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Chlorpyrifos poses a danger to the environment as a result of its toxicity and endurance in soil and water. Bioremediation of pesticide-polluted soils is one of the most promising approaches for removing contaminants from the environment. This study aimed to isolate and identify chlorpyrifos-degrading bacterial strains and test their biodegradation capabilities and their roles in plant growth. The 16S rDNA gene sequencing identified the two efficient chlorpyrifos-degrading bacterial strains as Stenotrophomonas maltophilia (RS1) and Acinetobacter calcoaceticus (RS3), which significantly (p < 0.01) degraded 71.3% and 73.5% of chlorpyrifos in the liquid medium, respectively, compared to 80% degradation (p < 0.01) when cultured as a consortium within 48 h. The bioremediation of artificially chlorpyrifos-contaminated soils varied between 84.4% and 90.11% (p < 0.01), depending on the used bacterium and soil sterilization status. Furthermore, the enzymes embroiled in the degradation mechanism were sprinkled all over the cells but with different portions. Experiments on plant growth revealed that chlorpyrifos hurt lettuce growth. The presence of RS1 and RS3, on the other hand, demonstrated considerable lettuce growth-enhancing traits in terms of germination percentages, shoot and root lengths and weights. Our isolates could be promising candidates in the bioremediation of chlorpyrifos-contaminated sites in conjunction with their contribution as biofertilizers.

The extensive use of methomyl as a pesticide contributed to its pervasive existence as a pollutant of soil and water resources. In this study, bacteria were isolated from polluted agricultural soils and identified as Bacillus paramycoides and Bacillus proteolyticus. Their methomyl biodegradation efficiencies were evaluated under various experimental conditions in vitro. Bacterial growth was optimized in terms of methomyl concentrations, resulting in maximum growth at 100 mg/L. A considerable degradation was achieved with methomyl being the sole carbon source. Under these conditions, Bacillus spp. degraded 60.6%–62.9% of methomyl in liquid medium when cultured separately, compared to 74.3% degradation when cultured as a consortium within 48 h. Moreover, methomyl bioremediation of artificially contaminated soil varied between 88.3% and 93.2% depending on the used bacterium and soil sterilization status. Furthermore, cell-free extracts of both isolates were tested to inspect their methomyl-degradation activities. The enzymes implicated in such action were mainly located extracellularly, with a lower quota of enzymes available in the intracellular and periplasmic extract. The tested Bacillus spp. also demonstrated considerable corn growth enhancing traits in terms of germination percentages, shoot and root lengths and weights, which were adversely affected by methomyl application. These results illustrate the beneficial use of Bacillus spp. as promising candidates in the bioremediation of methomyl-contaminated sites in conjunction with their contribution as biofertilizers.

Late in 2020, two genetically-distinct clusters of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with mutations of biological concern were reported, one in the United Kingdom and one in South Africa. Using a combination of data from routine surveillance, genomic sequencing and international travel we track the international dispersal of lineages B.1.1.7 and B.1.351 (variant 501Y-V2). We account for potential biases in genomic surveillance efforts by including passenger volumes from location of where the lineage was first reported, London and South Africa respectively. Using the software tool grinch (global report investigating novel coronavirus haplotypes), we track the international spread of lineages of concern with automated daily reports, Further, we have built a custom tracking website (cov-lineages.org/global_report.html) which hosts this daily report and will continue to include novel SARS-CoV-2 lineages of concern as they are detected.

Late in 2020, two genetically-distinct clusters of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with mutations of biological concern were reported, one in the United Kingdom and one in South Africa. Using a combination of data from routine surveillance, genomic sequencing and international travel we track the international dispersal of lineages B.1.1.7 and B.1.351 (variant 501Y-V2). We account for potential biases in genomic surveillance efforts by including passenger volumes from location of where the lineage was first reported, London and South Africa respectively. Using the software tool grinch (global report investigating novel coronavirus haplotypes), we track the international spread of lineages of concern with automated daily reports, Further, we have built a custom tracking website (cov-lineages.org/global_report.html) which hosts this daily report and will continue to include novel SARS-CoV-2 lineages of concern as they are detected.

Brucella melitensis is the main causative agent of the zoonotic disease brucellosis. This study aimed at typing and characterizing genetic variation in 33 Brucella isolates recovered from patients in Lebanon. Bruce-ladder multiplex PCR and PCR-RFLP of omp31, omp2a and omp2b were performed. Sixteen representative isolates were chosen for draft-genome sequencing and analyzed to determine variations in virulence, resistance, genomic islands, prophages and insertion sequences. Comparative whole-genome single nucleotide polymorphism analysis was also performed. The isolates were confirmed to be B. melitensis. Genome analysis revealed multiple virulence determinants and efflux pumps. Genome comparisons and single nucleotide polymorphisms divided the isolates based on geographical distribution but revealed high levels of similarity between the strains. Sequence divergence in B. melitensis was mainly due to lateral gene transfer of mobile elements. This is the first report of an in-depth genomic characterization of B. melitensis in Lebanon.

Leishmania is a parasitic protozoan with more than two-dozen species causing the disease leishmaniasis. It is transmitted to humans through the bite of an infected female phlebotomine sand-fly vector. In the past two years the incidence of leishmaniasis has been drastically increasing in Lebanon. This was in parallel with the deterioration of the security in Syria forcing thousands to flee and seek shelter in poorly maintained refugee camps and collective shelters. Cutaneous leishmaniasis (CL) is now considered a public health problem, but its epidemiology has not been fully elucidated. To our knowledge, this is the first study comparing two different molecular methods for the detection and identification of Leishmania tropica in Lebanon. Two molecular typing methods of 39 FFPE Leishmania isolates were used: the ITS1-PCR RFLP and the nested ITS1-5.8S rDNA gene amplification followed by sequencing and phylogenetic analysis. The efficiency of these two techniques in Leishmania identification was compared and the phylogenetic relationships among these isolates were illustrated based on the neighbor-joining (NJ) method. The results were statistically correlated with the parasitic index (PI). The DNA storage in formalin-fixed paraffin embedded (FFPE) tissues was assessed as well. The parasites identified were all L. tropica as determined by both techniques. ITS1-5.8S rDNA gene based typing proved to be more sensitive in the detection of parasites (positive in 69.2% of the isolates) as opposed to the ITS1-PCR RFLP method that was successful in identifying L. tropica in only 43.6% of the isolates. Sequencing and phylogenetic analysis revealed high levels of heterogeneity. A statistically significant correlation was observed between PI and the results of the nested ITS1-5.8S rDNA gene PCR. Genotyping at the species level is essential for monitoring the relative frequency of CL in the Mediterranean area that is correlated to three different Leishmania species (Leishmania inf

Sphingomonads comprise a physiologically versatile group many of which appear to be adapted to oligotrophic environments, but several also had features in their genomes indicative of host associations. In this study, the extent variability of the 16S–23S rDNA intergenic spacer (ITS) sequences of 14 ATCC reference sphingomonad strains and 23 isolates recovered from drinking water was investigated through PCR amplification and sequencing. Sequencing analysis of the 16S–23S rRNA gene ITS region revealed that the ITS sizes for all studied isolates varied between 415 and 849 bp, while their G+C content was 42.2–57.9 mol%. Five distinct ITS types were identified: ITSnone (without tRNA genes), ITSAla(TGC), ITSAla(TGC)+Ile(GAT), ITSIle(GAT)+Ala(TGC), and ITS Ile(GAT)+Pseudo. All of the identified tRNAAla(TGC) molecules consisted of 73 bases, and all of the tRNAIle(GAT) molecules consisted of 74 bases. We also detected striking variability in the size of the ITS region among the various examined isolates. Highest variability was detected within the ITS-2. The importance of this study is that this is the first comparison of the 16S–23S rDNA ITS sequence similarities and tRNA genes from sphingomonads. Collectively the data obtained in this study revealed the heterogeneity and extent of variability within the ITS region compared to the 16S rRNA gene within closely related isolates. Sequence and length polymorphisms within the ITS region along with the ITS types (tRNA-containing or lacking and the type of tRNA) and ITS-2 size and sequence similarities allowed us to overcome the limitation we previously encountered in resolving closely related isolates based on the 16S rRNA gene sequence.

Purpose: Streptococcus pneumoniae is an important human pathogen causing invasive pneumococcal diseases (IPD). The re-emergence of eradicated S. pneumoniae-associated meningoencephalitis in Lebanon is a major point of concern. Methods: We aimed at conducting a comparative genome analysis of a multi-drug resistant S. pneumoniae, LAU-23F, linked to meningoencephalitis and fatality in a 10-months Syrian refugee infant in Lebanon, and 24 related publically available genome sequences. Serotype, capsular genes, MLST, SNPs, phylogenetic relatedness and repertoire of resistance genes were investigated. Genes encoding penicillin binding proteins (PBPs) were examined for mosaicity. Virulence factors were screened for SNPs as compared to reference strains. Results: The isolate belonged to ST-277 and was of serotype 23F. It showed an intermediate resistance to ciprofloxacin, cefuroxime and penicillin and carried multiple components of different efflux pumps. Gene mosaicity was observed in pbp2x, it was also distinct from other penicillin-resistant strains; pbp1a and pbp2b appeared to be conserved between LAU-23F and the reference strain SP49. The arrangement of capsular gene loci was similar to ATCC 700669 though polymorphism was detected in the cpsABCD region, believed to be conserved among different Streptococcus species. Amplitude of virulence factors was detected showing varying degrees of conservation compared to reference strains. Observed zones of high heterogeneity were associated with phage encoded regions. Conclusions: The fine levels of diversity throughout the genome could account for the pronounced invasiveness of this isolate. The genomicsbased methods used support the importance of implementing WGS in routine clinical diagnostics and surveillance of streptococcal diseases.

The class D carbapenemase OXA-48 was first detected in 2001 from a carbapenem-resistant Klebsiella pneumoniae isolate in Istanbul, Turkey [1]. The variant OXA-181, which differs from OXA-48 by four amino acids, was isolated later in India in 2007 from Enterobacter cloacae and K. pneumoniae. Since then, OXA-181 has been reported in Bangladesh, India, South Africa, Canada, France and New Zealand [2,3]. Here we report the first case of OXA-181-producing Escherichia coli identified in Lebanon.

We present here the draft genome sequences of multidrug-resistant blaNDM-1-positive Acinetobacter baumannii strains ACMH-6200 and ACMH-6201, isolated in north Lebanon from civilians wounded during the Syrian civil war. The draft genomes were contained in 217 contigs for ACMH-6200 and 83 contigs for ACMH-6201, including a combined 3,997,237 bases for ACMH-6200 and 3,983,110 bases for ACMH-6201, with 39% and 38.9% G+C content, respectively.