| Título: | The origin of life did it occur at high temperatures? |
| Autores: |
Miller, SL Lazcano Araujo Reyes, Antonio Eusebio |
| Fecha: |
20130312T14:38:29Z 20130312T14:38:29Z 1995 |
| Publicador: | Facultad de Ciencias - UNAM |
| Fuente: |
 |
| Tipo: | Artículo de investigación |
| Tema: |
Biochemistry & Molecular Biology Evolutionary Biology Genetics & Heredity origin of life hyperthermophiles heat shock proteins submarine hydrothermal vents RNA world primitive atmosphere preRNA world |
| Descripción: | A hightemperature origin of life has been proposed, largely for the reason that the hyperthermophiles are claimed to be the last common ancestor of modern organisms. Even if they are the oldest extant organisms, which is in dispute, their existence can say nothing about the temperatures of the origin of life, the RNA world, and organisms preceding the hyperthermophiles. There is no geological evidence for the physical setting of the origin of life because there are no unmetamorphosed rocks freom that period. Prebiotic chemistry points to a lowtemperature origin because most biochemicals decompose rather rapidly at temperatures of 100 degrees C (e.g., halflives are 73 min for ribose, 21 days for cytosine, and 204 days for adenine). Hyperthermophiles may appear at the base of some phylogenetic trees because they outcompeted the mesophiles when they adapted to lower temperatures, possibly due to enhanced production of heatshock proteins. |
| Idioma: | Inglés |