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The production of fermentable sugars from lignocellulosic biomass is achieved by the synergistic action of a group of enzymes called cellulases. Cellulose is a long chain of chemically linked glucoses by β-1,4 bonds. The enzyme β-1,4-endoglucanase is the first cellulase involved in the degradation, breaking the bond of the amorphous regions. A β-1,4-endoglucanase enzyme with high activity was obtained from a Bacillus subtilis strain isolated from wastewater of a pulp and paper mill. Sequencing and bioinformatic analysis showed that the gene amplified by PCR consisting of 1407 nucleotides and coding for a β-1,4-endoglucanase enzyme of approximately 55 kDa. The open reading frame (ORF) encoding the mature endoglucanase (eglS) was successfully inserted in a modified cloning plasmid (pITD03) and into the pYD1 plasmid used for its expression in yeast. Carboxymethylcellulose (CMC) plate assay, SDS-PAGE, and zymogram confirmed the production and secretion by the transformed E. coli BL21-SI strain of a 39 kDa β-1,4-endoglucanase consistent with the catalytic domain without the cellulose-binding module (CBM). The results showed that the truncated β-1,4-endoglucanase had higher activity and stability. • A strain of Bacillus subtilis with endoglucanase activity was isolated from the wastewater of a pulp and paper mill. • The endoglucanase gene was inserted into a modified plasmid (E. coli) and into pYD1 (S. cerevisiae). • The endoglucanase in pYD1 is expressed with good activity in E. coli , being the first report of this finding. • A truncated recombinant endoglucanase is obtained and is very stable at pH (2-10) and temperature (30–55 °C). [ABSTRACT FROM AUTHOR]

Two new compounds namely [Zn(L1)phen] 3 1 and Ni(L1)phen(MeOH) 2 (L1 = 3, 5-dichlorosalicylaldehyde thiosemicarbazone) were synthesized by the slow evaporation method at room temperature. The structure of ligand L1 was determined using 1H NMR and 13C NMR spectra. X-ray single crystal diffraction analysis revealed that compounds 1 – 2 can form 3D supramolecular network structures through π ··· π stacking and hydrogen bonding interactions. The DFT calculation shows that the coordination of ligand and metal is in good agreement with the experimental results. Hirshfeld surface analysis revealed that H...H and Cl...H interactions were the predominant interactions in compounds 1 – 2. Energy framework analysis indicated that dispersion energy played a dominant role in the energy composition of compounds 1 – 2. The inhibitory effects of compounds 1 – 2 against Escherichia coli (E. coli) and Methicillin-resistant Staphylococcus aureus (MRSA) were tested using the paper disk diffusion method (1 : E. coli: 18 mm, MRSA: 17 mm, 2 : E. coli: 15 mm, MRSA: 16 mm). Ion releasing experiments were conducted to assess the ion release capacity of compounds 1 – 2 (Zn2+, 4 days, 38.33 µg/mL; Ni2+, 4 days, 29.12 µg/mL). Molecular docking demonstrated the interaction modes of compounds 1 – 2 with UDP- N -acetylenolpyruvoylglucosamine reductase (MurB) and dihydrofolate reductase (DHFR) in bacteria, involving hydrophobic, stacking, hydrogen bonding and halogen bonding interactions. The generation of reactive oxygen species (ROS) in bacteria under the presence of compounds 1 – 2 were evaluated using a fluorescent dye known as dichlorodihydrofluorescein diacetate (DCFH-DA). Potential antibacterial mechanisms of compounds 1 – 2 were proposed. [Display omitted] • Two new compounds [Zn(L1)phen] 3 1 and Ni(L1)phen(MeOH) 2 were synthesized under room temperature. • Compounds 1 – 2 were both extended into a 3D supermolecule network structure via π ··· π stacking and hydrogen bonding interactions. • Compounds 1 – 2 were both potential antibacterial bacterial for E. coli and MRSA (1 : E. coli: 18 mm, MRSA: 17 mm, 2 : E. coli: 15 mm, MRSA: 16 mm). • Molecular docking of protein and DNA for compounds 1 – 2 were investigated. • The potential antibacterial mechanism of compounds 1 – 2 was proposed via combining with theoretical calculation and experimental results. Two new compounds namely [Zn(L1)phen] 3 1 and Ni(L1)phen(MeOH) 2 (L1 = 3, 5-dichlorosalicylaldehyde thiosemicarbazone) were synthesized by the slow evaporation method at room temperature. The structure of ligand L1 was determined using 1H NMR and 13C NMR spectra. X-ray single crystal diffraction analysis revealed that compounds 1 – 2 can form 3D supramolecular network structures through π ··· π stacking and hydrogen bonding interactions. The DFT calculation shows that the coordination of ligand and metal is in good agreement with the experimental results. Hirshfeld surface analysis revealed that H...H and Cl...H interactions were the predominant interactions in compounds 1 – 2. Energy framework analysis indicated that dispersion energy played a dominant role in the energy composition of compounds 1 – 2. The inhibitory effects of compounds 1 – 2 against Escherichia coli (E. coli) and Methicillin-resistant Staphylococcus aureus (MRSA) were tested using the paper disk diffusion method (1 : E. coli: 18 mm, MRSA: 17 mm, 2 : E. coli: 15 mm, MRSA: 16 mm). Ion releasing experiments were conducted to assess the ion release capacity of compounds 1 – 2 (Zn2+, 4 days, 38.33 µg/mL; Ni2+, 4 days, 29.12 µg/mL). Molecular docking demonstrated the interaction modes of compounds 1 – 2 with UDP- N -acetylenolpyruvoylglucosamine reductase (MurB) and dihydrofolate reductase (DHFR) in bacteria, involving hydrophobic, stacking, hydrogen bonding and halogen bonding interactions. The generation of reactive oxygen species (ROS) in bacteria under the presence of compounds 1 – 2 were evaluated using a fluorescent dye known as dichlorodihydrofluorescein diacetate (DCFH-DA). Potential antibacterial mechanisms of compounds 1 – 2 were proposed. [ABSTRACT FROM AUTHOR]

The indiscriminate use of antimicrobials has led to the emergence of resistant bacteria, especially pathogenic strains of Escherichia coli , which are associated with diseases in animals and humans. The aim of the present study was to characterize E. coli isolates in calves with regards to the presence of virulence genes and investigate the resistance of the isolates to different antimicrobials. Between 2021 and 2023, 456 fecal samples were collected from calves in the Pantanal and Cerrado biomes of the state of Mato Grosso do Sul, Brazil. All samples were subjected to microbiological analysis and disc diffusion antibiogram testing. The polymerase chain reaction method was used to detect virulence genes. Bacterial growth was found in 451 of the 456 samples and biochemically identified as Escherichia coli. All 451 isolates (100 %) exhibited some phenotypic resistance to antimicrobials and 67.62 % exhibited multidrug resistance. The frequency of multidrug-resistant isolates in the Cerrado biome was significantly higher than that in the Pantanal biome (p = 0.0001). In the Cerrado , the most common pathotype was Shiga toxin-producing Escherichia coli (STEC) (28 %), followed by toxigenic Escherichia coli (ETEC) (11 %), enterohemorrhagic Escherichia coli (EHEC) (8 %) and enteropathogenic Escherichia coli (EPEC) (2 %). In most cases, the concomitant occurrence of pathotypes was more common, the most frequent of which were ETEC + STEC (33 %), ETEC + EHEC (15 %) and ETEC + EPEC (3 %). The STEC pathotype (30 %) was also found more frequently in the Pantanal , followed by EHEC (12 %), ETEC (9 %) and EPEC (6 %). The STEC pathotype had a significantly higher frequency of multidrug resistance (p = 0.0486) compared to the other pathotypes identified. The frequency of resistance was lower in strains from the Pantanal biome compared to those from the Cerrado biome. Although some factors are discussed in this paper, it is necessary to clarify the reasons for this difference and the possible impacts of these findings on both animal and human health in the region. • Multi-resistant bacteria in cattle in the Cerrado and Pantanal biomes of Brazil. • Antimicrobial multiresistance of E. coli pathotypes isolated from calf feces. • Domestic animals and humans, exchange of pathogens between different species. [ABSTRACT FROM AUTHOR]

Leafy greens, especially lettuce, are repeatedly linked to foodborne outbreaks. This paper studied the susceptibility of different leafy greens to human pathogens. Five commonly consumed leafy greens, including romaine lettuce, green-leaf lettuce, baby spinach, kale, and collard, were selected by their outbreak frequencies. The behavior of E. coli O157:H7 87-23 on intact leaf surfaces and in their lysates was investigated. Bacterial attachment was positively correlated with leaf surface roughness and affected by the epicuticular wax composition. At room temperature, E. coli O157:H7 had the best growth potentials on romaine and green-leaf lettuce surfaces. The bacterial growth was positively correlated with stomata size and affected by epicuticular wax compositions. At 37 °C, E. coli O157:H7 87-23 was largely inhibited by spinach and collard lysates, and it became undetectable in kale lysate after 24 h of incubation. Kale and collard lysates also delayed or partially inhibited the bacterial growth in TSB and lettuce lysate at 37 °C, and they sharply reduced the E. coli O157:H7 population on green leaf lettuce at 4 °C. In summary, the susceptibility of leafy greens to E. coli O157:H7 is determined by a produce-specific combination of physiochemical properties and temperature. • Lysate will not affect E. coli O157:H7 growth and survival on intact leaves. • E. coli 's survival on leaves depends on produce-specific traits and temperature. • Spinach, collard, kale lysates are natural antimicrobials against E. coli O157:H7. • At 37 °C, kale lysate inactivated E. coli O157:H7 in pure culture within 24h. • Kale and collard lysates reduced E. coli population on the lettuce surface at 4 °C. [ABSTRACT FROM AUTHOR]

Nanomaterials containing tungsten (TNMs), characterized by diverse nanostructures had been extensively used in biomedical sector. Despite numerous reports focusing on TNM applications in specific biomedical areas, there is a noticeable absence of comprehensive studies that focused on detailed characterization of nanomaterials along with their biological applications. The present work described the structural, morphological, and antimicrobial properties of tungsten oxide (WO 3) nanoparticles coated by antibiotics (nanobiotics), and their application on single and mixed bacterial culture. The nanobiotics included in this study were WO 3 coated with ampicillin (W+A), WO 3 coated with penicillin (P+W), and WO 3 coated with ciprofloxacin (C+W). Techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray spectroscopy (EDX), Fourier transforms infrared spectroscopy (FTIR), Rrman spectroscopy, and UV–visible spectroscopy were used to characterize synthesized nanoparticles. The minimum inhibitory concentration of C+W nanobiotic against S. aureus , E. coli , and mixed culture (S. aureus + E. coli) was lower than that of P+W and A+W. The impact of incubation period showed significant differences for each of nanobiotic against S. aureus , E. coli , and mixed culture. However, there were also non-significant differences among incubation periods for antibacterial activity of nanobiotics. It was pertinent to note that percentage variation in susceptibility of S. aureus with respect to mixed culture remained higher as compared to E. coli, indicating it stronger candidate imposing resistance. This paper thus suggested the strategy of coating of antibiotics with with WO 3 nanoparticles as an ideal combination for resistance modulation against single and mixed culture bacteria. [Display omitted] • Tungsten oxide nanoparticles successfully coupled with antibiotics. • Nanoparticles coupled antibiotics revealed appealing characteristics. • Ciprofloxacin coupling proved to be significant antibacterial compared to others. • S. aureus showed highest sensitivity compared to E. coli & mixed culture infection. • E. coli showed higher resistance than to S. aureus in mixed culture infection. [ABSTRACT FROM AUTHOR]

The SulA protein of Escherichia coli and related bacteria interacts directly with FtsZ, blocking cell division by disrupting Z-ring formation, yet the precise mechanism remains not fully understood. Previous demonstrations of Pseudomonas aeruginosa SulA's dimerization capability were confined to X-ray crystallography and lacked confirmation under in vivo conditions. Additionally, uncertainty persisted regarding the dimerization potential of E. coli's SulA protein. This paper employs a bacterial two-hybrid system to establish that both P. aeruginosa and E. coli SulA proteins indeed possess the capacity for dimerization. [Display omitted] • SulA proteins from E. coli and P. aeruginosa are capable of dimerization. • N-terminal fusion of Venus to E. coli SulA impairs dimerization of SulA. • SulA proteins from E. coli and P. aeruginosa demonstrate similar dimerization interfaces. [ABSTRACT FROM AUTHOR]