded reacting molecules at surfaces and then added the other required reaction components to the system in a stepwise manner (the latter process is referred to as feeding ). 

According to Cairns-Smith, the first primitive gene materials could have been clay minerals these crystallize out everywhere on Earth from dilute silica solutions and hydrated solutions of metal ions. Both groups of substances are continually being formed by weathering processes. Two cycles keep this dynamic process going ... 

Clays consist of parallel silicate layers in kaolinite, two unsymmetrical types of layers are linked by hydrogen bonds. One consists of aluminium ions and hydroxyl groups, the other of silicon and oxygen ions. Cairns-Smith does not postulate a detailed mechanism, but only describes the main thrust of his argument. Critics complain that clear experimental results are not available (however, other proponents of new hypotheses often provide no evidence to back up their suggestions ). 

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. 

Walsh, B.J., Hill, D.J., Macoun, R, Cairns, D., Howden, M.E.H. 2005. Detection of four distinct groups of hen egg allergens binding IgE in the sera of children with egg allergy. Allergol Immunopathol 33(4) 183—191. 

Donald Cairns is a member of the Royal Pharmaceutical Society of Great Britain (RPSGB), the Royal Society of Chemistry and the Association of Pharmaceutical Scientists. In 2006 he was appointed to the British Pharmacopoeia Commission and serves on an Expert Advisory Group of the Commission on Human Medicines. 

Cairns and Neustadter (1975) studied the stability of carbon dispersions stabilized by BP 45, a copolymer of methacrylic esters for which R in the ester group -COOR could be the straight chain C4 or Cg-iz alkyl groups, or the amino substituted ethyl group -CH2CH2NH2. They also studied the stabilizer PV30-TEPA, a succinimide terminated poly(isobutylene). Flocculation was induced by the addition of ethanol to the dispersion medium, which was n-heptane. Their results, which compare the CFVs with the 0-compositions determined by the method of Comet and van Ballegooijen (1966), are presented in Table 9.1. 

DE Graham, EL Neudstadter, A Stockwell, KP Whitting-ham, RJR Cairns. Symposium on Surface Active Agents. Society of Chemical Industries Colloids Surfaces Chemistry Group, London, 1979, pp 127. 

Atkinson read a Burial Service after which the tent was collapsed and a large snow cairn was erected on top of it. The members of the search party returned to Cape Evans on November 26 and were greatly relieved that Campbell and his men had returned in their absence from their winter-over on Inexpressible Island. The Terra Nova arrived at Cape Evans on January 18,1913, but before the remainder of Scott s second Antarctic expedition left Cape Evans, Atkinson and a group of men erected a cross on the summit of Observation Hill located directly behind McMurdo Station in order to commemorate the five men who died after reaching the geographic South Pole of Antarctica. The cross in Fig. 1.16 carries the names of the men who went to the pole (Captain Scott, Wilson, Bowers, Oats, and Evans) and an inscription selected by Cherry-Garrard (Bull and Wright 1993) ... 

The known in-vitro properties of DNA polymerizing enzymes do not provide an explanation of the in-vivo initiation of DNA synthesis (Kornberg, 1969 DeLucia and Cairns, 1969). Consider in-vitro polymerization of deoxyribonucleoside triphosphates by E, coli DNA polymerase. This enzyme catalyzes the addition of deoxyribonucleoside triphosphates to the 3 -hydroxyl terminus of a primer DNA. Such synthesis occurs only in the direction of 5 to 3 , and in all cases studied there is an absolute requirement for DNA template (Kornberg, 1969). The action of E, coli polymerase is illustrated in Figure 4. A DNA template must have an available 3 -hydroxyl terminated strand which can serve as a primer for the initiation of synthesis, and it is assumed that polymerase is bound to an area of the template strand near the 3 -end of the primer. The deoxynucleoside triphosphate is bound adjacent to the 3 -hydroxyl group of the terminal nucleotide to form a base pair with the template. When the correct base pair is formed the polymerase catalyzes a nucleophilic attack by the 3 -hydroxyl group of the primer on the a-phosphorus of the triphosphate. A phosphodiester bond is formed with the subsequent release of pyrophosphate (Fig. 4). 

Cairns and co-workers (52) introduced a functional group into poly(hexamethylene adipamide) (Nylon 66) by hydroxymethylating the polyamide backbone with formaldehyde and ammonia. Subsequent treatment with thiourea and hydrogen chloride gave an isothiuronium salt from which an alkali soluble polythiol could be obtained. 

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