The crucial step in assembling amino acids into the proteins that are central to living organisms is the formation of peptide bonds.  Amino acids are found even in meteorites and seem to form abiogenically with some ease.  Peptide bonds link simple amino acids into long chains that are the essence of complex proteins, but this does not happen spontaneously.  The bonds form in the presence of carbon monoxide, but require some kind of catalysis.  Researchers at the University of Munich, Germany have discovered that very fine-grained precipitates of iron and nickel sulphides readily perform such catalytic functions (Huber, C. et al. 2003.  A possible primordial peptide cycle.  Science, v.  301, p. 938-940).  This tallies nicely with one of the co-workers’ (Günter Wächtershäuser) hypothesis for the chemoautotrophic origin of life near sea-floor hydrothermal vents, where Fe, Ni and S are abundant, as is CO in the hot water that emanates from them.