RT Journal Article SR Electronic(1) A1 Le, Ve Van A1 Ko, So-Ra A1 Lee, Sang-Ah A1 Jin, Long A1 Blom, Jochen A1 Ahn, Chi-Yong A1 Oh, Hee-MockYR 2021 T1 Cochlodiniinecator piscidefendens gen. nov., sp. nov., an algicidal bacterium against the ichthyotoxic dinoflagellate Cochlodinium polykrikoides JF International Journal of Systematic and Evolutionary Microbiology, VO 71 IS 11 OP SP 005124 DO https://doi.org/10.1099/ijsem.0.005124 PB Microbiology Society, SN 1466-5034, AB Harmful algal blooms caused by Cochlodinium polykrikoides result in enormous economic damage to the aquaculture industry. Biological control methods have attracted wide attention due to their environmental-friendliness. In this study, a novel algicidal bacterium, designated strain M26A2MT, was determined for its taxonomic position and was evaluated for its potential to mitigate C. polykrikoides blooms. Strain M26A2MT exhibited the highest 16S rRNA gene sequence similarity to the type strains of Planktotalea lamellibrachiae (97.3%), Halocynthiibacter namhaensis (97.2%), Pseudohalocynthiibacter aestuariivivens (96.8%) and Halocynthiibacter arcticus (96.4%) in the family Rhodobacteraceae . The predominant fatty acids were C10 : 0 3-OH and summed feature 8 (comprising C18 : 1 ω7c and/or C18 : 1 ω6c). The major polar lipids were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminolipid and three unidentified lipids. Q-10 was the respiratory quinone. Strain M26A2MT exerted significant algicidal activity against C. polykrikoides cells by destroying the membrane integrity and the photosynthetic system. Our findings suggest that strain M26A2MT shows a high potential to control outbreaks of C. polykrikoides. Based on the polyphasic characterization, strain M26A2MT is considered to represent a novel species within a novel genus of the family Rhodobacteraceae , for which the name Cochlodiniinecator piscidefendens gen. nov., sp. nov. is proposed. The type strain is M26A2MT (=KCTC 82083T=JCM 34119T)., UL https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/ijsem.0.005124