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T. Nishizawa

Publications and source records attributed to T. Nishizawa.

7 recordsLinked to original sources

Genotyping of Korean isolates of infectious hematopoietic necrosis virus (IHNV) based on the glycoprotein gene

Glycoprotein (G) gene nucleotide sequences of four Korean isolates of infectious hematopoietic necrosis virus (IHNV) were analyzed to evaluate their genetic relatedness to worldwide isolates. All Korean isolates were closely related to Japanese isolates of genogroup JRt rather than to those of North American and European genogroups. It is believed that Korean IHNV has been most likely introduced from Japan to Korea by the movement of contaminated fish eggs. Among the Korean isolates, phylogenetically distinct virus types were obtained from sites north and south of a large mountain range, suggesting the possibility of more than one introduction of virus from Japan. ?? 2007 Springer-Verlag.

Archives of Virology↗

Sequence analysis and expression of the M1 and M2 matrix protein genes of hirame rhabdovirus (HIRRV)

We have cloned and sequenced a 2318 nucleotide region of the genomic RNA of hirame rhabdovirus (HIRRV), an important viral pathogen of Japanese flounder Paralichthys olivaceus. This region comprises approximately two-thirds of the 3' end of the nucleocapsid protein (N) gene and the complete matrix protein (M1 and M2) genes with the associated intergenic regions. The partial N gene sequence was 812 nucleotides in length with an open reading frame (ORF) that encoded the carboxyl-terminal 250 amino acids of the N protein. The M1 and M2 genes were 771 and 700 nucleotides in length, respectively, with ORFs encoding proteins of 227 and 193 amino acids. The M1 gene sequence contained an additional small ORF that could encode a highly basic, arginine-rich protein of 25 amino acids. Comparisons of the N, M1, and M2 gene sequences of HIRRV with the corresponding sequences of the fish rhabdoviruses, infectious hematopoietic necrosis virus (IHNV) or viral hemorrhagic septicemia virus (VHSV) indicated that HIRRV was more closely related to IHNV than to VHSV, but was clearly distinct from either. The putative consensus gene termination sequence for IHNV and VHSV, AGAYAG(A)(7), was present in the N-M1, M1-M2, and M2-G intergenic regions of HIRRV as were the putative transcription initiation sequences YGGCAC and AACA. An Escherichia coli expression system was used to produce recombinant proteins from the M1 and M2 genes of HIRRV. These were the same size as the authentic M1 and M2 proteins and reacted with anti-HIRRV rabbit serum in western blots. These reagents can be used for further study of the fish immune response and to test novel control methods.

Diseases of Aquatic Organisms↗

Kinetics and mechanisms of iron sulfide reductions in hydrogen and in carbon monoxide

The reduction of iron sulfides by hydrogen and by carbon monoxide has been studied using plug flow and thermogravimetric methods. The reactions were studied in the 523–723°K temperature range and were found to be first-order processes. Plug flow studies were used to correlate reaction rates between pyrite and the gases as a function of the surface area of the pyrite. The rate of H 2 S formation increases with the surface area of the pyrite sample. The results of thermogravimetric experiments indicate that the reactions consist of several steps. Rate constants for the pyrite reduction by H 2 and by CO were obtained. The activation energies increased with degree of reduction. Values of E a were 113.2 (step I) and 122.5 kJ/mole (step II) for pyrite reduction with CO and 99.4 (step I), 122.4 (step II), 125.2 (step III), and 142.6 kJ/mole (step IV) for pyrite reduction with hydrogen.

Journal of Solid State Chemistry↗