ABSTRACT
We already reported that 281 bp DNA was degraded to 5'-dNMP by treatment at 70 degrees C and pH 7.5 for 1 h in the presence of 10 mM Mn ions, and the detailed results are published on Biosci. Biotechnol. Biochem., Vol. 71, 2670-2679 (2007). The degradation was accelerated by 100 mM NaCl. More than 80 bp DNA prepared by PCR using human ZNF 219 cDNA as the template were degraded into 5'- dNMP. Fifty bp DNA prepared by PCR us- ing the synthetic F and R primers of 22 mer was degraded into unknown material besides dNMP. Single-strand 281 b DNA prepared by Strandase (Novagen) was suggested not to be degraded into dNMP but to be degraded into the unknown material. Only double-strand DNA is presumed to be degraded into dNMP, therefore the double-strand structure is considered to be necessary for the degradation into dNMP. Furthermore, the unknown material was found in the ppt. fraction after centrifugation of the reaction mixture in the case of 34mer only G oligomer, while 5'-dGMP were found not to be degraded into any material. The m/z of the unknown material prepared from 34mer only G oligomer was determined to be 266 by LC-TOFMS. The elucidation of the conversion mechanism is under investigation.
