Entomopathogenic fungi (EPFs) play an important role for regulating insect pest populations, as they exist in many different ecosystems. Within these fungi, Beauveria and Metarhizium spp. genera include species that are the most commercially important. The aim of this study was to determine the diversity and distribution of Beauveria and Metarhizium spp. in walnut fields of Kırşehir, Turkey, and to evaluate their pathogenicity against Cydia pomonella (L.) (Lepidoptera: Tortricidae). To perform this, 90 soil samples were collected from walnut fields where Beauveria and Metarhizium spp. were isolated from these soils, using selective media. The isolated 40 fungi were characterized based on their morphological and molecular characteristics including Bloc and β-tubulin gene sequences. Also, eight selected fungi were tested against C. pomonella larvae under laboratory conditions. The fungal isolates were identified as Beauveria pseudobassiana (15), B. bassiana (12), Metarhizium robertsii (11), and M. brunneum (13). M. brunneum ELA-38 caused 83% mortality within 2 weeks after application of 1 × 108 conidia/ml. Consequently, Beauveria and Metarhizium spp. are the common component of the soils collected from walnut fields and some of fungi obtained from this work might be beneficial in the future biological control programs of C. pomonella.

Background: This study aimed to evaluate antibiotic resistance genes and virulence genes and the clonal relationship of the carbapenem-nonsusceptible Klebsiella pneumoniae strains by molecular methods which are isolated from various clinical specimens from patients treated in tertiary care hospital in Turkey. Methods: Identification of 32 carbapenem non-susceptible K. pneumoniae were determined by VITEK-2 (BioMérieux, France) automated system. Thirteen colistin-resistant strains were tested with the broth microdilution method. Various antibiotic resistance genes and virulence genes frequently seen in carbapenem-resistant strains were screened by PCR. Immunochromatographic tests used in the rapid diagnosis of carbapenemases were compared with PCR results. In addition, PFGE, MLST and MALDI-TOF MS methods were used to determine the clonal relationship among these strains. Results: PCR demonstrated that 31 of the strains carried at least one of the carbapenemase genes. In one strain, the coexistence of bla_OXA−48+NDM was shown. The most common resistance genes were determined as bla_SHV (84.3%), bla_CTX−M−1 (46.8%), bla_OXA−48 (40.6%), bla_KPC (40.6%), bla_TEM (31.2%), bla_NDM (18.8%) respectively. Among the virulence genes; magA (68.7%) was the most common, followed by kpn (59.3%) and K2 (9.3%). Immunochromatographic tests were found to be 100% compatible with PCR results. All colistin-resistant isolates were also found to be resistant by colistin broth microdilution. In PFGE analysis, 25 different genotypes were determined and clustering isolates were collected in 5 different clusters and the clustering rate was 35.4%. In MLST analysis, ST101 type was determined as the most common ST type with a rate of 29%. ST101 is followed by ST16, ST307, ST14, ST147, ST309, ST377, ST395 and ST2096, respectively. The compatibility rate between MALDI-TOF MS and VITEK-2 was found 94.3%, in bacterial identification. In MALDI-TOF MS typing, the maximum similarity between the strains was less than 70% and clustering not shown. Conclusion: In addition to OXA-48, which is endemic in our country, it has been determined that KPC, which is more common in the world, is becoming increasingly common in our region. ST101 type was determined as the most common type between the strains. To the best of our knowledge, this is the first study that compares these three methods in our country. There may be differences between bacterial identifications made with VITEK-2 and MALDI-TOF MS. In this study, it was observed that MALDI-TOF MS analyses were not compatible with the typing of strains according to PFGE and MLST analysis results.

Paenibacillus larvae (P. larvae) is a pathogenic bacterium causing American Foulbrood Disease (AFB) in honeybee larvae. It is necessary to develop alternative strategies for the control of this disease due to the serious honeybee colonies loses and the use of antibiotics. Recent studies are aimed at the investigating natural fighting agents against P. larvae. In our study, it was aimed to demonstrate potential antibacterial efficacy of ethanol extract of Anatolian Propolis (EAP) against P. larvae strains PB35 and SV35 which were isolated in Turkey. The total phenolic content (TPC) and flavonoid content (TFC) of EEAP were determined as 181.73±5.20 mg Gallic Acid Equivalents (GAE)/g, and 42.33±1.40 mg Quercetin Equivalents (QE)/g, respectively. It was found that EAP contains different amounts of ferulic, caffeic, coumaric acids, rutin, and caffeic acid phenethyl ester (CAPE). The antibacterial activity of the EAP was determined by using agar-well diffusion, microdilution, and Bioscreen C techniques. The Minimal Inhibition Concentration (MIC) values of the EAP were determined as 74.87 μg/ml against strain PB35 and SV35 using both microdilution and Bioscreen C teqnique. In both techniques, Minimal Bactericidal Concentration (MBC) values of the EAP were evaluated as 149 and 598.4 μg/ml against strain PB35 and SV35, respectively. The fact that EAP shows low concentrations of bacteriostatic (MIC) and bactericide (MBC) activity values against P. larvae strains, spore-forming bacilli, which are agents of AFB disease, suggests that it may be a potential source in AFB disease control.

Objective: Staphylococcus aureus is a significant pathogen microorganism that can lead to serious infections. In this study, we researched the activity of biofilm formation and fosfomycin on biofilm in community-acquired S. aureus isolates that were drawn from human noses. Methods: Microtitration plate method was used to determine biofilm formation. The effect of fosfomycin on sessile cells was studied on biofilm matrix composed around plastic beads. The icaA, icaD, icaB, icaC, bap, eno, fnbA, fnbB, clfA, clfB, fib, ebpS, cna and mecA genes were screened by Polymerase Chain Reactions (PCR). Results: S. aureus was isolated from 87 samples (13.2%) out of a total 658 nasal samples. We found that 10 of these isolates (11.4%) were methicillin-resistant S. aureus (MRSA). A total of 86 isolates had the ability to form biofilm. The biofilm inhibitor concentration (BIC) and minimum biofilm eradication concentration (MBEC) of fosfomycin were determined as 8 µg/ml and 32 µg/ml, respectively. In the molecular detection results of biofilm-related genes of these isolates, ica-dependent genes were determined to be quite high. However, no bap gene was observed to be positive in any of the isolates. Among the other genes, the most frequent genes to be declared positive were eno (97.6%) and fnbA (94.1%). Conclusion: This study indicates that prevalence of biofilm genes in S. aureus isolates in nasal flora is high and fosfomycin is an effective anti-biofilm agent alone. However, to increase fosfomycin’s efficiency, there is a need for more combination studies to make it more effective.

Klebsiella pneumoniae ventilatör ilişkili pnömoni (VİP) ile ilişkili enfeksiyonlarda en sık rastlanan etkenlerden biridir. Çok ilaca dirençli (ÇİD) K.pneumoniae izolatları, sağlık hizmeti ile ilişkili enfeksiyonların tedavisinde karşılaşılan en önemli problemlerden birini oluşturmaktadır. K.pneumoniae gibi enfeksiyon etkenlerinin yayılımında, integronlar başta olmak üzere mobil genetik elemanlar önemli bir rol oynamaktadır. Bu çalışmada, VİP etkeni olan K.pneumoniae izolatlarında sınıf 1 ve sınıf 2 integron gen kasetlerinin varlığının belirlenmesi amaçlanmıştır. Çalışma kapsamında, 2022-2023 yılları arasında Kırşehir Eğitim ve Araştırma Hastanesi Yoğun Bakım Ünitesinde VİP hastalarından 22 K.pneumoniae izolatı elde edilmiştir. İzolatların sınıf 1 ve sınıf 2 integron gen kasetlerine spesifik primerler kullanılarak polimeraz zincir reaksiyonu yöntemiyle integronlar saptanmış ve DNA dizi analizleri gerçekleştirilmiştir. Elde edilen diziler GenBank NCBI Blast veri tabanında bulunan diğer diziler ile karşılaştırılarak integron gen kaseti içerikleri belirlenmiştir. İzole edilen 22 K.pneumoniae izolatının beşinde (%22.7) sınıf 1, ikisinde (%9.1) sınıf 2 integron gen kaseti tespit edilmiştir. Sınıf 1 integronların içerdiği direnç genleri arasında trimetoprim direncinden sorumlu dfrA12 ve aminoglikozid grubu antibiyotiklere direnç sağlayan aadA belirlenmiştir. Sınıf 2 integronlarında ise sırasıyla trimetoprim, streptotrisin ve streptomisin/spektinomisine direnç sağlayan dfrA1, sat2 ve aadA1 belirlenmiştir. Çalışmada elde edilen sonuçlar, hastane kökenli ÇİD K.pneumoniae izolatlarının yayılımında integronların önemli bir rol oynadığını ortaya koymaktadır. Hastanelerde görülen antibiyotik dirençli izolatların kontrol altına alınabilmesi için enfeksiyon kontrol önlemlerinin sıkılaştırılması ve antibiyotik direnç mekanizmalarının izlenmesi büyük önem taşımaktadır. Bu çalışma, VİP etkeni K.pneumoniae izolatlarının genetik yapılarını anlamaya, uygun tedavi yaklaşımlarının belirlenmesine ve hastane enfeksiyonlarının kontrolüne katkı sağlayacaktır.