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Increasing soil salinity, exacerbated by climate change, threatens seed germination and crop growth, causing significant agricultural losses. Using bioinoculants based on halotolerant plant growth-promoting endophytes (PGPEs) in modern agriculture is the most promising and sustainable method for supporting plant growth under salt-stress conditions. Our study evaluated the efficacy of Pseudomonas stutzeri ISE12, an endophyte derived from the extreme halophyte Salicornia europaea , in enhancing the salinity tolerance of sorghum (Sorghum bicolor L.). We hypothesized that P. stutzeri ISE12 would improve sorghum salt tolerance to salinity, with the extent of the increase in tolerance depending on the genotype's sensitivity to salt stress. Experiments were conducted for two sorghum genotypes differing in salinity tolerance (Pegah - salt tolerant, and Payam - salt sensitive), which were inoculated with a selected bacterium at different salinity concentrations (0, 100, 150, and 200 mM NaCl). For germination, we measured germination percentage and index, mean germination time, vigor, shoot and root length of seedlings, and fresh and dry weight. In pot experiments, we assessed the number of leaves, leaf area, specific leaf area, leaf weight ratio, relative root weight, plantlet shoot and root length, fresh and dry weight, proline and hydrogen peroxide concentrations, and peroxidase enzyme activity. Our study demonstrated that inoculation significantly enhanced germination and growth for both sorghum genotypes. The salinity-sensitive genotype (Payam) responded better to bacterial inoculation during germination and early seedling growth stages, showing approximately 1.4 to 1.8 times greater improvement than the salinity-tolerant genotype (Pegah). Payam also displayed better performance at the plantlet growth stage, between 1.1 and 2.6 times higher than Pegah. Furthermore, inoculation significantly reduced hydrogen peroxide, peroxidase activity, and proline levels in both sorghum genotypes. These reductions were notably more pronounced in Payam, with up to 1.5, 1.3, and 1.5 times greater reductions than in Pegah. These results highlight the efficacy of P. stutzeri ISE12 in alleviating oxidative stress and reducing energy expenditure on defense mechanisms in sorghum, particularly benefiting salt-sensitive genotypes. Our findings highlight the potential of the bacterial endophyte P. stutzeri ISE12 as a valuable bioinoculant to promote sorghum growth under saline conditions. [ABSTRACT FROM AUTHOR]

Increasing soil salinity, exacerbated by climate change, threatens seed germination and crop growth, causing significant agricultural losses. Using bioinoculants based on halotolerant plant growth-promoting endophytes (PGPEs) in modern agriculture is the most promising and sustainable method for supporting plant growth under salt-stress conditions. Our study evaluated the efficacy of Pseudomonas stutzeri ISE12, an endophyte derived from the extreme halophyte Salicornia europaea, in enhancing the salinity tolerance of sorghum (Sorghum bicolor L.). We hypothesized that P. stutzeri ISE12 would improve sorghum salt tolerance to salinity, with the extent of the increase in tolerance depending on the genotype's sensitivity to salt stress. Experiments were conducted for two sorghum genotypes differing in salinity tolerance (Pegah - salt tolerant, and Payam - salt sensitive), which were inoculated with a selected bacterium at different salinity concentrations (0, 100, 150, and 200mMNaCl). For germination, we measured germination percentage and index, mean germination time, vigor, shoot and root length of seedlings, and fresh and dry weight. In pot experiments, we assessed the number of leaves, leaf area, specific leaf area, leaf weight ratio, relative root weight, plantlet shoot and root length, fresh and dry weight, proline and hydrogen peroxide concentrations, and peroxidase enzyme activity. Our study demonstrated that inoculation significantly enhanced germination and growth for both sorghum genotypes. The salinity-sensitive genotype (Payam) responded better to bacterial inoculation during germination and early seedling growth stages, showing approximately 1.4 to 1.8 times greater improvement than the salinity-tolerant genotype (Pegah). Payam also displayed better performance at the plantlet growth stage, between 1.1 and 2.6 times higher than Pegah. Furthermore, inoculation significantly reduced hydrogen peroxide, peroxidase activity, and proline levels in both sorghum genotypes. These reductions were notably more pronounced in Payam, with up to 1.5, 1.3, and 1.5 times greater reductions than in Pegah. These results highlight the efficacy of P. stutzeri ISE12 in alleviating oxidative stress and reducing energy expenditure on defense mechanisms in sorghum, particularly benefiting salt-sensitive genotypes. Our findings highlight the potential of the bacterial endophyte P. stutzeri ISE12 as a valuable bioinoculant to promote sorghum growth under saline conditions. [ABSTRACT FROM AUTHOR]

Adenylate kinases (AK) play a pivotal role in the regulation of cellular energy. The aim of our work was to achieve the overproduction and purification of AKs from two groups of bacteria and to determine, for the first time, the comprehensive biochemical and kinetic properties of adenylate kinase from Gram-negative Aquifex aeolicus (A[K.sub.aq]) and Gram-positive Geobacillus stearothermophilus (A[K.sub.st]). Therefore we determined [K.sub.M] and [V.sub.max] values, and the effects of temperature, pH, metal ions, donors of the phosphate groups and inhibitor A[p.sub.5]A for both thermophilic AKs. The kinetic studies indicate that both AKs exhibit significantly higher affinity for substrates with the pyrophosphate group than for adenosine monophosphate. AK activation by [Mg.sup.2+] and [Mn.sup.(2)+] revealed that both ions are efficient in the synthesis of adenosine diphosphate and adenosine triphosphate; however, [Mn.sub.(2)+] ions at 0.2-2.0 mmol/L concentration were more efficient in the activation of the ATP synthesis than [Mg.sup.2+] ions. Our research demonstrates that zinc ions inhibit the activity of enzymes in both directions, while A[p.sub.5]Aat a concentration of 10 [micro]mol/L and 50 [micro]mol/L inhibited both enzymes with a different efficiency. Sigmoid-like kinetics were detected at high ATP concentrations not balanced by [Mg.sup.(2)+], suggesting the allosteric effect of ATP for both bacterial AKs. Key words: adenylate kinase (AK), kinetic studies, nucleotide, Aquifex aeolicus, Geobacillus stearothermophilus. Les adenylate kinases (AK) jouent un role essentiel dans la regulation de l'energie cellulaire. L'objectif de ces travaux etait de parvenir a la surproduction et a la purification des AK de deux groupes de bacteries et, pour la premiere fois, de determiner les proprietes biochimiques et cinetiques completes de l'adenylate kinase d'Aquifex aeolicus (A[K.sub.aq])a Gram negatif et de Geobacillus stearothermophilus (A[K.sub.st]) a Gram positif. Les auteurs ont donc determine les valeurs de [K.sub.M] et de [V.sub.max], ainsi que les effets de la temperature, du pH, des ions metalliques, des donneurs de groupes phosphate et de l'inhibiteur A[p.sub.5]A pour les deux AK thermophiles. Les etudes cinetiques indiquent que les deux AKs presentent une affinite significativement plus elevee pour le groupe pyrophosphate que pour l'AMP en tant que substrats. L'activation des AK par le [Mg.sup.2+] et le [Mn.sup.(2)+] revele que les deux ions sont efficaces dans la synthese de l'ADP et de l'ATP; toutefois, les ions [Mn.sup.(2)+] aune concentration de 0,2-2,0 mmol/Letaient plus efficaces dans l'activation de la syn-thesedel'ATP que les ions [Mg.sup.(2)+]. Ces recherches demontrent que les ions zinc inhibent l'activite des enzymes dans les deux directions, tandis que l'A[p.sub.5]A a une concentration de 10 [micro]mol/L et 50 [micro]mol/L inhibait les deux enzymes avec une efficacite differente. Une cinetique de type sigmoide a ete detectee a des concentrations elevees d'ATP non equilibrees par le [Mg.sup.(2)+], ce qui suggere un effet allosterique de l'ATP pour les deux AK bacteriennes. [Traduit par la Redaction] Mots-cles: adenylate kinase (AK), etudes cinetiques, nucleotide, Aquifex aeolicus, Geobacillus stearothermophilus., Introduction Adenylate kinases (AKs, EC 2.7.4.3) are low-molecular-weight phosphotransferases (21-25 kDa) catalysing transphosphorylation reactions according to the equations (Krishnamurthy 2005): [Mg.sup.(2+]) : ATP + AMP [right arrow] [Mg.sup.2+] : ADP [...]

The pace of life is accelerating, so we are seeking ways to optimize the shelf life of products. To achieve this goal, the microbiological quality of rabbit meat was assessed at 7, 14, and 21 days under refrigerated conditions, utilizing two storage methods, modified atmosphere packaging (MAP) and vacuum packaging (VAC). Maintaining high levels of hygiene is critical not only during slaughter but also during subsequent technological processes and meat storage. The research concluded that the MAP method was more effective at extending the shelf‐life of fresh rabbit meat than the VAC method. Additionally, increasing the CO2 concentrations in meat significantly decreased the Pseudomonas bacteria population (after 14 and 21 days of storage). Conversely, the gaseous mixture containing 70% O2 significantly decreased the Enterobacteriaceae population in the sample after 21 days of storage. Moreover, the MAP storage method considerably impeded microbial growth, particularly the total yeast and mold count, lactic acid bacteria count, and Pseudomonas spp. count. This study's findings demonstrate that rabbit meat can be stored for 21 days in a modified atmosphere containing appropriate concentrations of gases such as gaseous carbon dioxide and oxygen. [ABSTRACT FROM AUTHOR]

A total of 12 farmed fallow deer bucks and 12 does aged 31-32 months were included in a study on the effect of storage in vacuum packaging on the functionality of venison of the Semimembranosus muscle. All the analyzed meat quality traits were not affected by sex. The storage of meat in vacuum led to: an increase of pH (by 0.13 units; P = 0.001), L* (by 1.85 units; P = 0.002), a* (by 1.15 units; P = 0.013) and chroma (by 1.16 units; P = 0.016), a decrease of free water (by 6.62 percentage points (p.p.); P = 0.001) and water-holding capacity (cm2) (by 29.61%; P = 0.001), and the increase of dry matter content (by 0.67 p.p.; P = 0.001). The results indicate that the chilled storage of venison caused the stabilization of pH and color, improvement of water-holding capacity, with no negative effect on the proximate chemical composition. The quality of deer meat obtained from does and bucks was similar. [ABSTRACT FROM AUTHOR]

In this investigation, we detail the synthesis of silver nanoparticles (AgNPs) via a precise chemical vacuum deposition (CVD) methodology, aimed at augmenting the analytical performance of laser desorption/ionization mass spectrometry (LDI-MS) for the detection of low-molecular-weight analytes. Employing a precursor supply rate of 0.0014 mg/s facilitated the formation of uniformly dispersed AgNPs, characterized by SEM and AFM to have an average diameter of 33.5 ± 1.5 nm and a surface roughness (Ra) of 11.8 nm, indicative of their homogeneous coverage and spherical morphology. XPS and SEM-EDX analyses confirmed the metallic silver composition of the nanoparticles with Ag peak splitting, reflecting the successful synthesis of metallic Ag. Comparative analytical evaluation with traditional MALDI matrices revealed that AgNPs significantly reduce signal suppression, thereby enhancing the sensitivity and specificity of LDI-MS for low-molecular-weight compounds such as triglycerides, saccharides, amino acids, and carboxylic acids. Notably, the application of AgNPs demonstrated a superior linear response for triglyceride signals with regression coefficients surpassing 0.99, markedly outperforming conventional matrices. The study further extends into quantitative analysis through nanoparticle-based laser desorption/ionization (NALDI), where AgNPs exhibited enhanced ionization efficiency, characterized by substantially lower limits of detection (LOD) and quantification (LOQ) for tested standards. Particular attention was paid to lipids with a detailed examination of their fragmentation pathways. These results highlight the significant potential of AgNPs synthesized via CVD to transform the analytical detection and quantification of low-molecular-weight compounds using NALDI. This approach offers a promising avenue for expanding the scope of analytical applications in mass spectrometry and introducing innovative methodologies for enhanced precision and sensitivity. [ABSTRACT FROM AUTHOR]

A method of purifying cyclododecyl 2,4-dihydroxybenzoate as a potential replacement template molecule for preparation of molecularly-imprinted polymers for isolation of zearalenone in urine was developed. Full physicochemical characteristics of cyclododecyl 2,4-dihydroxybenzoate for the first time included crystallographic analysis and molecular modelling, which made possible the determination of the similarity between the cyclododecyl 2,4-dihydroxybenzoate and zearalenone molecules. The obtained molecularly-imprinted polymers show very high in vitro selectivity towards zearalenone due to specific interactions (e.g., hydrogen bonding, molecular recognition interaction). The achieved extraction recovery exceeds 94% at the tested concentration levels (20–500 ng·mL−1) with a relative standard deviation below 2%. Immunosorbents were found to have lower recoveries (below 92.5%) and RSD value between 2 and 4% for higher concentrations of the studied substance (400 ng·mL−1). [ABSTRACT FROM AUTHOR]

The lipid composition of bacterial membranes is pivotal in regulating bacterial physiology, pathogenicity, and interactions with hosts. This study presents a comprehensive analysis of bacterial membrane lipid profiles across diverse Gram-positive and Gram-negative species. Utilizing matrix-assisted laser desorption/ionization (MALDI) in conjunction with advanced chemometric tools, we investigate the influence of environmental factors, isolation sources, and host metabolism on bacterial lipid profiles. Our findings unveil significant variations in lipid composition attributed to factors such as carbon/energy availability and exposure to chemicals, including antibiotics. Moreover, we identify distinct lipidomic signatures associated with pathogenic and probiotic bacterial strains, shedding light on their functional properties and metabolic pathways. Notably, bacterial strains isolated from clinical samples exhibit unique lipid profiles influenced by host metabolic dysregulation, particularly evident in conditions such as diabetic foot infections. These results deepen our understanding of the intricate mechanisms governing bacterial membrane lipid biology and hold promise for informing the development of innovative therapeutic and biotechnological strategies., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

A method of purifying cyclododecyl 2,4-dihydroxybenzoate as a potential replacement template molecule for preparation of molecularly-imprinted polymers for isolation of zearalenone in urine was developed. Full physicochemical characteristics of cyclododecyl 2,4-dihydroxybenzoate for the first time included crystallographic analysis and molecular modelling, which made possible the determination of the similarity between the cyclododecyl 2,4-dihydroxybenzoate and zearalenone molecules. The obtained molecularly-imprinted polymers show very high in vitro selectivity towards zearalenone due to specific interactions (e.g., hydrogen bonding, molecular recognition interaction). The achieved extraction recovery exceeds 94% at the tested concentration levels (20⁻500 ng·mL -1 ) with a relative standard deviation below 2%. Immunosorbents were found to have lower recoveries (below 92.5%) and RSD value between 2 and 4% for higher concentrations of the studied substance (400 ng·mL -1 ).