Haliea alexandrii sp. nov., isolated from phycosphere microbiota of the toxin-producing dinoflagellate Alexandrium catenella

摘要

A Gram-negative, aerobic, non-motile, non-spore-forming and rod-shaped bacterium, named strain LZ-16-2(T), was isolated from the phycosphere microbiota of the paralytic shellfish poisoning toxin-producing marine dinoflagellate Alexandrium catenella LZT09. Strain LZ-16-2(T) grew optimally at 28 degrees C at pH 6.5 and with 3% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain LZ-16-2(T) fell within the genus Haliea and was most closely related to Haliea salexigens DSM 19537(T), with which the new isolate exhibited 98.5% 16S rRNA, gene sequence similarity. The major respiratory quinone was Q-8. The predominant cellular fatty acids were C-17:1 omega 8c. summed feature 3 (C-16:1 omega 7c and/or C-16:1 omega 6c). summed feature 8 (C-18:1 omega 7c and/or C-18:1 omega 6c), C-17:1 omega 6c, C-11:0 3-OH and C-17:0. The major polar lipids were phosphatidylethanolamine. phosphatidylglycerol and diphosphatidylglycerol. The average nucleotide identity and in silico DNA-DNA genome hybridization relatedness values between strain LZ-16-2(T) and its closest relative, H. salexigens DSM 19537(T), were 92.8 and 55.1%, respectively. The DNA G+C content was 61.3 mol%. Differential phenotypic properties and phylogenetic distinctiveness distinguished strain LZ-16-2(T) from all other members of the genus Haliea. On the basis of the polyphasic characterization, strain LZ-16-2(T) represents a novel species of the genus Haliea, for which the name Haliea alexandrii sp. nov. is proposed. The type strain is LZ-16-2(T) (=KCTC 62344(T)=CCTCC AB2017229(T)).