We have analyzed the microbial communities in the cold-seep sediment samples obtained from different depths (5800∼7500 m) of the Japan Trench land slope. The results indicated that the typical cold-seep microbial communities of bacteria and archaea were basically similar in different depth environments and consisted of the delta-Proteobacteria (including sulfate reducing bacterial group) as well as methanogenic archaea, which played an important role in sulfur circulation in the seep environment. More abundant microbes were also identified in deeper cold-seep environments. These observations suggested that the cold-seep activity at the deepest depths of the Japan Trench might be more dynamic than in the shallower land slope. This is the first suggestion describing the relationship between microbial mass and cold-seep activity.

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More than 80% of residual halophilic α-amylase (crude and purified) activity from strain S-1 was observed in the presence of various organic solvents. More than 78% remaining activity was detected after incubation for 120 hr in the presence of styrene, toluene, benzene or chloroform. Enzyme activity and stability with chloroform were higher than that without chloroform at the low or high temperature, and enzyme activity was higher in the presence of chloroform than one without chloroform when EDTA (5-15 mM) was added.

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