The DNA polymerase (DNApol) and major capsid protein (MCP) genes were used as models to study promoter activity in Chilo iridescent virus (CIV). Infection of Bombyx mori SPC-BM-36 cells in the presence of inhibitors of DNA or protein synthesis showed that DNApol, as well as helicase, is an immediate-early gene and confirmed that the major capsid protein (MCP) is a late gene. Transcription of DNApol initiated 35 nt upstream and that of MCP 14 nt upstream of the translational start site. In a luciferase reporter gene assay both promoters were active only when cells were infected with CIV. For DNApol sequences between position -27 and -6, relative to the transcriptional start site, were essential for promoter activity. Furthermore, mutation of a G within the sequence TTGTTTT located just upstream of the DNApol transcription initiation site reduced the promoter activity by 25%. Sequences crucial for MCP promoter activity are located between positions -53 and -29.

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The delayed-early DNA polymerase promoter of Chilo iridescent virus (CIV), officially known as Invertebrate iridescent virus, was fine mapped by constructing a series of increasing deletions and by introducing point mutations. The effects of these mutations were examined in a luciferase reporter gene system using Bombyx mori cells transfected with promoter constructs and infected with CIV. When the size of the upstream element was reduced from position "19 to "15, relative to the transcriptional start site, the luciferase activity was reduced to almost zero. Point mutations showed that each of the 5 nt (AAAAT) located between-19 and-15 were equally essential for promoter activity. Mutations at individual bases around the transcription initiation site showed that the promoter extended until position "2 upstream of the transcription start site. SouthWestern analysis showed that a protein of approximately 100 kDa interacted with the "19 nt promoter fragment in CIV-infected cells. This binding did not occur with a point mutant that lacked promoter activity. The AAAAT motif was also found in the DNA polymerase promoter region of other iridoviruses and in other putative CIV delayed-early genes.

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The chitinase B (chiB) and C (chiC) genes and flanking regions from a local isolate of Serratia marcescens were cloned individually and sequenced. Results showed that these chiB and chiC genes have a 96 % maximum similarity with chiB and chiC from different S. marcescens species (GenBank numbers Z36295.1 and AJ630582.1, respectively). The amplified chiB fragment, including some upstream and downstream regions, is 1,689-bp long with an open reading frame of 1,500 bp. The amplified fragment of chiC is 1,844 bp with an open reading frame of 1,443 bp. These sequences were submitted to the GenBank with accession numbers JX847796 (chiB) and JX847797 (chiC). Putative promoter regions and Shine-Dalgarno sequences were identified in both genes. The genes were cloned into a shuttle vector and the constructs were designated as pHYSB and pHYSC, respectively. Both plasmids were introduced separately into kurstaki and israelensis strains of Bacillus thuringiensis and the insecticidal activities of the engineered B. thuringiensis strains were assayed in larvae of Galleria mellonella and adult of Drosophila melanogaster. Engineered B. thuringiensis strains showed higher insecticidal activity than parental strain and the parental S. marcescens. In addition, pHYSB and pHYSC were stable over 16 daily passages under non-selective conditions in transformed B. t. israelensis 5724 strain.

In this study, the bacterial flora of Hyphantria cunea Drury. (Lep., Arctiidae) were investigated during three hazelnut seasons from 1998 to 2000. Four different bacteria were found in dead and living larvae. They were isolated and identified as Bacillus thuringiensis, Escherichia freundii, Micrococcus sp. and Streptococcus sp. Laboratory experiments carried out to determine the insecticidal activities of these isolates showed that E. freundii and Micrococcus sp. did not have any insecticidal effect on second – third instar larvae of H. cunea. However, B. thuringiensis and Streptococcus sp. had 56 and 38% effects, respectively. Crystals and spores from B. thuringiensis were also purified and the crystals, spores and crystals–spore mixture were tested separately against the larvae of H. cunea. It was found that the insecticidal activities of the crystals, spores and crystal–spore mixture were 37.5, 25 and 62.5%, respectively, on second – third instar larvae of H. cunea. These results indicate that the crystal–spore mixture has 6.5% more insecticidal effect than that of the vegetative cells of the B. thuringiensis isolate.

IntroductionBaculoviruses are enveloped viruses that have doublestranded, circular DNA genomes ranging in size from 80 to 180 kbp (1,2). Baculoviruses have been isolated from more than 600 insect species belonging to the orders of Lepidoptera, Hymenoptera, Diptera, Orthoptera, Coleoptera, Neuroptera, Thysanura, and Trichoptera (3). The most notable characteristic of baculoviruses is the occlusion body (OB). The occlusion body is a crystalline matrix composed of a protein called polyhedrin, which provides protection to the virions in the environment against proteolytic and chitinolytic enzymes in the decomposing larvae and spreads infection among insects (4,5). Baculoviruses have been taxonomically divided based on their OB morphology into nucleopolyhedroviruses (NPVs) and granuloviruses (GVs), forming polyhedra and granula, respectively (6). In the NPV, the OB ranges in size from 0.4 to 5 µm in diameter and contains several virions (7,8). The OBs of NPVs are most easily seen under light microscope due to their larger size and their light refractory polyhedral structure. The OBs of GVs, called granula, appear as dark granules and are comparatively more difficult to resolve under light microscope. They are ovoid-shaped and about 500 nm long and 20 nm wide (8,9).The family Baculoviridae is divided into 4 genera according to common biological and structural characteristics and patterns of host associations: Alphabaculovirus, which includes lepidopteran-specific baculoviruses and is subdivided into Group I or Group II based on the phylogenetic analysis of the polyhedrin genes from different baculoviruses; Betabaculovirus, comprising lepidopteran-specific granuloviruses; Gammabaculovirus, which includes hymenopteran-specific baculoviruses; and finally Deltabaculovirus, which contains dipteran-specific baculoviruses (4,10,11).Malacosoma neustria (Linnaeus, 1758) (Lepidoptera: Lasiocampidae), known as the European tent caterpillar, is an important defoliator of various fruit trees such as apple, pear, and plum; wild and ornamental trees and shrubs, including oak and rose species, oleaster, sea buckthorn, barberry, elm trees, willow, poplar, and aspen; and birch, particularly in eastern and central Turkey (12)(13)(14). The caterpillars first eat the buds and then leaves of the trees. During some years their population reaches such high numbers that they leave the trees completely leafless. Factors such as weather conditions and natural enemies including predators, parasitoids, and pathogenic microorganisms have historically been important regulatory elements in the population cycles of this insect.The key microbial pathogens of this insect include NPVs (15). The presence of NPVs in M. neustria was reported by several authors (16-31). In 2009, Demir et al.

Thaumetopoea pityocampa (pine processionary moth) is one of the most important pine pests in the forests of Mediterranean countries, Central Europe, the Middle East and North Africa. Apart from causing significant damage to pinewoods, T. pityocampa occurrence is also an issue for public and animal health, as it is responsible for dermatological reactions in humans and animals by contact with its irritating hairs. High throughput sequencing technologies have allowed the fast and cost-effective generation of genetic information of interest to understand different biological aspects of non-model organisms as well as the identification of potential pathogens. Using these technologies, we have obtained and characterized the transcriptome of T. pityocampa larvae collected in 12 different geographical locations in Turkey. cDNA libraries for Illumina sequencing were prepared from four larval tissues, head, gut, fat body and integument. By pooling the sequences from Illumina platform with those previously published using the Roche 454-FLX and Sanger methods we generated the largest reference transcriptome of T. pityocampa. In addition, this study has also allowed identification of possible viral pathogens with potential application in future biocontrol strategies.