Fecal Carriage of Colibactin-Encoding Escherichia coli Associated With Colorectal Cancer Among a Student Populace.

Fecal carriage of the colibactin (clb) gene in Escherichia coli is described as a source that could promote carcinogenesis, progressing to colorectal cancer. The present study investigated the demographic, dietary, and antibiotic consumption variables as correlates for fecal carriage of clb+/E coli among the student populace. In a randomized cross-sectional survey, E coli (N = 136) from the fecal samples of eligible students were characterized and evaluated for antibiotic resistance, ß-lactamase (blm), biofilm, virulence factor production, and strain tryptophan reverse mutagenic activity. The encoded clb+/E coli were analyzed for correlates with principal component analysis. Of all the E coli strains, a low rate of 2 clb+/E coli (1.5%) and higher rates of biofilm (13.2%) and blm producers (11.8%) were recorded among the mutant strains as compared with the nonmutant types. All the clb+/E coli showed complete resistance to amoxicillin, Augmentin (amoxicillin and clavulanate), gentamicin, and trimethoprim/sulfamethoxazole. The fecal clb-encoded E coli (1.5%) were not associated with demographic status, fiber-based food (odds ratio [OR], 1.03; 95% CI, 56.74-138.7; P = .213), alcohol (OR, 1.27; 95% CI, 61.74-147.1; P = .221), antibiotic consumptions (OR, 1.11; 95% CI, 61.29-145.3; P = .222), and handwashing (OR, 1.17; 95% CI, 60.19-145.5; P = .216). The hierarchical cluster of blm+/E coli revealed high-level resistance with a multiantibiotic resistance index ≥0.2 (P < .05). Only 12% of all strains were tryptophan mutant/blm+, and 1.5% of clb+/ECblm+ were observed in fecal samples with a 452-base pair size. Trimethoprim/sulfamethoxazole and biofilm production positively regressed with clb expression (P > .05). Principal component analysis score plot indicated an association of clb+/ECblm+ with dietary pattern, alcohol, blm, and hemolysin production. The combined activity of blm and biofilm production in the gut microbiota could promote clb+/E coli colonization, facilitating genotoxin production and possible colorectal cancer induction.

Nutritional, functional, and bioactive properties of african underutilized legumes.

Globally, legumes are vital constituents of diet and perform critical roles in maintaining well-being owing to the dense nutritional contents and functional properties of their seeds. While much emphasis has been placed on the major grain legumes over the years, the neglected and underutilized legumes (NULs) are gaining significant recognition as probable crops to alleviate malnutrition and give a boost to food security in Africa. Consumption of these underutilized legumes has been associated with several health-promoting benefits and can be utilized as functional foods due to their rich dietary fibers, vitamins, polyunsaturated fatty acids (PUFAs), proteins/essential amino acids, micro-nutrients, and bioactive compounds. Despite the plethora of nutritional benefits, the underutilized legumes have not received much research attention compared to common mainstream grain legumes, thus hindering their adoption and utilization. Consequently, research efforts geared toward improvement, utilization, and incorporation into mainstream agriculture in Africa are more convincing than ever. This work reviews some selected NULs of Africa (Adzuki beans (Vigna angularis), African yam bean (Sphenostylis stenocarpa), Bambara groundnut (Vigna subterranea), Jack bean (Canavalia ensiformis), Kidney bean (Phaseolus vulgaris), Lima bean (Phaseolus lunatus), Marama bean (Tylosema esculentum), Mung bean, (Vigna radiata), Rice bean (Vigna Umbellata), and Winged bean (Psophocarpus tetragonolobus)), and their nutritional, and functional properties. Furthermore, we highlight the prospects and current challenges associated with the utilization of the NULs and discusses the strategies to facilitate their exploitation as not only sources of vital nutrients, but also their integration for the development of cheap and accessible functional foods.

Evaluation of Efflux-Mediated Resistance and Biofilm formation in Virulent Pseudomonas aeruginosa Associated with Healthcare Infections.

Pseudomonas aeruginosa is a significant pathogen identified with healthcare-associated infections. The present study evaluates the role of biofilm and efflux pump activities in influencing high-level resistance in virulent P. aeruginosa strains in clinical infection. Phenotypic resistance in biotyped Pseudomonas aeruginosa (n = 147) from diagnosed disease conditions was classified based on multiple antibiotic resistance (MAR) indices and analysed with logistic regression for risk factors. Efflux pump activity, biofilm formation, and virulence factors were analysed for optimal association in Pseudomonas infection using receiver operation characteristics (ROC). Age-specificity (OR [CI] = 0.986 [0.946-1.027]), gender (OR [CI] = 1.44 [0.211-9.827]) and infection sources (OR [CI] = 0.860 [0.438-1.688]) were risk variables for multidrug resistance (MDR)-P. aeruginosa infection (p < 0.05). Biofilm formers caused 48.2% and 18.5% otorrhea and wound infections (95% CI = 0.820-1.032; p = 0.001) respectively and more than 30% multidrug resistance (MDR) strains demonstrated high-level efflux pump activity (95% CI = 0.762-1.016; p = 0.001), protease (95% CI = 0.112-0.480; p = 0.003), lipase (95% CI = 0.143-0.523; p = 0.001), and hemolysin (95% CI = 1.109-1.780; p = 0.001). Resistance relatedness of more than 80% and 60% to cell wall biosynthesis inhibitors (ceftazidime, ceffproxil, augumentin, ampicillin) and, DNA translational and transcriptional inhibitors (gentamicin, ciprofloxacin, ofloxacin, nitrofurantoin) were observed (p < 0.05). Strong efflux correlation (r = 0.85, p = 0.034) with MDR strains, with high predictive performances in efflux pump activity (ROC-AUC 0.78), biofilm formation (ROC-AUC 0.520), and virulence hierarchical-clustering. Combine activities of the expressed efflux pump and biofilm formation in MDR-P. aeruginosa pose risk to clinical management and infection control.

Emerging vancomycin-non susceptible coagulase negative Staphylococci associated with skin and soft tissue infections.

BACKGROUNDS: Observable emergence of Vancomycin-Non susceptible Coagulase-negative Staphylococci (VNS-CoNS) associated with skin and soft tissue infections spreading among the urban and rural populace is gradually intensifying severe complications. The isolated VNS-CoNS were evaluated with Matrix-assisted Laser Desorption/ionization Time of Flight Mass Spectrometry (MALDI ToF MS) for species characterization and pan-antimicrobial resistance pattern. METHODS: Out of 256 clinical samples collected including pus, abscess, ear swabs, eye swabs, and aspirates, 91 CoNS isolates were biotyped and further characterized with MALDI-TOF MS. Staphylococci marker genes, Vancomycin susceptibility, and biofilm assays were performed. RESULTS: Of 91 CoNS isolates, S.cohnii (2.3%), S.condimentii (3.4%), S. saprophyticus (6.7%), and S.scuri (21.1%) were characterized with MALDI-TOF with significant detection rate (99.4%; CI 95, 0.775-0.997, positive predictive values, 90.2%) compared to lower biotyping detection rate (p = 0.001). Hemolytic VNS-CoNS lacked nuc, pvl and spa genes from wound, ear, and aspirates of more 0.83 MARI clustered into a separate phylo-diverse group and were widely distributed in urban and peri-urban locations. MALDI TOF-MS yielded a high discriminatory potential of AUC-ROC score of 0.963 with true-positivity prediction. VNS-CoNS of MIC ≥ 16 µg/mL were observed among all the ages with significant resistance at 25th and 75th quartiles. More than 10.5% of CoNS expressed multi-antibiotic resistance with more than 8 µg/mL vancomycin cut-off values (p < 0.05). CONCLUSION: Antibiotic resistant CoNS should be considered significant pathogens rather than contaminant. Biofilm producing VNS-S. sciuri and S. condimentii are potential strains with high pathological tropism for skin, soft tissues and wound infections, and these strains require urgent surveillance in peri-urban and rural communities.

African fermented foods: overview, emerging benefits, and novel approaches to microbiome profiling.

Traditional fermented foods are of major importance with respect to the socio-economic growth, food security, nutrition, and health of African consumers. In several African countries, traditional fermentation processes provide a means of food preservation, improving the shelf life and adding to the nutrients in the food products. As with any fermented foods, the associated food microbiota is of great importance and interest. Recent studies on the microbiome of African fermented foods using high-throughput DNA sequencing techniques have revealed the presence of diverse microbial populations of fundamental, technological, and commercial interest that could be harnessed to further improve health, food safety, and quality. This review provides an overview of African fermented foods, their microbiota, and the health-promoting potential of these foods and microbes.

Evolutionary dynamics and geographic dispersal of beta coronaviruses in African bats.

Bats have been shown to serve as reservoir host of various viral agents including coronaviruses. They have also been associated with the novel coronavirus SARS-CoV-2. This has made them an all important agent for CoV evolution and transmission. Our objective in this study was to investigate the dispersal, phylogenomics and evolution of betacoronavirus (ßCoV) among African bats. We retrieved sequence data from established databases such as GenBank and Virus Pathogen Resource, covering the partial RNA dependent RNA polymerase (RdRP) gene of bat coronaviruses from eight African, three Asian, five European, two South American countries and Australia. We analyzed for phylogeographic information relating to genetic diversity and evolutionary dynamics. Our study revealed that majority of the African strains fell within Norbecovirus subgenera, with an evolutionary rate of 1.301 × 10-3, HPD (1.064 × 10-3-1.434 × 10-3) subs/site/year. The African strains diversified into three main subgenera, Norbecovirus, Hibecovirus and Merbecovirus. The time to most common recent ancestor for Norbecovirus strains was 1973, and 2007, for the African Merbecovirus strains. There was evidence of inter species transmission of Norbecovirus among bats in Cameroun and DRC. Phlylogeography showed that there were inter-continental spread of Bt-CoV from Europe, China and Hong Kong into Central and Southern Africa, highlighting the possibility of long distance transmission. Our study has elucidated the possible evolutionary origins of ßCoV among African bats; we therefore advocate for broader studies of whole genome sequences of BtCoV to further understand the drivers for their emergence and zoonotic spillovers into human population.

In Silico Screening and Analysis of Broad-Spectrum Molecular Targets and Lead Compounds for Diarrhea Therapy.

Diarrhoeal disease kills about 1.5 million human beings per year across the continents. The enterotoxigenic Escherichia coli (ETEC) pathotype has been noted as a major cause of diarrheal disease in human and livestock. The aim of this study is to identify broad-spectrum molecular targets in bacteria and broad-spectrum lead compounds (functional inhibitors) with high efficacy and no significant adverse implication on human systems, in relevance to diarrhea therapy through computational approaches which include phylogenetics, target prediction, molecular docking, and molecular flexibility dynamic simulations. Three molecular target genes, murA, dxr, and DnaE, which code for uridine diphosphate-N-acetylglucosamine-1-carboxyvinyltransferase, 1-deoxy-D-xylulose-5-phosphate reductoisomerase, and deoxyribonucleic acid polymerase III alpha subunit, respectively, were found to be highly conserved in 7 diarrhea-causing microbes. In addition, 21 potential compounds identified showed varied degree of affinity to these enzymes. At free energy cutoff of -8.0 kcal/mol, the highest effective molecular target was DNA polymerase III alpha subunit (PDB ID: 4JOM) followed by UDP-N-acetylglucosamine-1-carboxyvinyltransferase (PDB ID: 5UJS), and 1-deoxy-D-xylulose-5-phosphate reductoisomerase (PDB ID: 1ONN), while the highest effective lead compound was N-coeleneterazine followed by amphotericin B, MMV010576, MMV687800, MMV028694, azithromycin, and diphenoxylate. The flexibility dynamics of DNA polymerase III alpha subunit unraveled the atomic fluctuation which potentially implicated Asp593 as unstable active site amino acid residue. In conclusion, bacteria DnaE gene or its protein is a highly promising molecular target for the next generation of antibacterial drugs of the class of N-coeleneterazine.