The aim of this contribution is to explore the feasibility of this models starting from the assumption that all the involved processes can be efficient as needed. In particular, the questions we asked are: under the best experimental conditions, can the ribocell reaches a stationary CX-5461 ic50 condition where it oscillates continuously between two states after an before the splitting? Is there a concentration threshold for the genetic material to avoid

that the daughters cell remain without the minimal genetic kit to be alive? Or, in other worlds, how much is this model robust to random fluctuations ? We try to answer to these questions in the perspective of the more general problem of building up a minimal cell (Luisi et al. 2006a,

b) coupling an internal metabolic network that produce lipids (Mavelli & Ruiz-Mirazo 2006) with the dynamics of the vesicle membrane (Mavelli & Ruiz-Mirazo 2007a, b). Luisi, P.L., Chiarbelli, C, Stano, P. (2006b). From Never Born Proteins to Minimal Living Cells: Two Projects in Synthetic Biology. Orig.Life Evol. Biosphere 36, 605–616. Luisi, P.L., Ferri, F, Stano, P. (2006a). Approaches to semi-synthetic minimal cells: a review. Naturwissenschaften 93, 1–13. Mavelli F., Ruiz-Mirazo, K. (2006) Stochastic simulations of minimal self-reproducing cellular systems. Phil. Trans. R. Soc. B, 362, 1789–1802. Mavelli, F., Ruiz-Mirazo, K. (2007a). Bridging the gap between Selleckchem GSK872 in vitro and in silico approaches to minimal cells. Orig.Life Evol. Biosphere 37, 455–458. Mavelli, F., Ruiz-Mirazo, K. (2007b). Stochastic Simulation of fatty-acid

proto cell models. In: Sergey M. Bezrukov, editor, Noise and Fluctuations in Biological, Biophysical, and Biomedical Systems. vol. 6602, pages: 1B1–1B10. SPIE Bellingham, Washington. Szostak, J.W., Bartel, D.P., Luisi, P.L. (2001). Synthesizing life. Nature, 409, 387–390. E-mail: mavelli@chimica.​uniba.​it Selleck Neratinib The Origin of nTP: GTP for Information and ATP for Energy Ken Naitoh Waseda University, Faculty of CB-839 Science and Engineering, Tokyo, Japan The reason why adenosine triphosphate (ATP) is naturally selected as the main energy-carrier is not clarified. (Duve 2005) We examined the databases (Benson 2003, Lowe 1997, Nakamura 2000, DNA databank of Japan, JCM On-line catalogue) in order to clarify whether guanosine triphosphate (GTP) is mainly used as information storage in ribonucleic acids (RNAs), because adenine–uracil (A-U) pair in weaker connections would be dropped out relatively among candidates of information carriers. Actual frequencies of G-C pairs in the RNAs of hyper-thermophiles are much more than those of A-U pairs. (Naitoh 2005) The A-U pairs are less than G-C pairs also in RNAs of microorganisms such as Yeast preferring lower temperatures.