Viral nervous necrosis (VNN) is a worldwide disease among marine fishes. In Taiwan, NNN disease was first identified in 2 species of hatchery-reared grouper, Epinephelus fuscogutatus and E. akaaya in 1994. Since then, increasing mortalities have occurred among groupers Epinephelus spp., and also among European eels Anguilla anguilla L., yellow-wax pompano Trachinotus falcatus, firespot snapper Lutaanus erythropterus B., barramundi Lates calcarifer, cobias Rachycentron canadum, humpback groupers Cromileptes altivelis and Chinese catfish Parasilurus asotus. In the present study, samples were collected from affected fishes and processed for reverse transcriptase (RT) PCR amplification and virus isolation in cell culture. Infected cells (GF-1 cell line) exhibited cytopathic-effect characteristics of grouper nervous necrosis virus (GNNV). A RT-PCR product of approximately 830 bp was amplified from the brain homogenate of tested samples and sequenced. The nucleotide and deduced amino acid sequences of the amplified RT-PCR products from all isolates were strongly homologous (> 97%) with the corresponding region of the published sequence of redspotted grouper nervous necrosis virus (RGNVV). Therefore, all Taiwan NNV (nervous necrosis virus) isolates studied in this report belong to the RGNNV genotype. We used 5 neutralizing monoclonal antibodies (MAbs) against GNNV to analyze the antigenic relationship of Taiwan NNV isolates and striped jack nervous necrosis virus (SJNNV). The results of neutralization tests revealed that all Taiwan NNV isolates were closely related, but antigenically different from SJNNV in 3 neutralizing epitopes. To our knowledge, this is the first description of NNV infection in European eels, yellow-wax pompano, firespot snapper, cobia and Chinese catfish, and the first reported instance of natural NNV infection in freshwater fishes causing high mortality. KEY WORDS: Fish nodavirus · Betanodavirus · Nervous necrosis virus · NNV · Monoclonal antibody · Neutralizing epitopeResale or republication not permitted without written consent of the publisher

Five Gram-stain-positive strains (M1-10T, M1-13, M1-21T, M2-14T and S1-1T) were isolated from paper mulberry (Broussonetia papyrifera) in Taiwan. Cells were rod-shaped, non-motile, non-haemolytic, asporogenous, facultatively anaerobic, heterofermentative, and did not exhibit catalase and oxidase activities. Phylogenetic analysis of the 16S rRNA gene sequences revealed that these novel strains belonged to the genus Fructobacillus . On the basis of 16S rRNA gene sequence similarities, the type strains of Fructobacillus fructosus and Fructobacillus durionis were the closest neighbours to strains M1-10T, M1-13, M1-21T, M2-14T and S1-1T. Sequence analyses of concatenated two partial housekeeping genes, the RNA polymerase beta subunit (rpoC) and recombinase A (recA) also indicated that the novel strains belonged to the genus Fructobacillus . The 16S rRNA and concatenated rpoC and recA gene sequence similarities between strains M1-10T and M1-13 were 100 %, respectively. The average nucleotide identity values of M1-10T, M1-21T, M2-14T and S1-1T with F. fructosus and F. durionis were 75.1–78.9% and 76.5–77.5 %, respectively. The digital DNA–DNA hybridization values were 19.7–21.5% and 19.6–20.4 %, respectively. Phenotypic and genotypic test results demonstrated that these strains represent four novel species of the genus Fructobacillus , for which the names Fructobacillus papyriferae sp. nov., Fructobacillus papyrifericola sp. nov., Fructobacillus broussonetiae sp. nov. and Fructobacillus parabroussonetiae sp. nov. are proposed with the type strains M1-10T (=BCRC 81237T=NBRC 114433T), M1-21T (=BCRC 81239T=NBRC 114435T), M2-14T (=BCRC 81240T=NBRC 114436T) and S1-1T (=BCRC 81241T=NBRC 114437T), respectively.

Four Gram-stain-positive strains, R7T, R11, R19T and R27, were isolated from suan-tsai, a traditional fermented mustard green product of Taiwan. Cells were rod-shaped, non-motile, non-haemolytic, asporogenous, facultatively anaerobic, heterofermentative, and did not exhibit catalase and oxidase activities. Comparative analyses of 16S rRNA, pheS and rpoA gene sequences demonstrated that these novel strains were members of the genus Lactobacillus . 16S rRNA and the concatenated pheS and rpoA gene sequence similarities between strains R7T and R11, and strains R19T and R27 were very high (>99.8 % similarity), respectively. On the basis of 16S rRNA gene sequence similarities, the type strains of Lactobacillus paralimentarius (98.5 %), Lactobacillus kimchii (98.5 %), Lactobacillus alimentarius (98.1 %) and Lactobacillus bobalius (98.1 %) were the closest neighbours to strains R7T and R11, and the type strains of Lactobacillus brevis (98.9 %), Lactobacillus cerevisiae (98.4 %), Lactobacillus hammesii (98.4 %), Lactobacillus koreensis (98.4 %) and Lactobacillus yonginensis (98.0 %) were the closest neighbours to strains R19T and R27, respectively. The average nucleotide identity values of R7T and R19T with the closely related type strains were 78.9–80.1% and 75.7–80.5 %, respectively. The digital DNA–DNA hybridization values were 22.8–23.6% and 21.0–23.1 %, respectively. Phenotypic and genotypic test results demonstrated that these strains represent two novel species of the genus Lactobacillus , for which the name Lactobacillus suantsaicola sp. nov. (R7T=BCRC 81127T=NBRC 113530T) and Lactobacillus suantsaiihabitans sp. nov. (R19T=BCRC 81129T=NBRC 113532T) are proposed.

A Gram-stain-positive strain, 8 H-2T, was isolated from faeces of Reeves’ muntjac (Muntiacus reevesi) barking deer in Taiwan. Cells of the strain were short rod-shaped, non-motile, non-haemolytic, asporogenous, facultatively anaerobic, heterofermentative and did not exhibit catalase and oxidase activities. Comparative analyses of 16S rRNA, pheS and dnaA gene sequences demonstrated that the novel strain was a member of the genus Weissella . On the basis of 16S rRNA gene sequence similarities, the type strains of Weissella oryzae (99.2 %), Weissella confusa (97.8 %), Weissella cibaria (97.6 %) and Weissella soli (97.3 %) were the closest neighbours to strain 8 H-2T. The concatenated housekeeping gene sequence (pheS and dnaA) similarities of 8 H-2T to closely related type strains were 72.5–84.9 %, respectively. The genomic DNA G+C content was 40.5 mol%. The average nucleotide identity and digital DNA–DNA hybridization values with these type strains were 70.2–75.4% and 25.1–30.1 %, respectively. Phenotypic and genotypic test results demonstrated that strain 8 H-2T represents a novel species belonging to the genus Weissella , for which the name Weissella muntiaci sp. nov. is proposed. The type strain is 8 H-2T (=BCRC 81133T=NBRC 113537T).

No abstract