Chromosomal and plasmid-encoded virulence and multidrug resistance of Escherichia coli ST58/24 infecting a 2-year-old sickle cell patient with sepsis in Kampala Uganda, East Africa.

Sepsis and drug resistance represent a complex of the most common global causes of mortality in intensive care units (ICUs) especially among patients with comorbidities. Extraintestinal pathogenic Escherichia coli (ExPEC) strains are highly implicated in systemic infections, with multidrug resistance exacerbating the risk of chronic conditions and patient mortality. The diversity of virulence and evolution of multidrug resistance are yet to be fully deciphered. In this work, we aimed at unveiling the pathogens and their genomic determinants of virulence and drug resistance relevant to increased sepsis in a sickle cell child admitted to ICU. From a rectal swab, we isolated a strain of E. coli from the patient and phenotypically tested it against a panel of selected beta lactams, fluoroquinolones, macrolides, aminoglycosides and colistin. We then sequenced the entire genome and integrated multiple bioinformatic pipelines to divulge the virulence and multidrug resistance profiles of the isolate. Our results revealed that the isolate belongs to the sequence type (ST) 58/24, which (ST58), is a known ExPEC. With the use of PathogenFinder, we were able to confirm that this isolate is a human pathogen (p = 0.936). The assembled chromosome and two plasmids encode virulence factors related to capsule (antiphagocytosis), serum survival and resistance, type 6 secretion system (T6SS), multiple siderophores (iron acquisition), and biosynthetic gene clusters for polyketides and nonribosomal peptides exhibiting host cell damaging activity in silico. The genome also harbors multidrug resistance genotypes including extended spectrum beta lactamase (ESBL) genes such as blaTEM-1A/B, sulfonamide resistance genes sul1/2, fluoroquinolone resistance genes dfrA5 and nonsynonymous mutations of the gene pmrB, conferring intrinsic colistin resistance. Conclusively, this pathogen holds the potential to cause systemic infection and might exacerbate sickle cell anemia in the patient. The virulence and multidrug resistance profiles are encoded by both the chromosome and plasmids. Genomic surveillance of pathogens with multidrug resistance among patients with commodities is crucial for effective disease management.

A sophisticated virulence repertoire and colistin resistance of Citrobacter freundii ST150 from a patient with sepsis admitted to ICU in a tertiary care hospital in Uganda, East Africa: Insight from genomic and molecular docking analyses.

Sepsis and multidrug resistance comprise a complex of factors attributable to mortality among intensive care unit (ICU) patients globally. Pathogens implicated in sepsis are diverse, and their virulence and drug resistance remain elusive. From a tertiary care hospital ICU in Uganda, we isolated a Citrobacter freundii strain RSM030 from a patient with sepsis and phenotypically tested it against a panel of 16 antibiotics including imipenem levofloxacin, cotrimoxazole and colistin, among others. We sequenced the organism's genome and integrated multilocus sequencing (MLST), PathogenFinder with Virulence Factor analyzer (VFanalyzer) to establish its pathogenic relevance. Thereafter, we combined antiSMASH and PRISM genome mining with molecular docking to predict biosynthetic gene clusters (BGCs), pathways, toxin structures and their potential targets in-silico. Finally, we coupled ResFinder with comprehensive antibiotic resistance database (CARD) to scrutinize the genomic antimicrobial resistance profile of the isolate. From PathogenFinder and MLST, this organism was confirmed to be a human pathogen (p = 0.843), sequence type (ST)150, whose virulence is determined by chromosomal type III secretion system (T3SS) (the injectosome) and plasmid-encoded type IV secretion system (T4SS), the enterobactin biosynthetic gene cluster and biofilm formation through the pgaABCD operon. Pathway and molecular docking analyses revealed that the shikimate pathway can generate a toxin targeting multiple host proteins including spectrin, detector of cytokinesis protein 2 (Dock2) and plasmalemma vesicle-associated protein (PLVAP), potentially distorting the host cell integrity. From phenotypic antibiotic testing, we found indeterminate results for amoxicillin/clavulanate and levofloxacin, with resistance to cotrimoxazole and colistin. Detailed genome analysis revealed chromosomal beta lactam resistance genes, i.e. blaCMY-79, blaCMY-116 and blaTEM-1B, along with multiple mutations of the lipopolysaccharide modifying operon genes PmrA/PmrB, pmrD, mgrA/mgrB and PhoP/PhoQ, conferring colistin resistance. From these findings, we infer that Citrobacter freundii strain RSM030 is implicated in sepsis and resistance to standard antibiotics, including colistin, the last resort.

Assessing the effect of sample storage time on viral detection using a rapid and cost-effective CTAB-based extraction method.

BACKGROUND: Cassava leaf samples degrade quickly during storage and transportation from distant areas. Proper sampling and efficient, low-cost storage methods are critical for obtaining sufficient quality DNA and RNA for plant virus epidemiology and improving disease control understanding. This is useful when samples are collected from remote areas far from a laboratory or in developing countries where money and materials for virus diagnostics are scarce. RESULTS: The effect of sample storage duration on nucleic acid (N.A.) quality on virus detection was investigated in this study. A simple, rapid, and cost-effective CTAB-based approach (M3) for single N.A. extraction was optimized and tested alongside two existing CTAB-based methods (M1 and M2) for N.A. extraction from fresh and herbarium cassava leaves stored for; 1, 8, 26, and 56 months. The amount and quality of DNA and RNA were determined using Nanodrop 2000 c U.V.-vis Spectrophotometer and agarose gel electrophoreses. The sample degradation rate was estimated using a simple mathematical model in Matlab computational software. The results show no significant difference in mean DNA concentration between M1 and M2 but a significant difference between M3 and the other two methods at p < 0.005. The mean DNA concentration extracted using M3 was higher for 1 and 8 months of leave storage. M3 and M2 produced high concentrations at 26 and 56 months of leave storage. Using a developed scale for quality score, M3 and M2 produced high-quality DNA from fresh samples. All methods produced poor-quality DNA and RNA at 8 and 26 months of leave storage and no visual bands at the age of 56 months. Statistically, there was a significant difference in the mean DNA quality between M1 and M2, but there was no significant difference between M3 and the other two methods at p < 0.005. However, Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV) were readily detected by RT-PCR from RNA isolated using M3. The quality of DNA declined per storage time at 0.0493 and 0.0521/month, while RNA was 0.0678 and 0.0744/month. Compared to the existing two methods, modified CTAB extracted enough high-quality N.A. in one-third the time of the existing two methods. CONCLUSION: Our method provides cost-effective, quick, and simple processing of fresh and dry samples, which will quicken and guide the decision on when and what type of sample to process for plant disease management and surveillance actions.

Complete genome sequence data of Priestia megaterium strain MARUCO02 isolated from marine mangrove-inhabited sediments of the Indian Ocean in the Bagamoyo Coast.

Priestia is a genus of biotechnologically important bacteria adapted to thrive in a wide range of environmental conditions including the marine sediments. Here, we screened and isolated a strain from the Bagamoyo marine mangrove-inhabited sediments and then employed whole genome sequencing to recover and define its full genome. De novo-assembly with Unicycler (v. 0.4.8) and annotation with Prokaryotic Genome Annotation Pipeline (PGAP) revealed that that its genome contains one chromosome (5,549,131 bp), with a GC content of 37.62%. Further analysis showed that the genome contains 5,687 coding sequences (CDS), 4 rRNAs, 84 tRNAs, 12 ncRNAs, and at least 2 plasmids (1,142 bp and 6,490 bp). On the other hand, antiSMASH-based secondary metabolite analysis revealed that the novel strain (MARUCO02) contains gene clusters for biosynthesis of MEP-DOXP-dependent versatile isoprenoids (eg. carotenoids), siderophores (synechobactin and schizokinen) and polyhydroxyalkanoates (PHA). The genome dataset also informs about the presence genes encoding enzymes required for generation of hopanoids, compounds that confer adaption to harsh environmental conditions including industrial cultivation recipes. Our data from this novel Priestia megaterium strain MARUCO02 can be used for reference and in genome-guided selection of strains for production of isoprenoids as well as industrially useful siderophores and polymers, amenable for biosynthetic manipulations in a biotechnological process.

Complete genome sequence of Bacillus subtilis strain MARUCo01 isolated from marine sediments of the Indian Ocean in Bagamoyo, Tanzania.

Bacillus subtilis has emerged as a species with potential for versatile nonribosomal peptides and polyketides of therapeutic importance, including antibiotics. From our molecular bioprospecting project, we report a full genome of Bacillus subtilis strain MARUCo01 locally isolated from sediments of the Indian Ocean along the coast of Bagamoyo in Tanzania.

Draft Genome Sequence of Limnospira sp. Strain BM01, Isolated from a Hypersaline Lake of the Momela Ecosystem in Tanzania.

The genus Limnospira includes cyanobacterial species used for industrial production of dietary supplements and nutraceutical agents. The metagenome-assembled genome of Limnospira sp. strain BM01 from Big Momela Lake, Tanzania, was 6,228,312 bp long with a GC content of 44.8% and carried 4,921 proteins and 52 RNA genes, including 6 rRNA genes.

Metabolic potential of the moderate halophile Yangia sp. ND199 for co-production of polyhydroxyalkanoates and exopolysaccharides.

Yangia sp. ND199 is a moderately halophilic bacterium isolated from mangrove samples in Northern Vietnam, which was earlier reported to grow on several sugars and glycerol to accumulate poly(hydroxyalkanoates) (PHA). In this study, the potential of the bacterium for co-production of exopolysaccharides (EPS) and PHA was investigated. Genome sequence analysis of the closely related Yangia sp. CCB-M3 isolated from mangroves in Malaysia revealed genes encoding enzymes participating in different EPS biosynthetic pathways. The effects of various cultivation parameters on the production of EPS and PHA were studied. The highest level of EPS (288 mg/L) was achieved using sucrose and yeast extract with 5% NaCl and 120 mM phosphate salts but with modest PHA accumulation (32% of cell dry weight, 1.3 g/L). Growth on fructose yielded the highest PHA concentration (85% of CDW, 3.3 g/L) at 90 mM phosphate and higher molecular weight EPS at 251 mg/L yield at 120 mM phosphate concentration. Analysis of EPS showed a predominance of glucose, followed by fructose and galactose, and minor amounts of acidic sugars.

Ligand-protein interactions of plant-isolated (9z,12z)-octadeca-9,12-dienoic acid with Β-ketoacyl-Acp synthase (KasA) in potential anti-tubercular drug designing.

Mycobacterium tuberculosis remains one of the world's contributors to mortality. With the emergence of SARS-CoV-2 coinfections, patients with TB are predisposed to being more heavily weighed down by COVID-19 disease and its opportunistic coinfections. The severity of the disease coupled with drug resistance on the currently used drugs warrants for the search for alternative remedies from synthetic agents, semisynthetics and natural products that include plants. Africa is rich in plant diversity with a promise as sources of drug agents, one of which is Eichhornia crassipes. This work aimed at isolating a fatty acid and dock it to ß-ketoacyl-ACP synthase for possible anti-TB drug development prospects using computational tools. (9z,12z)-Octadeca-9,12-dienoic acid was isolated from Eichhornia crassipes for the first time using chromatographic techniques and identified using 1D and 2D NMR spectroscopic methods (1H NMR, COSY, HSQC, HMBC and 13C NMR). The compound was then docked to ß-ketoacyl-ACP synthase (KasA), an essential member of the b-ketoacyl synthases encoded in the M. tuberculosis genome in comparison with its co-crystallized ligand JSF-3285, also for the first time. (9z,12z)-Octadeca-9,12-dienoic acid interacted with only phenylalanine239 and proline201 while JSF-3285 interacted with proline201, glutamine120, alanine119, leucine116, glutamine199, histadine345, phenylalanine239, glycine240 and glycine200. (9z,12z)-Octadeca-9,12-dienoic acid had a ligand efficiency of 0.24, compared to the co-crystallized ligand's 0.36. The compound was too flexible and elongated with -4.72 KCalmol-1 binding energy. Despite some unfavourable physico-chemical properties, the compound still provides reliable interactions that only require logical structural modifications by the addition of polar regions amongst others to increase interactions and ligand efficiency, which can consequently stand to be a better potential drug lead. For the first time, plant-based (9z,12z)-Octadeca-9,12-dienoic acid isolated from Eichhornia crassipes was shown to interact fairly well with ß-ketoacyl-ACP synthase and proved to be a potential starting material from which anti-tubercular drugs can be designed.

Application of Viral Metagenomics for Study of Emerging and Reemerging Tick-Borne Viruses.

Ticks are important vectors for different tick-borne viruses, some of which cause diseases and death in humans, livestock, and wild animals. Tick-borne encephalitis virus, Crimean-Congo hemorrhagic fever virus, Kyasanur forest disease virus, severe fever with thrombocytopenia syndrome virus, Heartland virus, African swine fever virus, Nairobi sheep disease virus, and Louping ill virus are just a few examples of important tick-borne viruses. The majority of tick-borne viruses have RNA genomes that routinely undergo rapid genetic modifications such as point mutations during their replication. These genomic changes can influence the spread of viruses to new habitats and hosts and lead to the emergence of novel viruses that can pose a threat to public health. Therefore, investigation of the viruses circulating in ticks is important to understand their diversity, host and vector range, and evolutionary history, as well as to predict new emerging pathogens. The choice of detection method is important, as most methods detect only those viruses that have been previously well described. On the other hand, viral metagenomics is a useful tool to simultaneously identify all the viruses present in a sample, including novel variants of already known viruses or completely new viruses. This review describes tick-borne viruses, their historical background of emergence, and their reemergence in nature, and the use of viral metagenomics for viral discovery and studies of viral evolution.

Omics for Bioprospecting and Drug Discovery from Bacteria and Microalgae.

"Omics" represent a combinatorial approach to high-throughput analysis of biological entities for various purposes. It broadly encompasses genomics, transcriptomics, proteomics, lipidomics, and metabolomics. Bacteria and microalgae exhibit a wide range of genetic, biochemical and concomitantly, physiological variations owing to their exposure to biotic and abiotic dynamics in their ecosystem conditions. Consequently, optimal conditions for adequate growth and production of useful bacterial or microalgal metabolites are critically unpredictable. Traditional methods employ microbe isolation and 'blind'-culture optimization with numerous chemical analyses making the bioprospecting process laborious, strenuous, and costly. Advances in the next generation sequencing (NGS) technologies have offered a platform for the pan-genomic analysis of microbes from community and strain downstream to the gene level. Changing conditions in nature or laboratory accompany epigenetic modulation, variation in gene expression, and subsequent biochemical profiles defining an organism's inherent metabolic repertoire. Proteome and metabolome analysis could further our understanding of the molecular and biochemical attributes of the microbes under research. This review provides an overview of recent studies that have employed omics as a robust, broad-spectrum approach for screening bacteria and microalgae to exploit their potential as sources of drug leads by focusing on their genomes, secondary metabolite biosynthetic pathway genes, transcriptomes, and metabolomes. We also highlight how recent studies have combined molecular biology with analytical chemistry methods, which further underscore the need for advances in bioinformatics and chemoinformatics as vital instruments in the discovery of novel bacterial and microalgal strains as well as new drug leads.