Distributions of DNA and RNA Hydrolyzing Bacteria in Lakes and Their Extracellular Nuclease Production.

概要

論文の詳細を見る
The number of DNA and RNA hydrolyzing bacteria in the water of six lakes was found to range from 102 to 104 N⋅ml-1. They accounted for 8% to 67% of heterotrophic bacteria in the lake water. While the number of DNA and RNA hydrolyzing bacteria in the sediment of six lakes was found to range from 104 to 106 N⋅ml-1 and from 103 to 106 N⋅ml-1, respectively. They accounted for 6% to 50% of heterotrophic bacteria in the sediment. The distribution of both bacteria was correlated with the amount of chlorophyll a. The vertical distribution of DNA and RNA hydrolyzing bacteria in Lake Shinseiko reached maxima at a depth of 2m during the circulation period, and a maximum at a depth of 2m and at the surface layer for DNA and RNA hydrolyzing bacteria, respectively, during the stagnation period. The bacteria which could grow nourished solely by DNA or RNA were isolated from the sediment. They were identified as the genus Moraxella and Bacillus, respectively. When Moraxella sp. was incubated in synthetic medium containing DNA as the sole carbon source, extracellular DNase and alkaline phosphatase were detected in the medium, and DNA decomposion occurred, producing orthophosphate. In the case of Bacillus sp., extracellular RNase and alkaline phosphatase were detected, and the RNA decomposed to form orthophosphate.
日本陸水学会の論文