CREATION OF GENETIC INFORMATION BY DNA-POLYMERASE OF THE ARCHAEON THERMOCOCCUS-LITORALIS - INFLUENCES OF TEMPERATURE AND IONIC-STRENGTH

DNA polymerase of the archaeon Thermococcus litoralis can synthesize a long stretch of linear double-stranded DNA in the complete absence of added primer and template DNAs. This finding suggests that genetic in formation can potentially be created by protein. We report here the ef fects of temperature, ionic strength and pi-i on this ab initio DNA sy nthesis by the protein in vitro. When the temperature of the reaction was changed, the sequence of the product DNA changed markedly. For ins tance, the reaction products were (TAAT)(n) at 69 degrees C, (TATCCGGA )(n) at 84 degrees C and (TATCGCGATAGCGATCGC). at 89 degrees C, The io nic strength of the reaction condition also affected the sequence: it was (TATCTAGA)(n) with 0 mM KCl, (TATATACG)(n) with 50 mM KCl and (TAT AGTTATAAC)(n) with 100 mM KCl at 74 degrees C, When the pH of the reac tion condition was changed from 6.8 to 10.8, the size of the product D NA decreased, but its sequence did not. These results demonstrate that DNA synthesized ab initio by DNA polymerase of T.litoralis is markedl y influenced by the reaction conditions, The results also suggest that genetic information that might have been created by protein on the ea rly earth is strongly influenced by environmental factors.