| 摘要 |
<p>PURPOSE:To prepare 5'-guanylic acid from 5'-xanthylic acid and ammonia, by using a transformed strain of Escherichia coli containing quanylic acid synthetase gene. CONSTITUTION:Escherichia coli capable of producing 5'-guanylic acid from 5'- xanthylic acid and ammonia and/or L-glutamin, capable of converting adenosine phosphate into adenosine triphosphate by the use of an energy donor except phosphorus oxide to give 5'-guanylic acid. The above-mentioned Escherichia coli is given as a transformed strain. For example, a fragment of DNA containing guanylic acid synthetase gene is inserted into a tetracycline resistance site of plasmid pBR322, tryptophan promotor is connected to the upper stream of the gene to give plasmid (pXA10), K294 strain is transformed with the plasmid to give E.coli K294. E.coli K294 and/or pXA10 strain may be cited as the Escherichia coli.</p> |
