Open AccessHalobacteriovorax vibrionivorans sp. nov., a novel prokaryotic predator isolated from coastal seawater of China
Author(s) -
Xiao-Sheng Ye,
Mingxia Chen,
He-Yang Li,
Xiaoyu He,
Yan Zhao
Publication year - 2019
Publication title -
international journal of systematic and evolutionary microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.925
H-Index - 173
eISSN - 1466-5034
pISSN - 1466-5026
DOI - 10.1099/ijsem.0.003703
Subject(s) - biology , 16s ribosomal rna , strain (injury) , phylogenetic tree , genome , seawater , genus , microbiology and biotechnology , gene , genome size , gammaproteobacteria , whole genome sequencing , predator , zoology , genetics , ecology , predation , anatomy
Three prokaryotic predator strains, BL9 T , BL10 and BL28, were isolated with Vibrio alginolyticus from coastal seawater of PR China. Cells of the strains were Gram-negative, vibrioid-shaped and motile with a single sheathed flagellum (25-28 nm wide). Cells were around 0.3×0.5-1.0 µm in size. The three strains were obligate predators that exhibited a biphasic life cycle: a free-swimming attack phase and an intraperiplasmic growth phase within the prey. Bdelloplasts were formed. NaCl was required for growth. Optimum growth occurred at ~37 °C, with 2-4 % (w/v) NaCl and at pH 7.0-8.0. The results of phylogenetic analyses based on 16S rRNA gene sequences indicated that the three strains shared 99.9 % similarity to each other, were affiliated with the genus Halobacteriovorax in the class Oligoflexia , and represented the same new species. Strain BL9 T (=MCCC 1K03527 T =JCM 32962 T ) was designated as the type strain. Genome sequencing of strain BL9 T revealed a genome size of 3.14 Mb and a G+C content of 35.8 mol%. The estimated digital DNA-DNA hybridization (dDDH) values and the whole genome average nucleotide identity (gANI) values between the genome of strain BL9 T and those of Bdellovibrionales and Bacteriovoracales were 12.5-19 and 63.49-76.15 %, respectively. On the basis of life cycle features, results of physiological analyses, gANI data and dDDH data, strain BL9 T represents a new species within the genus Halobacteriovorax , for which the name Halobacteriovoraxvibrionivorans sp. nov. is proposed.