menaquinone-6 and Fish-Diseases

A Gram-stain positive, pleomorphic, oxidase-negative, non-motile isolate from the ulcer of a farmed Atlantic salmon (

Topics: Animals; Aquaculture; Arthrobacter; Bacterial Typing Techniques; Base Composition; Cell Wall; Chile; DNA, Bacterial; Fatty Acids; Fish Diseases; Nucleic Acid Hybridization; Peptidoglycan; Phylogeny; RNA, Ribosomal, 16S; Salmo salar; Sequence Analysis, DNA; Ulcer; Vitamin K 2

Three strains, H01100409B

Topics: Animals; Base Composition; DNA, Bacterial; Fish Diseases; Fisheries; Genes, Bacterial; Genome, Bacterial; Phenotype; Photobacterium; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Spain; Species Specificity; Vitamin K 2

A novel Gram-stain-negative, rod-shaped (0.3 × 4-6 μm), non-flagellated, aerobic strain with gliding motility, designated JBKA-6T, was isolated in 1991 from a yellowtail fish, Seriola quinqueradiata, showing symptoms of bacterial haemolytic jaundice. 16S rRNA gene sequence analysis showed that strain JBKA-6T was related most closely to members of the family Flavobacteriaceae in the phylum 'Bacteroidetes'. Furthermore, based on gyrB gene sequence analysis, JBKA-6T was classified into a single clade within the order Flavobacteriales, which was distinct from the known clades of the families Flavobacteriaceae, Blattabacteriaceae and Cryomorphaceae. The predominant isoprenoid quinone was identified as MK-6 (97.9 %), and the major cellular fatty acids (>10 %) were C14 : 0 and iso-C15 : 0. The main polar lipids were phosphatidylethanolamine, three unidentified phospholipids, two unidentified aminophospholipids and two unidentified polar lipids. The DNA G+C content of JBKA-6T, as derived from its whole genome, was 33.4 mol%. The distinct phylogenetic position and phenotypic traits of strain JBKA-6T distinguish it from all other described species of the phylum 'Bacteroidetes', and therefore it was concluded that strain JBKA-6T represents a new member of the phylum 'Bacteroidetes', and the name Ichthyobacterium seriolicida gen. nov., sp. nov. is proposed. The type strain of Ichthyobacterium seriolicida is JBKA-6T ( = ATCC BAA-2465T = JCM 18228T). We also propose that Icthyobacterium gen. nov. is the type genus of a novel family, Ichthyobacteriaceae fam. nov.

Topics: Animals; Bacterial Typing Techniques; Bacteroidetes; Base Composition; DNA, Bacterial; Fatty Acids; Fish Diseases; Jaundice; Perciformes; Phosphatidylethanolamines; Phospholipids; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Vitamin K 2

A taxonomic study was carried out on five Gram-staining-negative, catalase- and oxidase-positive, rod-shaped bacteria isolated from the gills and livers of five diseased rainbow trout. The five novel isolates were designated strains 687B-08(T), 445-08, 452-08, 453B-08 and 967B-08. In phylogenetic analyses based on 16S rRNA gene sequences, the five novel strains appeared almost identical (99.0-100 % sequence similarity) and to belong to the genus Chryseobacterium. Strain 687B-08(T) (the strain selected to represent the five novel isolates) was found to be most closely related to Chryseobacterium oncorhynchi 701B-08(T) (98.9% sequence similarity), Chryseobacterium ureilyticum F-Fue-04IIIaaaa(T) (98.6%), Chryseobacterium indologenes ATCC 29897(T) (98.3%), Chryseobacterium jejuense JS17-8(T) (98.1%) and Chryseobacterium gleum ATCC 35910(T) (98.1%). In DNA-DNA hybridizations, DNA-DNA relatedness values of 99-100% were recorded between the five novel strains. Lower DNA-DNA relatedness values (21-57%) were recorded between strain 687B-08(T) and C. oncorhynchi 701B-08(T), C. ureilyticum F-Fue-04IIIaaaa(T) and the type strains of other closely related, established species of the genus Chryseobacterium. The predominant respiratory quinone of strain 687B-08(T) was MK-6 and the major cellular fatty acids were iso-C(15:0), iso-C(17:1)ω9c, iso-C(17:0) 3-OH and C(16:1)ω6c. The G+C content of the genomic DNA of strain 687B-08(T) was 38.6 mol%. Based on the phenotypic and genotypic evidence, the five novel strains isolated from rainbow trout represent a single, novel species of the genus Chryseobacterium, for which the name Chryseobacterium viscerum sp. nov. is proposed. The type strain is 687B-08(T) ( = CECT 7793(T)  = CCUG 60103(T)).

Topics: Animals; Bacterial Typing Techniques; Base Composition; Chryseobacterium; DNA, Bacterial; Fatty Acids; Fish Diseases; Gills; Liver; Molecular Sequence Data; Nucleic Acid Hybridization; Oncorhynchus mykiss; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Vitamin K 2