Isolation and characterization of a marine algicidal bacterium against the harmful raphidophyceae Chattonella marina.
A bacterial strain named AB-4 showing algicidal activity against Chattonella marina was isolated from coastal water of ULjin, Republic of Korea. The isolated strain was identified as Bacillus sp. by culture morphology, biochemical reactions, and homology research based on 16S rDNA. The bacterial culture led to the lysis of algal cells, suggesting that the isolated strain produced a latent algal-lytic compound. Amongst changes in algicidal activity by different culture filtrate volumes, the 10% (100 microl/ml) concentration showed the biggest change in algicidal activity; there, estimated algicidal activity was 95%. The swimming movements of Chattonella marina cells were inhibited because of treatment of the bacterial culture; subsequently, Chattonella marina cells became swollen and rounded. With longer exposure time, algal cells were disrupted and cellular components lost their integrity and decomposed. The released algicide(s) were heat-tolerant and stable in pH variations, except pH 3, 4, and 5. Culture filtrate of Bacillus sp. AB-4 was toxic against harmful algae bloom (HAB) species and nontoxic against livefood organisms. Bacillus sp. AB-4 showed comparatively strong activity against Akashiwo sanguinea, Fibriocapsa japonica, Heterosigma akashiwo, and Scrippsiella trochoidea. These results suggest that the algicidal activity of Bacillus sp. AB-4 is potentially useful for controlling outbreaks of Chattonella marina.
Kim
Yun Sook
YS
Department of Microbiology, Pukyong National University, Busan 608-737, Republic of Korea.
Lee
Dae-Sung
DS
Jeong
Seong-Yun
SY
Lee
Woe Jae
WJ
Lee
Myung-Suk
MS
D000898:Antibiosis / Q000502:physiology*; D001407:Bacillus / Q000302:isolation & purification / Q000502:physiology; D056890:Eukaryota / Q000378:metabolism*; D005068:Eutrophication; D006863:Hydrogen-Ion Concentration; D007723:Korea; D010802:Phylogeny; D010839:Phytoplankton / Q000378:metabolism; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013045:Species Specificity; D013696:Temperature; D014871:Water Microbiology
D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S