Isolation and Identification of a Microcystin-degrading Assistant Bacterium

Abstract:

A bacterial strain was enriched and isolated from rotten cyanobacteria of Taihu Lake by dilution-plate method, using microcystins as selective material of microcystin-degrading bacteria, which was extracted and purified from cells of cyanobacteria. Based on morphological, physiological characteristics and 16S rDNA sequence analysis, the strain is preliminarily identified as Micrococcus luteus (GenBank accession number is GQ143751). The results of microcystin-degrading experiments show that the strain could hardly degrade microcystins but could enhance the microcystin-degrading capability of another strain Stenotrophomonas acidaminiphila. When the strain is mixed with Stenotrophomonas acidaminiphila, the microcystin-degrading capability of mixed bacteria is improved 66.7% compared with Stenotrophomonas acidaminiphila.

Key words:Microcystins, Biodegradation, Assistant bacteria, Micrococcus luteus