Abstract: The present invention provides a stable salt of 3?-phosphoadenosine 5?-phosphosulfate (PAPS) and a production method therefor. The present invention is directed to a stable salt of PAPS (amine salt), which is formed between PAPS and an amine compound, and to a method for producing a stable salt of PAPS, which includes adding an amine compound to an aqueous PAPS solution in an amount by mole equal to or greater than that of PAPS, and lyophilizing the resultant solution. The present invention has first realized production of a solid-form PAPS salt having considerably improved stability through a very simple technique. Since the thus-produced amine salt of PAPS is very stable, the salt can be stored or employed without taking much care about decomposition thereof at ambient temperature.

Abstract: A process for producing uridine diphosphate-N-acetylglucosamine (UDPAG) from uridylic acid (UMP) and N-acetylglucosamine by use of microorganism cells, characterized by adding N-acetylglucosamine kinase thereto. According to the present invention, UDPAG can be efficiently produced even when N-acetylglucosamine is used as a substrate.

Abstract: The present invention relates to a process for preparing sugar nucleotides from nucleotides and sugar derivatives by the use of yeast, characterized in that the reactions are conducted at 20.degree. C. or below. According to this process, even when the preparation is conducted on an enlarged scale, a reduction in the yield of a sugar nucleotide can be inhibited by a very simple means; lowering the reaction temperature 20.degree. C. or below. Thus, the process is an extremely practical one applicable to the mass-production of sugar nucleotides.