Seven closely related xylanolytic, thermophilic bacilli were isolated from mud and water samples from the Gonen and Diyadin hot springs, respectively located in the Turkish provinces of Balikesir and Agri. On the basis of morphology and biochemical characteristics, one of the isolates, designated strain G2 T , was studied further. Strain G2 T is a xylanolytic, sporulating, Grampositive, rod-shaped bacterium. The isolate is a thermophilic (optimum temperature for growth, 55-60˚C), facultative anaerobe that grows on a wide range of carbon sources, including glucose, starch, xylose and mannitol. It expressed a high level of xylose isomerase activity on xylose and also on glucose. 16S rRNA gene sequence analysis showed that this isolate resembled Anoxybacillus flavithermus DSM 2641 T (>97 % similarity), but 16S-23S rDNA internally transcribed spacer polymorphism PCR showed variation between DSM 2641 T and isolate G2 T . However, it is also known that analysis of 16S rRNA gene sequences may be insufficient to distinguish between some species. In DNA-DNA hybridization, thermophilic isolate G2 T showed relatedness of 53?4 % to A. flavithermus and about 45?0 % to Anoxybacillus pushchinoensis, indicating that it is distinct at the species level. On the basis of the evidence presented, it is proposed that strain G2 T (=NCIMB 13933 T =NCCB 100040 T ) be designated as the type strain of Anoxybacillus gonensis sp. nov.It is now over a century since thermophiles were first reported (Miquel, 1888). Over the years, a number of sporeforming thermophiles have been reported, mainly in the genera Bacillus and Clostridium (Guagliardi et al., 1996).In this study, we isolated some thermophilic bacilli from the Gonen and Diyadin hot springs, respectively located in the Turkish provinces of Balikesir and Agri. On the basis of preliminary experiments, a representative strain appeared to differ from other thermophilic bacilli with respect to the utilization of xylose; it was therefore characterized further. Xylose isomerase is an intracellular enzyme that catalyses the conversion of D-xylose to D-xylulose. Its practical significance stems from its ability to isomerize D-glucose to D-fructose. Therefore, this enzyme is often referred to as glucose isomerase and is widely used in industry for the production of high-fructose corn syrup.The present paper describes the isolation, morphological, physiological and biochemical profiles and 16S rRNA sequence of this strain and the results of DNA-DNA hybridization with close relatives and proposes that it represents a novel species of the genus Anoxybacillus (Pikuta et al., 2000), Anoxybacillus gonensis sp. nov. Isolation of strainsSeven Gram-positive rods were isolated from mud and water samples from the Gonen and Diyadin hot springs. The water temperature of these hot springs is around 70 uC. After collection, mud and water samples were used immediately for enrichment in nutrient broth at 60-70 uC. Oneday-old enrichment cultures were repeatedly subcultured in 10 ml nutrient broth and streaked on ...

Although Turkey is the first among all hazelnut-producing countries, yield per unit area of this crop is low in comparison to other countries, mainly because many insect species seriously damage hazelnut trees and their fruit. To find effective and safe biocontrol agents, we conducted a survey study to isolate entomopathogenic fungi from the hazelnut-growing region of Turkey and characterized the isolated strains in detail. In addition, we determined the effectiveness of seven selected strains from this region against Melolontha melolontha (Coleoptera: Scarabaeidae) which is one of the most serious pests of hazelnut. In 2006 and 2007, 301 soil samples were collected randomly and analyzed for presence of entomopathogenic fungi using the Galleria bait method. Entomopathogenic fungi were found to occur in 20.59% of the soil samples studied. Based on morphology, ITS sequence and partial sequencing of the 18S (SSU rDNA) and EF1-alpha genes, the isolates were identified as Metarhizium anisopliae var. anisopliae, Metarhizium sp., Beauveria bassiana, Beauveria cf. bassiana, Isaria fumosorosea and Evlachovaea sp. Metarhizium anisopliae var. anisopliae was isolated from 34 sites and was the most frequent and abundant entomopathogenic species recovered. All the isolates tested were pathogenic to M. melolontha. M. anisopliae var. anisopliae KTU-27 and Evlachovaea sp. KTU-36 produced the highest insecticidal activity (86.6%) within 15 days after inoculation. Our results suggest that entomopathogenic fungi could be good biocontrol agents against M. melolontha, and are discussed with respect to ecology of fungi in relation to habitat in order to evaluate biocontrol potential of these isolates. This is the first study of the distribution of entomopathogenic fungi in the hazelnut-growing region of Turkey and of their pathogenicities against M. melolonth

Two thermophilic bacilli were isolated from mud and water samples of the Ayder and Kestanbol hot springs in the provinces of Rize and Canakkale, respectively, in Turkey. Strains AB04 T and K4 T were sporulating, Gram-positive, rod-shaped bacteria. These isolates were moderately

Hydrophobins are small, cysteine-rich, secreted proteins, ubiquitously produced by filamentous fungi that are speculated to function in fungal growth, cell surface properties, and development, although this has been rigorously tested for only a few species. Herein, we report identification of three hydrophobin genes from the entomopathogenic fungus, Metarhizium brunneum, and functional characterization of strains lacking these genes. One gene (HYD1/ssgA) encodes a class I hydrophobin identified previously. Two new genes, HYD3 and HYD2, encode a class I and class II hydrophobin, respectively. To examine function, we deleted all three separately, from the M. brunneum strain KTU-60 genome, using Agrobacterium tumefaciens-mediated transformation. Deletion strains were screened for alterations in developmental phenotypes including growth, sporulation, pigmentation, colony surface properties, and virulence to insects. All deletion strains were reduced in their ability to sporulate and showed alterations in wild-type pigmentation, but all retained wild-type hydrophobicity, except for one individual hyd3 mutant. Complementation with the wild-type HYD3 gene restored hydrophobicity. Each gene, present as a single copy in the genome, showed differential expression patterns dependent on the developmental stage of the fungus. When Spodoptera exigua (beet armyworm) larvae were treated with either conidia or blastospores of each hyd mutant, reductions in virulence and delayed mortality were observed as compared to WT. Together, these results suggest that hydrophobins are differentially expressed and may have distinct, but compensating roles, in conidiation, pigmentation, hydrophobicity, and virulence.

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The pine processionary moth Thaumetopoea pityocampa (Den. & Schiff.) is one of the most harmful pests to pine species in Mediterranean countries including Turkey. Caterpillars of T. pityocampa are not only significantly harmful to forest trees but also responsible for various allergic reactions in humans and animals. In this study, in order to find a more effective and safe biological control agent against T. pityocampa, we investigated fungal pathogens of T. pityocampa in the Black Sea Region of Turkey and tested their pathogenicity on it. Five different fungi were isolated and identified based on their morphological and molecular characteristics including ITS and partial sequence of EF1-[alpha]. Based on these characteristics, four isolates were identified as Beauveria bassiana cf. Clade C (Rehner and Buckley in Mycologia 97:84-98, 2005) and one isolate was identified as Beauveria bassiana. Among these isolates, B. bassiana KTU-24, B. bassiana cf. Clade C KTU-66 and KTU-67 showed the highest virulence with 100% mortality within 10 days after application. B. bassiana isolate KTU-24 produced the highest mycosis value with %100. Consequently, B. bassiana KTU-24 seems to be good candidate for further investigation as a possible biological control agent against this pest.

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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.