Bacillus thuringiensis serovar mogi of a novel serogroup (H3a3b3d), which showed mosquitocidal activity against Anopheles sinensis and Culex pipiens pallens, was isolated from fallen leaves in Mungyeong city, Republic of Korea. In contrast to the complicated plasmid profiles of B. thuringiensis H3 serotype strains, the B. thuringiensis serovar mogi contained only megaplasmid (> 30 MDa) on which the toxin genes were occasionally located. Sequence analysis using 454-pyrosequencing revealed that the megaplasmid harbored at least seven putative cry genes, showing about 84%, 75%, 73%, 58%, 84%, 39% and 75% similarities in amino acid sequences with Cry27Aa, Cry19Ba, Cry20-like, Cry56Aa, Cry39ORF2, Cry8Ba and Cry40ORF2, respectively. These cry genes were cloned to the Escherichia coli-B. thuringiensis shuttle vector, pHT1K, and then introduced into an acrystalliferous B. thuringiensis Cry-B strain for further molecular characterization. To investigate the role of these genes in crystal production, the expression profiles of these toxin genes were analyzed by quantitative real-time PCR (qrtPCR) from the wild type strain as well as transformant strains. The results clearly indicate that the cry39orf2 was the dominant ingredient in the crystal. This novel 3a3b3d type strain, B. thuringiensis serovar mogi, could be used as a good resource for studying unknown mosquitocidal cry genes.

In the transcriptome surveys of Laodelphax striatellus, several cDNA sequences showed a high level of similarities to the insect picorna-like virus genomes. Interestingly, there was no sequence similarity between picorna-like virus sequences from the RSV-viruliferous and those from the non-viruliferous L. striatellus. Picorna-like virus from the non-viruliferous L. striatellus was a geographical isolate of Himetobi P virus (HiPV). The genome of the HiPV was 9,272 nt in length excluding the poly(A) tail and contained two open reading frames (ORFs), which were separated by a 176 nt intergenic region that functions as an internal ribosome entry site (IRES). The 5' ORF encodes the non-structural proteins and the 3' ORF encodes the capsid proteins. The partial genomic RNA of the picorna-like virus from the RSV-viruliferous L. striatellus, LsPV-2, was 8,769 nt in length excluding the poly(A) tail and contained a single, large open reading frame (nt 1–8,535) encoding a 2,845 aa polyprotein. In terms of sequence similarity, identity, and genome organization, LsPV-2 resembled insect picornalike viruses belonging to the family Iflaviridae. A phylogenetic analysis based on RNA-dependent RNA polymerase (RdRp) sequence showed that LsPV-2 was most closely related to the deformed wing virus (DWV). The HiPV and LsPV-2 were incompatible each other in L. striatellus, suggesting that these two picorna-like viruses may have important functions in transmission of the RSV.

Plasmids from Bacillus thuringiensis have been implicated in pathogenicity as they carry the genes responsible for different types of diseases in mammals and insects. B. thuringiensis serovar mogi of a novel serogroup (H3a3b3d), which showed mosquitocidal activity against Anopheles sinensis and Culex pipiens pallens, was isolated from fallen leaves in Mungyeong city, Republic of Korea. In contrast to the complicated plasmid profiles of B. thuringiensis H3 serotype strains, the B. thuringiensis serovar mogi contained only megaplasmid (> 30 MDa) on which the toxin genes were occasionally located. Sequence analysis using 454-pyrosequencing revealed that the megaplasmid harbored at least seven putative cry genes, showing about 84%, 75%, 73%, 58%, 84%, 39% and 75% similarities in amino acid sequences with Cry27Aa, Cry19Ba, Cry20-like, Cry56Aa, Cry39ORF2, Cry8Ba and Cry40ORF2, respectively. These cry genes were cloned to the Escherichia coli-B. thuringiensis shuttle vector, pHT1K, and then introduced into an acrystalliferous B. thuringiensis Cry-B strain for further molecular characterization. This novel 3a3b3d type strain, B. thuringiensis serovar mogi, could be used as a good resource for studying unknown mosquitocidal cry genes.

ORF11 (ac11) of Autographa californica multiple nucleopolyhedrovirus (AcMNPV) is a highly conserved baculovirus gene whose homologs are found in all lepidoteran Group I NPV, but its function is unknown so far. To determine the role of ac11 in baculovirus life cycle, ac11 knock-out mutant, Ac11KO, was constructed using the plasmid capture system (PCS). Real-Time PCR analysis showed that ac11 transcript was first detected at 6 h post-infection (p.i.) and accumulated to maximum at 48 h p.i., indicating that ac11 is belong to late gene. When the genomic DNA of Ac11KO was transfected into Sf9 cells, viral replication was restricted to a cell transfected originally. While viral transmission of the Ac11KO was not observed in Sf9 cells, production of budded virus (BV) in Sf9 cells transfected with Ac11KO was observed by transmission electron microscopy (TEM). These results suggest that the ac11 is essential for AcMNPV to produce infective BV.