Primitive meteorites, known as carbonaceous chondrites contain a few wt.% of organic carbon, including complex macromolecular organic matter, as well as building-blocks of life such as amino acids. Some of them could have been contributed to the emergence of life in the early earth. How these meteoritic organic compounds were originated? Liquid water is known to have presented for millions of years in early evolutional stage of some asteroids, i.e., planetesimals. We have been working on hydrothermal experiments and shown that various amino acids are produced simultaneously with macromolecular organic solids from simple molecules such as formaldehyde and ammonia. Here I review the experimental simulations for formations of various organic compounds in planetesimal aqueous environments and discuss future perspectives.

  What role did “proteins” play in origin of life? To unveil such long-standing mystery, we pay attention to the self-assembling ability of peptides as well as direct metal-binding. It has been reported that several proteins undergo misfolding to form insoluble fibrous aggregates. These fibrous proteins have been considered as bio-nanomaterials due to their thermal stability and specific repeat structures, while they involved in Alzheimer’s disease and Parkinson’s disease. The fabrication of high-level hierarchical structure by self-assemble of peptides is exactly reminiscent of evolutional pathway beyond ordinary chemical compounds. It has already reported that the amyloid-forming peptides designed form efficient catalysts of ester hydrolysis and oxidation. This observation implies a potential relationship between amyloid aggregate and the emergence of protein catalysts during the evolution of metalloenzymes.