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According to the CDC, there are more than 2.8 million antibiotic resistant infections occurring in the United States each year, and more than 35,000 people die as a result (CDC 2019). Furthermore, the CDC classifies a group of bacteria known as ESKAPE pathogens as six emerging antibiotic-resistant pathogens that are difficult to eradicate with current antibiotics. Our study aims to identify and characterize soil-derived microorganisms with the potential to produce antimicrobial compounds effective against safe relatives of ESKAPE pathogens, with the goal of translating these findings to combat their pathogenic counterparts. We hypothesize that bacteria identified from the soil will inhibit the growth of the following nosocomial associated safe relatives Bacillus subtilis for E. faecium, Staphylococcus epidermidis for S. aureus, Escherichia coli for Klebsiella pneumoniae, Acinetobacter baylyi for A. baumannii, Pseudomonas putida for P. aeruginosa, and Enterobacter aerogenes for Enterobacter species. To test our hypothesis, soil samples were collected from Fayetteville State University (FSU) campus and serially diluted onto LB agar plates. Sixty-three distinct colonies were isolated and screened against non-pathogenic ESKAPE safe relatives. Of the 63 Fayetteville State University soil isolates (FSIs) screened, 12 (19%) exhibited antimicrobial activity against at least one of the six ESKAPE safe relatives, with all 12 inhibiting Acinetobacter baylyi and only FSI 15 demonstrating broad-spectrum inhibition. Characterization assays revealed that 11 of the 12 isolates were Gram-negative, catalase-positive, and motile; the single Gram-positive isolate (FSI 4) was catalase-negative and non-motile. All isolates displayed resistance to penicillin, while most remained susceptible to tetracycline and ciprofloxacin. These findings support our hypothesis that soil-derived bacteria can produce putative antimicrobial compounds effective against non-pathogenic ESKAPE safe relatives. This study underscores the potential of soil microbiota on the campus of Fayetteville State University as a source of novel antimicrobial agents capable of inhibiting antibiotic resistant ESKAPE pathogens and warrant further investigation into their therapeutic potential 

The evolutionary histories of many polyploid plant species are difficult to resolve due to a complex interplay of hybridization, incomplete lineage sorting, and missing diploid progenitors. In the case of octoploid strawberry with four subgenomes designated ABCD, the identities of the diploid progenitors for subgenomes C and D have been subject to much debate. By integrating new sequencing data from North American diploids with reticulate phylogeny and admixture analyses, we uncovered introgression from an extinct or unsampled species in the clade ofFragaria viridis,Fragaria nipponica, andFragaria nilgerrensisinto the donor of subgenome A of octoploidFragariaprior to its divergence fromF. vescasubsp. bracteata. We also detected an introgression event fromF. iinumaeinto an ancestor ofF. nipponicaandF. nilgerrensis.Using an LTR-age-distribution-based approach, we estimate that the octoploid and its intermediate hexaploid and tetraploid ancestors emerged approximately 0.8, 2, and 3 million years ago, respectively. These results provide an explanation for previous reports ofF. viridisandF. nipponicaas donors of the C and D subgenomes and suggest a greater role than previously thought for homoploid hybridization in the diploid progenitors of octoploid strawberry. The integrated set of approaches used here can help advance polyploid genome analysis in other species where hybridization and incomplete lineage sorting obscure evolutionary relationships. 

We consider a system of two balance laws of Keyfitz–Kranzer type with varying generalized Chaplygin gas, which exhibits negative pressure and is a product of a function of time and the inverse of a power of the density. The Chaplygin gas is a fluid designed to accommodate measurements for the early universe and late-time universal expansion while obeying the pressure–density–time relation. We produce an explanation and description of the non-self-similar Riemann solutions, including the non-classical singular solutions. We also find that due to a direct dependence on time, a change in the regions allowing for combinations of classical and non-classical singular solutions occurs; therefore, a Riemann solution can have different solutions over several time intervals. Our findings are confirmed numerically using the Local Lax–Friedrichs scheme.