The nucleotide sequence of 1981 bp cDNA containing the entire coding region of a human placental fructose-6-phosphate,2-kinase/fructose-2,6-bisphosphatase was determined. The sequence encodes 469 amino acids and, based on homology to the rat testis enzyme, appears to be the testis-type isozyme expressed in placenta. The enzyme was expressed in Escherichia coli BL21 (DE3) by using a T7 RNA polymerase-based expression system and purified to homogeneity. The expressed enzyme was bifunctional with specific activities of 75 and 80 mU/mg of kinase and phosphatase, respectively. Kinetic parameters of the expressed enzyme are similar to those of the rat testis enzyme.

In recent years, in Japan fireflies (Luciola) have attracted attention as a barometer of water side environments and numerous activities have been undertaken to protect them. However, in many cases the protection of fireflies has met with failure and it remains difficult for fireflies to generate spontaneously.There are many conditions required for fireflies to live and it is very hard to express such conditions in figures. Therefore it is difficult to estimate their living conditions by numerical analysis.In the first part of this research, the present state of generation and living of the fireflies known as genjibotaru in the Kanto district are investigated. Next, the authors divide the living conditions into three items: flow condition, water quality condition and environment condition. For the numerical analysis for each item, quantification are applied. As a result, the effective living conditions for genjibotaru are established. The results will be great interest to people concerned with the protection of the river environment.