Isolation of Bacteriophage and Assessment of its Activity against Biofilms of Uropathogenic Escherichia coli in Jimma Town, South Western Ethiopia

Escherichia coli is one of the most commonly associated bacteria with urinary tract infections (UTIs) in humans and many times are antimicrobial resistant. Production of biofilms further makes matters worse in UTIs. Alternative therapy using bacteriophages was known in the past. This study was aimed to isolate lytic bacteriophages from sewage samples and assess their activity against biofilm of uropathogenic E. coli (UPEC). Lytic phage was isolated from sewage water collected in Jimma town following standard enrichment method against UPEC. E. coli was isolated from UTI suspect patients using standard protocol. Microtiter plate technique was used to determine bacterial biofilm formation. Biofilm degrading efficacy of phage was assessed by treating biofilm developed on cover slip with standardized number of lytic phages or gentamicin compared with the control E. coli (untreated cells). Of 30 UPEC strains isolated from patients, 29 (96.6%) of them displayed biofilm forming phenotype. The strains with strongly biofilm positive were 76.6%. Generally, antibiotic resistance for biofilm producing E. coli was found to be high. Virulent phage (FJS4) was isolated which was effective against a strong biofilm former UPEC strain. Application of FJS4 phage or gentamicin to established biofilms have caused significant reduction of the cells within 3 hours of application and almost complete eradication of the cells within 36 hrs of incubation at 37°C. These results uphold the efficacy of phage against biofilm of UPEC and suggest that FJS4 phage may be a potential therapeutic alternative to antimicrobials on inanimate and animate surfaces

Phosphate Solubilization Potential of Rhizosphere Fungi Isolated from Plants in Jimma Zone, Southwest Ethiopia

Phosphorus (P) is one of the major bioelements limiting agricultural production. Phosphate solubilizing fungi play a noteworthy role in increasing the bioavailability of soil phosphates for plants. The present study was aimed at isolating and characterizing phosphate solubilizing fungi from different rhizospheres using both solid and liquid Pikovskaya (PVK) medium. A total of 359 fungal isolates were obtained from 150 rhizosphere soil samples of haricot bean, faba bean, cabbage, tomato, and sugarcane. Among the isolates, 167 (46.52%) solubilized inorganic phosphate. The isolated phosphate solubilizing fungi belonged to genera of Aspergillus (55.69%), Penicillium spp. (23.35%), and Fusarium (9.58%). Solubilization index (SI) ranged from 1.10 to 3.05. Isolates designated as JUHbF95 (Aspergillus sp.) and JUFbF59 (Penicillium sp.) solubilized maximum amount of P 728.77 μg·mL−1 and 514.44 μg mL−1, respectively, from TCP (tricalcium phosphate) after 15 days of incubation. The highest (363 μg mL−1) soluble-P was released from RP with the inoculation of JUHbF95 in the PVK broth after 10 days of incubation. The present study indicated the presence of diverse plant associated P-solubilizing fungi that may serve as potential biofertilizers

Species composition, infection rate and detection of resistant alleles in Anopheles funestus (Diptera: Culicidae) from Lare, a malaria hotspot district of Ethiopia

Abstract Background Anopheles funestus, which is considered as secondary vector of malaria in Ethiopia, is known to have several morphologically indistinguishable (sibling) species. Accurate identification of sibling species is crucial to understand their biology, behaviour and vector competence. In this study, molecular identification was conducted on the Ethiopian An. funestus populations. Moreover, insecticide resistance mechanism markers were detected, including ace N485I, kdr L1014F, L1014S, and CYP6P9a TaqMan qPCR was used to detect the infective stage of the parasite from field collected adult female An. funestus populations. Methods Adult female mosquito collection was conducted from Lare, Gambella Regional State of Ethiopia between June 2018 to July 2020 using CDC light traps and HLC. Sub-samples of the morphologically identified An. funestus mosquitoes were molecularly identified using species-specific PCR, and the possible presence of insecticide resistance alleles was investigated using TaqMan qPCR (N485I-Ace-1), PCR-Sanger sequencing (L1014F-kdr), and PCR–RFLP (CYP6P9a resistance allele). Following head/thorax dissection, the TaqMan qPCR assay was used to investigate the presence of the infective stage Plasmodium parasite species. Results A total of 1086 adult female An. funestus mosquitoes were collected during the study period. All sub-samples (N = 20) that were morphologically identified as An. funestus sensu lato (s.l.) were identified as An. funestus sensu stricto (s.s.) using species- specific PCR assay. The PCR–RFLP assay that detects the CYP6P9a resistance allele that confers pyrethroid resistance in An. funestus was applied in N = 30 randomly selected An. funestus s.l. specimens. None of the specimens showed a digestion pattern consistent with the presence of the CYP6P9a resistance allele in contrast to what was observed in the positive control. Consequently, all samples were characterized as wild type. The qPCR TaqMan assay that detects the N485I acetylcholinesterase-1 mutation conferring resistance to organophosphates/carbamates in An. funestus was used in (N = 144) samples. All samples were characterized as wild type. The kdr L1014F and L1014S mutations in the VGSC gene that confer resistance to pyrethroids and DDT were analysed with direct Sanger sequencing after PCR and clean-up of the PCR products were also characterized as wild type. None of the samples (N = 169) were found positive for Plasmodium (P. falciparum/ovale/malariae/vivax) detection. Conclusion All An. funestus s.l. samples from Lare were molecularly identified as An. funestus s.s. No CYP6P9, N485I acetylcholinesterase 1, kdr L1014F or L1014S mutations were detected in the An. funestus samples. None of the An. funestus samples were positive for Plasmodium. Although the current study did not detect any insecticide resistant mechanism, it provides a reference for future vector monitoring programmes. Regular monitoring of resistance mechanisms covering wider geographical areas of Ethiopia where this vector is distributed is important for improving the efficacy of vector control programs