Genus Aquimarina Research Articles

Bacterial Communities Associated with Lesions of Shell Disease in the American Lobster,Homarus americanusMilne-Edwards

Shell disease in Crustacea is a widely recognized syndrome having a polymicrobial etiology, and manifesting itself as lesions of the shell with a variable structure and shell location. We characterized major members of bacterial communities in epizootic shell disease lesions of the American lobster (Homarus americanus, Milne Edwards) and compared these communities with the ones found in study cases of impoundment and enzootic shell disease. Bacteria belonging to several Flavobacteriaceae genera (Aquimarina, Tenacibaculum, Polaribacter, Maribacter, Cellulophaga) within the phylum Bacteroidetes appear to have particular attraction to lobster lesions. The most prominent Bacteroidetes in lobster lesions were representatives of the genus Aquimarina sp., but only Aquimarina ‘homaria’ was detected in all analyzed lesions of epizootic, impoundment, and enzootic shell disease. It was found on 45% of surfaces unaffected by shell disease, but in smaller numbers compared with lesions. Alphaproteobacteria represent the most diverse class of proteobacteria found in both lesions and on unaffected surfaces. Three bacteria of this class appear to be ubiquitous in shell disease lesions, but only one specific alphaproteobacterium tentatively assigned to the genus Thalassobius (herein designated as ‘Thalassobius’ sp.) was present in all analyzed lesions of epizootic, impoundment, and enzootic shell disease. A ubiquitous gammaproteobacterium called ‘Candidatus Homarophilus dermatus’ was also prevalent in lesions, but just as commonly it was associated with surfaces unaffected by shell disease. The bacteria A. ‘homaria’ and ‘Thalassobius’ sp. are dominant and appear obligatory in lobster shell lesions, and are only occasionally detected on unaffected surfaces, which serve as intermediate reservoirs for the two potential pathogens. Therefore, these two bacteria stand out as potential shell-disease pathogens.

Draft Genome Sequence of the Novel Agarolytic Bacterium Aquimarina agarilytica ZC1

The marine bacterium ZC1 is the type strain of the recently identified novel species Aquimarina agarilytica. It can produce multiple agarases. Here we report the draft genome sequence of strain ZC1 (4,253,672 bp, with a GC content of 32.8%) and major findings from its annotation. It is the first reported genome in the genus Aquimarina.

Aquimarina salinaria sp. nov., a novel algicidal bacterium isolated from a saltpan

A bacterial strain designated antisso-27(T), previously isolated from saltpan in Taiwan while screening for bacteria for algicidal activity, was characterized using the polyphasic taxonomic approach. Strain antisso-27(T) was Gram-negative, aerobic, brownish yellow colored, rod-shaped, non-flagellated and non-gliding. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain antisso-27(T) belonged to the genus Aquimarina within the family Flavobacteriaceae with relatively low sequence similarities of 94.0-96.6% to other valid Aquimarina spp. It contained iso-C(17:0) 3-OH, iso-C(15:0), iso-C(16:0), iso-C(15:1) and iso-C(15:0) 3-OH as the main fatty acids and contained a menaquinone with six isoprene units (MK-6) as the major isoprenoid quinone. Major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, an uncharacterized aminolipid and five uncharacterized phospholipids. Strain antisso-27(T) employed direct mode of algicidal lysis to Chlorella vulgaris strain 211-31; nevertheless, it released an algicidal substance against M. aeruginosa strain MTY01. This is the first study that the Aquimarina species possesses both direct and indirect algicidal activities. On the basis of the phylogenetic and phenotypic data, strain antisso-27(T) should be classified as representing a novel species, for which the name A. salinaria sp. nov. is proposed. The type strain is A. salinaria antisso-27(T) (=BCRC 80080(T)=LMG 25375(T)).

Novel l-amino acid oxidase with algicidal activity against toxic cyanobacterium Microcystis aeruginosa synthesized by a bacterium Aquimarina sp.

A brownish yellow pigmented bacterial strain, designated antisso-27, was recently isolated from a water area of saltpan in Southern Taiwan. Phylogenetic analyses based on 16S rRNA gene sequences indicate that strain antisso-27 belongs the genus Aquimarina in the family Flavobacteriacea and its only closest neighbor is Aquimarina spongiae (96.6%). Based on screening for algicidal activity, strain antisso-27 exhibits potent activity against the toxic cyanobacterium Microcystis aeruginosa. Both the strain antisso-27 bacterial culture and its culture filtrate show algicidal activity against the toxic cyanobacterium, indicating that an algicidal substance is released from strain antisso-27. The algicidal activity of strain antisso-27 occurs during the late stationary phase of bacterial growth. Strain antisso-27 can synthesize an algicidal protein with a molecular mass of 190 kDa, and its isoelectric point is approximately 9.4. This study explores the nature of this algicidal protein such as l-amino acid oxidase with broad substrate specificity. The enzyme is most active with l-leucine, l-isoleucine, l-methionine and l-valine and the hydrogen peroxide generated by its catalysis mediates algicidal activity. This is the first report on an Aquimarina strain algicidal to the toxic M. aeruginosa and the algicidal activity is generated through its enzymatic activity of l-amino acid oxidase.

Aquimarina addita sp. nov., isolated from seawater

An orange-coloured, rod-shaped, non-motile, Gram-reaction-negative, strictly aerobic bacterial strain, designated JC2680(T), was isolated from a seawater sample of Jeju Island, Korea. The isolate required sea salts for growth. Flexirubin-type pigments were absent. 16S rRNA gene sequence analysis indicated that the test strain belonged to the genus Aquimarina within the family Flavobacteriaceae, but shared relatively low levels of similarity (93.6-95.9 %) with the type strains of recognized Aquimarina species. The predominant cellular fatty acids [iso-C(17 : 0) 3-OH, iso-C(15 : 0) and summed feature 9 (comprising 10-methyl C(16 : 0) and/or iso-C(17 : 1)ω9c) and DNA G+C content (35 mol%) were consistent with the assignment of strain JC2680(T) to the genus Aquimarina. However, a number of phenotypic characteristics, namely inability to grow under microaerophilic conditions, differences in enzyme reactions, and absence of flexirubin-type pigments and gliding motility, clearly distinguished strain JC2680(T) from recognized species of the genus Aquimarina. The data presented thus indicate that strain JC2680(T) represents a novel species of the genus Aquimarina, for which the name Aquimarina addita sp. nov. is proposed. The type strain is JC2680(T) ( = KACC 14156(T) = JCM 17106(T)).

Aquimarina litoralis sp. nov., isolated from a coastal seawater

A strictly aerobic, red-pigmented, non-motile, catalase- and oxidase-positive, Gram-staining-negative bacterium, designated strain CNURIC011(T), was isolated from seawater off the coast of Jeju Island in Korea. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain CNURIC011(T) belongs to the genus Aquimarina in the family Flavobacteriaceae. 16S rRNA gene sequence analysis revealed that the close relatives of the novel strain are Aquimarina latercula ATCC 23177(T), Aquimarina marcrocephali JAMB N27(T), Aquimarina intermedia KMM 6258(T), Aquimarina muelleri KMM 6020(T), and Aquimarina brevivitae SMK-19(T), with sequence similarities of 97.6, 96.6, 96.0, 95.6, and 94.2%, respectively. DNA-DNA hybridization revealed that the level of relatedness between strain CNURIC011(T) and Aquimarina latercula ATCC 23177(T) (=KCTC 2912(T)) was 4.9%. The DNA G+C content was 35.8 mol% and the major respiratory quinone was MK-6. The major fatty acids were iso-C(15:0) (14.9%), C(15:0) (13.9%), iso-C(17:0) 3-OH (12.6%), iso-C(15:1) G (7.3%), and iso-C(17:1) omega9c (7.2%). On the basis of phenotypic, phylogenetic, and genotypic data, strain CNURIC011(T) represents a novel species within the genus Aquimarina, for which the name Aquimarina litoralis sp. nov. is proposed. The type strain is CNURIC011(T) (=KCTC 22614(T) =JCM 15974(T)).

Aquimarina spongiae sp. nov., isolated from marine sponge Halichondria oshoro

A Gram-stain-negative, yellow-pigmented, rod-shaped, strictly aerobic, non-flagellated, non-gliding and oxidase- and catalase-positive bacterium, designated A6(T), was isolated from a marine sponge, Halichondria oshoro, collected on the coast of Jeju Island, South Korea. Phylogenetic analysis based on the nearly complete 16S rRNA gene sequence revealed that strain A6(T) was a member of the family Flavobacteriaceae. The closest relatives were Aquimarina intermedia LMG 23204(T), A. latercula ATCC 23177(T), A. brevivitae SMK-19(T) and A. muelleri KMM 6020(T), with which strain A6(T) shared 95.7, 95.1, 94.7 and 94.6 % 16S rRNA gene sequence similarity, respectively. The dominant fatty acids of strain A6(T) were iso-C(15 : 0) (32.2 %), iso-C(17 : 0) 3-OH (20.0 %), iso-C(15 : 0) 3-OH (12.3 %), iso-C(15 : 1) G (7.2 %) and summed feature 3 (comprising iso-C(15 : 0) 2-OH and/or C(16 : 1)ω7c; 6.8 %). The DNA G+C content of strain A6(T) was 36.0 mol% and the major respiratory quinone was MK-6. On the basis of combined phenotypic and phylogenetic analyses, strain A6(T) represents a novel species of the genus Aquimarina, for which the name Aquimarina spongiae sp. nov. is proposed. The type strain is A6(T) (=KCTC 22663(T) =DSM 22623(T)).

Aquimarina macrocephali sp. nov., isolated from sediment adjacent to sperm whale carcasses

A Gram-negative, rod-shaped, non-spore-forming, strictly aerobic strain with gliding motility, designated JAMB N27(T), was isolated from sediment adjacent to sperm whale carcasses off Kagoshima, Japan, at a depth of 219 m. Strain JAMB N27(T) contained MK-6 as the major isoprenoid quinone and iso-C₁₅:₀, iso-C₁₅:₁, C₁₆:₁ and iso-C₁₇:₁ as the predominant fatty acids. Casein, chitin, gelatin and starch were degraded. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain JAMB N27(T) represented a separate lineage within the genus Aquimarina. The DNA G+C content of strain JAMB N27(T) was 33.1 mol%. DNA-DNA relatedness values between strain JAMB N27(T) and type strains of species of the genus Aquimarina were significantly lower than the cut-off value accepted for the definition of a novel species. Therefore, strain JAMB N27(T) represents a novel species, for which the name Aquimarina macrocephali sp. nov. is proposed. The type strain is JAMB N27(T) (=JCM 15542(T)=NCIMB 14508(T)).

Aquimarina intermedia sp. nov., reclassification of Stanierella latercula (Lewin 1969) as Aquimarina latercula comb. nov. and Gaetbulimicrobium brevivitae Yoon et al. 2006 as Aquimarina brevivitae comb. nov. and emended description of the genus Aquimarina

A heterotrophic, aerobic, Gram-negative, pigmented and gliding bacterium, strain KMM 6258(T), was isolated from the sea urchin Strongylocentrotus intermedius and investigated using a polyphasic taxonomic approach. 16S rRNA gene sequence analysis revealed that the closest relatives of the novel strain are Aquimarina muelleri, Stanierella latercula and Gaetbulimicrobium brevivitae, members of the family Flavobacteriaceae, with sequence similarities of 96.3, 96.4 and 96.2 %, respectively. Phylogenetic evidence, supported by chemotaxonomic and phenotypic data, assigned strain KMM 6258(T) to the genus Aquimarina as Aquimarina intermedia sp. nov. (type strain KMM 6258(T)=DSM 17527(T)=JCM 13506(T)=LMG 23204(T)). The reclassification of Stanierella latercula as Aquimarina latercula comb. nov. and Gaetbulimicrobium brevivitae as Aquimarina brevivitae comb. nov. is proposed.

Description of Aquimarina muelleri gen. nov., sp. nov., and proposal of the reclassification of [Cytophaga] latercula Lewin 1969 as Stanierella latercula gen. nov., comb. nov.

The taxonomic position of three novel sea-water isolates was determined. The strains studied were strictly aerobic, heterotrophic, pigmented, motile by gliding, Gram-negative and oxidase-, catalase-, beta-galactosidase- and alkaline phosphatase-positive. 16S rRNA gene sequence phylogenetic analysis indicated that the strains KMM 6020T, KMM 6021 and KMM 6028 occupied a distinct lineage within the family Flavobacteriaceae. The major respiratory quinone was MK-6. The predominant fatty acids were i15 : 0, i15 : 1, i15 : 0 3-OH, i17 : 1omega9c and i17 : 0 3-OH. On the basis of phenotypic, chemotaxonomic, genotypic and phylogenetic characteristics, the novel bacteria were assigned to the genus Aquimarina gen. nov., as Aquimarina muelleri gen. nov., sp. nov. The type strain is KMM 6020T (=KCTC 12285T=LMG 22569T). From the results of the 16S rRNA gene sequence analysis and phenotypic features, the species [Cytophaga] latercula Lewin 1969 is proposed to be reclassified in the new genus Stanierella as Stanierella latercula gen. nov., comb. nov., with type strain CIP 104806T (=ATCC 23177T=NCIMB 1399T=LMG 1343T).