Screening, identification and desilication of a silicate bacterium

Abstract

The strain Lv_1–2 isolated from the Henan bauxite was characterized by morphological observation, biochemical and physiological identification, and 16S rDNA sequence analysis. The influences of temperature, initial pH value, the volume of medium, shaking speed and illite concentration on the desilicating ability of the strain Lv_1–2 were investigated. The results show that the bacterium is a Gram-negative rod-shaped bacterium with oval endspores and thick capsule, but without flagellum. The biochemical and physiological tests indicate that the strain Lv_1–2 is similar to Bacillus mucilaginosus. In GenBank the 16S rDNA sequence similarity of the strain Lv_1–2 and the B. mucilaginosus YNUCC0001 (AY571332) is more than 99%. Based on the above results, the strain Lv_1–2 is identified as B. mucilaginosus. The optimum conditions for the strain Lv_1–2 to remove silicon from illite are as follows: temperature is 30 °C; initial pH value is 7.5; medium volume in 200 mL bottle is 60 mL; shaking speed of rotary shaker is 220 r/m; illite concentration is 1%.

Keywords

screening / identification / Bacillus mucilaginosus / silicon removal