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AbstractThirty-four different soil Streptomyces isolates previously recovered from soils of different gas stations that were historically polluted with fuel oil for long time were analyzed for their ability to produce five different hydrolytic enzymes, as well as for their potential to use diesel fuel as a sole carbon source for growth, in addition to the PCR amplification of the alkane hydroxylase gene (alkB). Results showed that 97.68% were producing at least one of the five hydrolytic enzymes, pectinase, carboxymethyl cellulase (CMCase), lipase, chitinase or amylase. Three isolates (1a, 5e, and 12a) were only producing all the tested enzymes and were able to use diesel fuel as a sole carbon source for growth as assessed by biochemical enzymatic assay and dry weight measurements. The capability of these isolates to use diesel as a sole carbon source for growth was obvious by changing the colourcolour of the reaction mixture within 6 hours, and the increase in dry weight after incubation for 28 days. Although the three isolates showed diesel degrading capability, they tested negative for harbouring the alkB gene by the PCR assay. alkB gene might not be the only gene responsible for alkanes degradation, and the isolates that grew on diesel and showed no PCR product might devoid the alkB gene.

Rhizoctonia solani (teleomorph: Thanatephorus cucumeris) is a global soil-borne pathogen that severely harms potato crops, leading to significant product losses. Black scurf and stem canker are two manifestations caused by this pathogen, with variable intensity based on the distinctive anastomosis group endemic to the region. During the growing season of 2017 (March and April), 57 different fungus isolates were collected from potato crops farmed in the Jordan Valley. The identity of all the isolates was confirmed by sequencing the internal transcribed spacer (ITS) of the ribosomal DNA gene, and the hyphal interactions were also performed with R. solani isolates. The sequences were deposited in GenBank, where accession numbers were obtained. 21 of the isolates were AG-3PT R. solani, with 98–99% identity to reference strains. Somatic compatibility was determined by hyphal interactions, which showed pairing compatibility among the isolates. Around 86.7% of the pairings were somatically incompatible, indicating a high level of genetic diversity among the isolates, while only 13.3% of the pairings were somatically compatible. Testing for pathogenicity revealed that AG-3PT affected the stems of solanaceous plants, including potatoes, and the roots of other plant species. Based on the findings of this study, R. solani AG-3PT was the primary pathogen associated with potato stem canker and black scurf diseases in Jordan. To our knowledge, this is the first report on this pathogen's isolation and identification in Jordan.

The objectives of this study were to assess the microbial quality of honey, evaluate the effect of microwaves on microbial survival, and assess the antibacterial activity of honey. Bacteria, yeast and mold were evaluated in samples before and after microwave treatment. Dominant bacterial contaminants were also identified. The antibacterial activity of honey was assessed against nine pathogens using an agar well diffusion assay. The minimum inhibitory concentration was determined for four honey samples that exhibited the highest antibacterial activity. In addition, one sample of Manuka honey was tested to compare its microbial load as well as its antibacterial activity to local honey samples. Sequencing using 16S rRNA gene was used for the identification of dominant bacteria. The average standard plate count, yeasts and molds were 286.5,161.0 and 25.5 CFU/g, respectively. Microwave treatment decreased microbial populations gradually with increasing power levels and exposure times. The present study indicated that raw honey had a significant antibacterial activity which decreased following microwave treatment. The identity of 125 isolates was confirmed with Bacillus being most frequently isolated.

Abstract Acinetobacter baumannii is a Gram-negative bacterium that has gained a stronghold inside healthcare settings. Due to the ability of A. baumannii to acquire antibiotic resistance easily, its presence in food products could pose a major threat to the public health. The aim of this study therefore, was to investigate the prevalence of A. baumannii in fresh produce and study their genetic diversity. A total of 234 samples of vegetables and fruits were collected. A. baumannii isolates were identified using CHROMagar and two different PCR assays. Also, the isolates were tested for their ability to resist antibiotics and form biofilms. The genetic diversity of the isolates was determined using multi-locus sequence typing (MLST). Of the 234 samples collected, 10 (6.5%) and 7 (8.75%) A. baumannii isolates were recovered from vegetables and fruits, respectively. Antibiotic susceptibility testing revealed that 4 of these isolates were extensively drug-resistant (XDR). All isolates were able to form biofilms and MLST analysis revealed 6 novel strains. This study demonstrated that fresh produce constitutes a reservoir for A. baumannii, including strong biofilm formers and XDR strains. This represents a significant concern to public health because vegetables and fruits may serve as a vehicle for the spread of A. baumannii and antibiotic resistance into the community and healthcare settings.

Acinetobacter baumannii is one of the most successful pathogens that can cause difficult-to-treat nosocomial infections. Outbreaks and infections caused by multi-drug resistant A. baumannii are prevalent worldwide, with only a few antibiotics are currently available for treatments. Plasmids represent an ideal vehicle for acquiring and transferring resistance genes in A. baumannii. Five extensively drug-resistant A. baumannii clinical isolates from three major Jordanian hospitals were fully sequenced. Whole-Genome Sequences (WGS) were used to study the antimicrobial resistance and virulence genes, sequence types, and phylogenetic relationship of the isolates. Plasmids were characterized In-silico, followed by conjugation, and plasmid curing experiments. Eight plasmids were recovered; resistance plasmids carrying either aminoglycosides or sulfonamide genes were detected. Chromosomal resistance genes included blaOXA-66, blaOXA-91, and blaOXA-23,and the detected virulence factors were involved in biofilm formation, adhesion, and many other mechanisms. Conjugation and plasmid curing experiments resulted in the transfer or loss of several resistance phenotypes. Plasmid profiling along with phylogenetic analyses revealed high similarities between two A. baumannii isolates recovered from two different intensive care units (ICU). The high similarities between the isolates of the study, especially the two ICU isolates, suggest that there is a common A. baumannii strain prevailing in different ICU wards in Jordanian hospitals. Three resistance genes were plasmid-borne, and the transfer of the resistance phenotype emphasizes the role and importance of conjugative plasmids in spreading resistance among A. baumannii clinical strains.

Al-Zarqa River is the second main tributary to River Jordan after the Yarmouk River. The river flow has been modified by discharge of industrial wastewater and treated domestic water. Concerns about the occurrence of waterborne pathogenic viruses in the surface waters of Al-Zarqa River prompted the analysis of the surface water quality with respect to the presence of enteric viruses. Viruses were concentrated from a total of 33 different water environmental samples including raw sewage, effluent samples and river water collected from and around the river over a period of 11 months. Calculated recovery yields for these concentration methods ranged between 2 and 8%. Polymerase chain reaction (PCR), reverse transcriptase-PCR (RT-PCR), nested RT-PCR and southern blotting hybridization analysis were used for the detection of hepatitis A virus, norovirus, astrovirus and human adenovirus 40/41, with the later one being detected in 21 (64%) of the samples that also showed previous positive presence for enteroviruses. To our knowledge, this is the first molecular biology report in Jordan describing the circulation of adenoviruses, which were detected more frequently than enteroviruses in sewage and water samples, and therefore, they can be used as an index for the presence of human pathogenic viruses in water environment. HIGHLIGHTS Occurrence of waterborne pathogenic viruses in water resources.; Circulation of adenoviruses from and around Al-Zarqa River, Jordan.; Implementation of techniques for concentrating viruses from surface and treated water, and raw sewage.; Genomic content of enteric viruses was detected by molecular techniques.; Adenoviruses can be used as an index for the presence of human pathogenic viruses in water environment.;

Cronobacter sakazakii continues to be isolated from ready-to-eat fresh and frozen produce, flours, dairy powders, cereals, nuts, and spices, in addition to the conventional sources of powdered infant formulae (PIF) and PIF production environments. To understand the sequence diversity, phylogenetic relationship, and virulence of C. sakazakii originating from plant-origin foods, comparative molecular and genomic analyses, and zebrafish infection (ZI) studies were applied to 88 strains. Whole genome sequences of the strains were generated for detailed bioinformatic analysis. PCR analysis showed that all strains possessed a pESA3-like virulence plasmid similar to reference C. sakazakii clinical strain BAA-894. Core genome analysis confirmed a shared genomic backbone with other C. sakazakii strains from food, clinical and environmental strains. Emerging nucleotide diversity in these plant-origin strains was highlighted using single nucleotide polymorphic alleles in 2000 core genes. DNA hybridization analyses using a pan-genomic microarray showed that these strains clustered according to sequence types (STs) identified by multi-locus sequence typing (MLST). PHASTER analysis identified 185 intact prophage gene clusters encompassing 22 different prophages, including three intact Cronobacter prophages: ENT47670, ENT39118, and phiES15. AMRFinderPlus analysis identified the CSA family class C β-lactamase gene in all strains and a plasmid-borne mcr-9.1 gene was identified in three strains. ZI studies showed that some plant-origin C. sakazakii display virulence comparable to clinical strains. Finding virulent plant-origin C. sakazakii possessing significant genomic features of clinically relevant STs suggests that these foods can serve as potential transmission vehicles and supports widening the scope of continued surveillance for this important foodborne pathogen.

Abstract  The investigation aimed to examine the Streptomyces flora of hydrocarbon-contaminated soil and study their capability to grow on diesel fuel as a sole carbon source and their analysis for the presence of the alkane hydroxylase gene (alkB) by PCR. A total of 16 Streptomyces isolates were recovered from hydrocarbon-contaminated soil samples on starch casein nitrate agar medium with the ability of 3 isolates to grow on diesel as evaluated by agar plate diffusion method, enzymatic assay and dry weight measurements. PCR analysis of the isolates for the presence of the alkB gene showed two groups with different band size products; group 1 (G1) (316–334 bp) and group 2 (G2) (460–550 bp). Three isolates (SF.1Ac, SF.2Ba, and SF.3Ad) grew around diesel-containing wells and contained the alkB gene with size band ranged between 320 and 550 bp. However; one isolate (SF.1Aa) did not show any PCR product although it was able to grow on diesel. This implies that the alkB gene is not the only gene that is responsible for the degradation of alkanes. Further, the variation in the G2 fragment size probably indicates different related genes that might be involved in alkane degradation rather than a single gene. [ABSTRACT FROM AUTHOR]

Abstract  A total of 161 different Streptomyces isolates were recovered from 5 soil samples representing the driest habitats of Jordan. These were then characterized and assessed for their antagonistic activity against four clinical multi-drug resistant Pseudomonas aeruginosa test pathogens. Results indicated that only 3 strains out of 139 and 6 out of 22 isolated at 27°C and 45°C, respectively, were active against at least three strains of pathogenic Pseudomonas. However, three Streptomyces strains (J2b, J4, and J12) that were isolated at 45°C inhibited all of the tested pathogens with an inhibition zone ranging between 5 and 16 mm in diameter. Data obtained from comparing the inhibition activity of these unique Streptomyces strains toward multi-resistant Pseudomonas pathogens with standard used antibiotics revealed that these isolates produce possible different inhibitory bioactive compounds other than the standard antibiotics. [ABSTRACT FROM AUTHOR]