Keywords: Quinolones; Virulence genes; UTI

The aim of this study was to identify antimicrobial resistance and virulence factor genes exhibited by multidrug resistant (MDR)Acinetobacter baumannii, to analyze biofilm formation and to investigate clonal subtypes of isolate. Whole genome sequencing was done by Illumina NovaSeq 6,000 platform and multilocus sequence typing (MLST) was performed by Oxford and Pasteur typing schemes. Influence of imipenem and levofloxacin on biofilm formation was investigated in 96-well plates at 3 replicates. The strain was found to carry OXA-23, OXA-51-like, AmpC and TEM-1 beta-lactamases. The sequence of thebla_OXA-51-likegene has been identified as abla_OXA-66. According to Pasteur MLST scheme the strain displayed ST2 allelic profile. However, based on Oxford MLST scheme this strain represents the new ST2121, as thegdhBgene has a single allelic mutation namely, thegdhB-227. It was determined that MDR isolate carriedbap, basABCDFGHIJ, csuA/BABCDE, bauABCDEF, plcD, pgaABCD, entE, barAB, ompA, abaIR, piT2EAFTE/AUBl, fimADT, cvaC, bfmR, bfmSvirulence genes. In our study imipenem induced the highest biofilm formation at a concentration of 32 µg/ml and levofloxacin at a concentration of 16 µg/ml. In conclusion, we detected a new MDRA. baumanniiST2121 clone harboringbla_OXA-66gene that has been reported for the first time in Turkey.

The object of the present study was to investigate the antioxidant, antimicrobial activity and phenolic compounds of fruit and seeds of Diospyros lotus L. The fruits consumed by humans as nutrients were harvested from the plants that grow naturally in the province of Trabzon-Akçaabat, Eastern Black Sea Region of Turkey. The antioxidant activities of fruit and seeds of Diospyros lotus were determined by using four methods (% DPPH radical scavenging activity, FRAP antioxidant power determination, CUPRAC reducing antioxidant activity and total phenolic content (TPC) in five different proportion of methanol-water extracts. All extracts of fruit and seeds of D. lotus analyzed through whole antioxidant analysis methods showed significant antioxidant activity. In addition, antimicrobial activity of fruit and seeds extracted with DMSO was determined against seven standard bacteria and three multi-drug resistance clinical strains. Although fruit extracts did not have the antimicrobial activity against bacteria, seeds showed antimicrobial effect to both standard strains (Gram-negative and Gram-positive) and antibiotic resistance clinical isolates (Klebsiella pneumoniae carrying blaKPC, Acinetobacter baumannii, harboring blaOXA-23 gene and resistance to colistin, and multi-drug resistant Pseudomonas aeruginosa). MICs’ value of plant seed extracts for standard strains was 0.75-25 mg/mL and antibiotic resistant clinical bacteria were 12.5 and 25 mg/mL. Additionally, phenolic compounds in methanol extracts of fruit and seeds were also determined in by HPLC using 19 standards. Gallic acid and chrysin phenolic compounds were the major phenolic compounds in fruit and seeds, respectively.

Aim: The aim of this study was to identify antimicrobial resistance genes, virulence factor genes, and porin loss or mutations exhibited by the multidrug-resistant Klebsiella pneumoniae strain. Materials and Methods: Whole-genome sequencing was done via the Illumina NovaSeq 6000 platform. Strain identification and antibiotic susceptibility testing of strains were performed by the Vitek 2 automated system. Multilocus sequence typing analysis was carried out using seven conserved housekeeping genes. Results: The strain was resistant to penicillins, cephalosporins, carbapenems, aminoglycosides, fluoroquinolones, fosfomycin, and trimethoprim/sulfamethoxazole. The isolate was found to carry KPC-3, CTX-M-27, SHV-11, SHV-67, and TEM-1 β-lactamases. The clonal subtype of the isolate was ST147, and it possessed wzi 64 and wzc 38 alleles. Fifteen different point mutations (N49S, L59V, R146H, V178P, G189T, F198Y, V202L, F207Y, A217S, T222L, D223G, H235N, A280V, N304E, and S346N) were detected in the OmpK36 porin. A frame shift was observed in OmpK35 and two different point mutations (I70M and I128M) were found in the OmpK37 porin, in addition to seven mutations observed on the AcrR. Conclusions: This study demonstrated for the first time that the ST147 clone produced CTX-M-27 as well as KPC-3. In addition, new mutations were detected in the outer membrane proteins. These mutations together with the production of extended-spectrum β-lactamase and carbapenemase were found to contribute to the resistance of the ST147 clone to carbapenem and other antibiotics.

This study investigated the total phenolic and flavonoid contents and the antioxidant, antimicrobial, antibiofilm and α-glucosidase inhibitory activities of methanol extract from Vaccinium arctostaphylos L. leaf and fruit parts. The highest antioxidant activity with 53 µM TEAC and 0.0084 mg/mL SC50 using the ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays, respectively determined in leaf part. The data indicated that the leaf of the plant had the higher total phenolic content (49 µg/mL GAE) and total flavonoid content (0.071 µg/mL QAE) compared to fruit. The α-glucosidase enzyme activity of the leaves (0.179 mg/mL IC₅₀) was observed to be higher than that of the fruits (0.386 mg/mL IC₅₀). The MIC values of the leaf and fruit parts of blueberry were 6.25 mg/ml and 3.125 mg/ml, respectively. The results of this study indicate that the leaf extract was found to significantly reduce the biofilm-forming capacity of the Acinetobacter baumannii isolate by approximately 3-fold, whereas the fruit extract was observed to have only a marginal effect, reducing the biofilm-forming capacity by approximately 1.4-fold. The effects of plant extracts on microbial biofilms may be examined with a view to combating antibiotic resistance. Also results suggesting that it might be an effective and safety medical plant to prevent or treat diseases associated with oxidative damage and bacterial infections. Consequently, further research on natural substances may lead to the development of treatment options.