A new zoarcid fish, Andriashevia natsushimae (Japanese name: Natsushimachojyagenge), is described on the basis of 2 specimens collected in Sagami Bay, Japan, at the depth of 850 m. This species has no pectoral fins and no pelvic fins, indicating it to be Andriashevia. It has a round body and a moderate-sized mouth in contrast to Andriashevia aptera which has a flat body and a large mouth. Phylogenic tree based on 16S ribosomal RNA (16S rRNA) sequence indicates the species had diverted at the early stage in the evolution of eelpouts.

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Pyrobaculum islandicum is an ananaerobic hyperthermophilic archaeon that grows optimally at 100°C. We purified a NADH dehydrogenase from the membranes to homogeneity as analyzed by SDS-PAGE. The purified protein was suggested to comprise five subunits with molecular masses of 39 kDa, 37 kDa, 34 kDa, 31 kDa and 27 kDa, by SDS-PAGE analysis. The molecular mass of the native protein was estimated to be about 160 kDa by gel-filtration analysis. The optimal pH and temperature were 7.0 and above 80°C, respectively. The enzyme activity was shown to be highly specific to NADH, and the activity with NADPH was only 1.7% of the value with NADH.

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A NADPH dehydrogenase was purified from the hyperthermophilic archaeon, Pyrobaculum islandicum. The membrane protein was solubilized by treatment with 1% Tween 20, and purified 258-fold from the cell-free extract to homogeneity as judged by SDS-PAGE analysis. The molecular mass of the enzyme was revealed to be 41 kDa both by SDS-PAGE and gel filtration analyses. The optimal pH and temperature were 7.0 and above 80°C, respectively. The K_m and V_max values were 0.69 mM and 0.25 nmol/min, respectively. It was suggested that NADPH is an electron donor in the P. islandicum electron transfer system.

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