Pantoea Agglomerans Research Articles

Wpływ metody inokulacji roślin kukurydzy patogenami bakteryjnymi na powstawanie i rozwój objawów chorobowych

The basis of phytopathological diagnostics are Koch’s postulates, the fulfillment of which allows determining whether the examined microorganism is the cause of a given disease. The third of these postulates specifies that inoculation of a healthy host plant with a pure culture of the putative pathogen must result in the induction of disease symptoms similar or the same to those occurring in natural con¬ditions. To meet Koch’s third postulate, a pathogenicity test result is required, and incorrect interpretation may lead to rejection of cor¬rect results. Many years of research on bacteriosis of crop plants, including corn, have shown that the symptoms of the disease resulting from inoculation with the tested strain of bacteria may vary, depending on the inoculation method used and the incubation conditions of the inoculated plants. The conducted research determined the impact of various methods of inoculating corn plants with selected strains of pathogenic bacteria isolated from diseased corn plants on the occurrence and development of disease symptoms. These strains belonged to the species Pectobacterium carotovorum subsp. carotovorum, Dickeya zeae, Pantoea ananatis, Pantoea agglomerans and Enterobacter cloaceae subsp. dissolvens. It was observed that the symptoms of the disease caused by the inoculation methods used dif¬fer from the symptoms observed in natural conditions. Moreover, regardless of the species affiliation of the tested bacterial strains, the observed symptoms were similar within a given inoculation method. Also, regardless of the species affiliation of the tested strain, incuba¬tion of inoculated plants in a culture chamber with optimal conditions for the development of the disease resulted in the acceleration of symptoms and disease development.

First Report of Pantoea agglomerans Causing Leaf Blight on Schisandra chinensis in China.

Schisandra chinensis (Turcz.) Baill is a perennial liana, which is widely cultivated and used in China. In August 2022, Schisandra chinensis leaves with small light brown spots were found on plants growing in Fusong (127°28'E, 42°33'N) of China. There was 15% disease incidence and 50% disease severity of Schisandra chinensis in 2-ha fields of S. chinensis. As the disease progressed, the spots become darker and form round or irregular concentric circles. Leaves with brown spot symptoms were collected from the field. Leaf pieces (5 mm × 5 mm) were excised from lesion margins, surface disinfected with 75% ethanol for 1 min, followed by 1.5% sodium hypochlorite for 3 min, and incubated on Luria Bertani (LB) solid medium at 28°C for 24 hours. Eight cultures were isolated, and representative single colony (XWWZH) was selected from the pure cultures according to colony characteristics for observation The purified colonies were round, yellow, and slimy, cells were straight rod-shaped (0.40 to 0.52 × 1.12 to 1.69 µm) were observed. The isolate was Gram negative. It was positive for methyl red reaction, lysine decarboxylase reaction, gelatin hydrolysis reactionand sucrose utilization. It was negative for indole reaction and produced H2S. The bacterium was preliminarily identified as Pantoea agglomerans based on morphological and biochemical tests (Baird et al. 2007). The 16S rDNA and a portion of rpoB of strain XWWZH were amplified and sequenced. The sequences were submitted to GenBank. (Accession OP763753 and OQ813505, respectively). Phylogenetic trees were constructed based on the 16S rDNA and rpoB gene sequences. The sequences of strain XWWZH clustered with strains P. agglomerans deposited in GenBank. The pathogenicity was verified with non-wounded S. chinensis seedlings by punching holes with sterile needles and injecting a solution of 1 × 108 CFU/ml solution. Sterile ddH2O was injected in the control experiment. The inoculated seedlings were incubated in a greenhouse at 25°C with a relative humidity of 65 to 70%. Five to eight days after inoculation, inoculated leaves, exhibited symptoms which were morphologically identical to those of the originally infected leaves whereas control plants remained asymptomatic. The pathogenicity assays were repeated twice with the same results. The re-isolated pathogen had the same morphology and DNA sequences as the original isolate obtained from the field samples, completing Koch's postulates. Strains of P. agglomerans have been reported to severely infect many plants (Ren et al.2008; Lee et al. 2010; Yang et al. 2011; Guo et al. 2019; Gao et al, 2022), but to the best of our knowledge, this is the first report of a strain of P. agglomerans causing leaf blight on Schisandra chinensis in China. The identification of leaf blight caused by P. agglomerans will enable farmers to prevent and manage it ahead of time to reduce losses.

Osmotolerant plant growth promoting bacteria mitigate adverse effects of drought stress on wheat growth.

Drought stress represents a major constraint with significant impacts on wheat crop globally. The use of plant growth-promoting bacteria (PGPB) has emerged as a promising strategy to alleviate the detrimental impacts of water stress and enhance plant development. We investigated 24 strains from diverse ecosystems, assessed for PGP traits and tolerance ability to abiotic stresses (drought, salinity, temperature, pH, heavy metals, pollutants, herbicides, and fungicides). The most effective bacterial strains Providencia vermicola ME1, Pantoea agglomerans Pa, Pseudomonas knackmussi MR6, and Bacillus sp D13 were chosen. Furthermore, these strains exhibited PGP activities under osmotic stress (0, 10, 20, and 30% PEG-6000). The impact of these osmotolerant PGPBs on wheat (Triticum durum L.) growth under drought stress was assessed at two plant growth stages. In an in vitro wheat seed germination experiment, bacterial inoculation significantly enhanced germination parameters. In pot experiments, the potential of these bacteria was evaluated in wheat plants under three treatments: Well-watered (100% field capacity), moderate stress (50% FC), and severe stress (25% FC). Results showed a significant decline in wheat growth parameters under increasing water stress for uninoculated seedlings. In contrast, bacterial inoculation mitigated these adverse effects, significantly improving morphological parameters and chlorophyll pigment contents under the stress conditions. While malondialdehyde (lipid peroxidation) and proline contents increased significantly with drought intensity, they decreased after bacterial inoculation. The antioxidant enzyme activities (GPX, CAT, and SOD) in plants decreased after bacterial inoculation. The increased root colonization capacity observed under water stress was attributed to their ability to favorable adaptations in a stressful environment. This study highlighted the potential of selected PGPB to alleviate water stress effects on wheat, promoting practical applications aimed at enhancing crop resilience under conditions of water shortage.

BACTERIAL CONJUNCTIVITIS IN HADHRAMOUT GOVERNORATE-YEMEN

Bacterial conjunctivitis is one of the most commonly encountered eye complications in medicine, particularly in developing nations. In Hadhramout Governorate-Yemen, there is no data about bacterial conjunctivitis among patients. The present study aimed to determine the prevalence rate of bacterial conjunctivitis among patients seeking hospitals in Hadhramout Governorate, Yemen. A total of 1722 eye swabs were collected from patients attending different Hadhramout hospitals over a period of April to December 2018. The isolation and identification of bacteria are performed using standard bacteriological procedures. In addition, structured questionnaires were used to gather data from patients. Out of 1722 eye swabs, 198 (11.49%) were positive for bacterial conjunctivitis, while 1524 (88.5%) were negative. The high prevalence rate of infection was among female participants and the age group between 31 and 40 years, at 15.25% and 29.29%, respectively. In addition, the prevalence of gram-positive bacteria was significantly greater among study patients than gram-negative bacteria (58.59% vs. 41.41%). The most predominant Gram-positive bacteria were Staphylococcus aureus (26.26%), followed by Streptococci pneumoniae (17.18%), Alpha-hemolytic Streptococci (8.08%), and Staphylococcus epidermidis (7.07%). Whereas the gram-negative bacteria were Pseudomonas aeruginosa (12.1%), followed by Moraxella catarrhalis (10.1%), Haemophilus influenza (7.07%), Klebsiella sp. (6.06%), Enterobacter agglomerans (4.04%), and Neisseria gonorrhoeae (2.02%). Additionally, the majority of study patients suffered from red eyes (100%), tearing eyes (93.93%), itching (90.9%), painful eyes (87.87%), purulent eyes (56.56%), and eye discharge (38.38%). The prevalence rate of bacterial conjunctivitis among patients in Hadhramout, Yemen, is relatively low compared with international investigations. Further investigation is required to assess and identify the antibiotic resistance to these agents that cause conjunctivitis.

Identification of bacteria species among Enterobacteriaceae found in confectionery cakes

The goal of this research was to identify which Enterobacteriaceae species are present in cakes from confectionery establishments and whether these are species that can be considered pathogenic for humans and what their harmful impact on human health could be. The sampling of confectionery cakes was carried out in the area of the City of Zagreb, and the samples were analysed for the presence of Enterobacteriaceae in accordance with the HRN ISO 21528-2:2017 standard. In cases where the samples contained the number of Enterobacteriaceae greater than 102 CFU/g, the MALDI-TOF method was used to identify individual species of enterobacteria. The results of the analyses determined the presence of 10 Enterobacteriaceae species: Enterobacter kobei, Enterobacter cloacae, Pantoea agglomerans, Serratia liquefaciens, Enterobacter asburiae, Klebsiella oxytoca, Buttiauxella gaviniae, Buttiauxella warmboldiae, Raoultella and Cedecea neteri. All species of Enterobacteriaceae determined in this research, according to the literature, were previously isolated from food or water, and all species except Buttiauxella warmboldiae were isolated from humans and the environment. However, for none of the species of Enterobacteriaceae determined in this research a literature reference to support food as a vehicle in case of human illness was found.

MICROFLORA AND PLANT PATHOGENIC FUNGI AFFECTING BACTERIA IN GRAPE PLANTATIONS IN UZBEKISTAN

In the presented study, isolation of bacterial strains, viz., Pantoea agglomerans, Priestia megaterium and phytopathogenic micromycetes that cause damage and eventually death of grape crops, came from a 10 to 15-year-old vine plantation. A Pantoea agglomerans gram-negative bacillus facultative and anaerobic bacterium strain achieved isolation from grape plants, with its morphological characteristics studied. Bacterial strains with antifungal activities against phytopathogenic micromycetes succeeded in their identification. Bacterial isolates collected from the vines underwent screening for their growth properties. It was apparent that Pantoea agglomerans actively grew wheat coleoptiles by 2.6 mm and maize coleoptiles by 2.3 mm compared with the control. Observable evidence also showed that sorghum coleoptile actively grew by 1.7 mm compared with the control treatment by 2.9 mm. The 26 Aspergillus sp., 23 Penicillium sp., 25 Fusarium sp., 30 Alternaria sp., and five Curvularia sp. phytopathogenic micromycetes belonging to the genus were notable. Bacterial strains isolated from the vine showed the highest antifungal activity against micromycetes belonging to the genus Penicillium and reduced the radius of phytopathogenic growth to 47–54 mm. Compared with micromycetes belonging to the genus Fusarium, it was also apparent that the pathogen reduced the growth radius to 27–35 mm. Isolation of phytopathogenic micromycetes from the vine allows early detection and prevention of grape diseases. Based on these studies, the identification of antifungal activity of the bacterial strains isolated from the vine and the presence of phytohormones in the culture fluid indicated that it is an essential and environmentally friendly biological tool in the cultivation of grapes for human consumption.

Reducing Water Stress, Germination and Shoot Nutrients Accumulation of Avena sativa L. Following Application of Plant Growth-Promoting Bacteria

ABSTRACT Many ecological factors affect the ability of plants to survive and grow. At the same time, drought causes significant limitations to plant growth in arid regions. This study investigated the effects of bio-fertilizers (Azotobacter vinelandii=F1, Pantoea agglomerans+ Pseudomonas putida=F2, F1+F2, control=C) on reducing the effect of water stress factor 100% (FC=field capacity), 70% (0.7FC), and 40% (0.4FC) on germination, growth, and absorption of some nutrients by Avena sativa L. The results indicated that the germination rate was the highest in F1 + 0.7FC and F1 + 0.4FC, respectively and the lowest germination rate was measured in C + 0.7FC. Treatment F1+F2 + 0.4FC compared to C + 0.4FC significantly reduced the germination rate (p < .01). The highest shoot and root lengths were measured in treatment F1+F2 + 0.4FC, and the lowest shoot and root length was measured in treatment F1+F2+FC. In treatment F2 + 0.7FC, shoot and root dry weight increased significantly (p < .01). Treatment F1 + 0.4FC showed the lowest shoot dry weight. In treatment F1+FC, the highest potassium concentration was measured in treatment F2 + 0.7FC, and the highest iron and zinc were measured. The maximum uptake of iron and zinc was measured in F1+FC and F2 + 0.7FC, respectively. Treatment F1+F2 + 0.4FC showed the lowest uptake of iron, zinc, and manganese. Treatment F1+FC caused to increase in nitrogen, phosphorus, and potassium uptake. Generally, the bio-fertilizers had the highest efficiency under 0.7FC and FC conditions. Fertilizers F1 and F2 separately reduced drought’s impact on plant germination. Fertilizers had no noticeable influence on the uptake of nutrients. Bio-fertilizers applied to A. sativa L. could contribute to the restoration and enhancement of rangelands.

Bacterial diversity associated with the Hatay yellow strain silkworm (Bombyx mori L.): Isolation, identification and characterization

The Hatay yellow strain silkworm (Bombyx mori L.), which is in danger of extinction, is one of the most important local cultural heritages of Türkiye. Bacterial pathogens of silkworm are highly destructive and cause mostly acute diseases. The aim of this study was to determine the bacterial diversity and potential pathogenic bacterial species in infected and dead larvae of Hatay yellow race. A total of 16 bacterial isolates from Hatay yellow race were identified according to their morphological, biochemical and molecular characteristics. The bacterial isolates isolated from infected and dead larvae of Hatay yellow race were Staphylococcus sp. (BM-1), Staphylococcus xylosus (BM-5), Staphylococcus succinus (BM-7), Bacillus thuringiensis (BM-8), Bacillus subtilis (BM-9), Bacillus sp. (BM-10), Staphylococcus saprophyticus (BM-16, BM-19), Klebsiella sp. (BM-17), Staphylococcus arlettae (BM-18), Pseudomonas aeruginosa (BM-20), Enterococcus mundtii (BM-21), Pantoea agglomerans (BM-22), Kluyvera intermedia (BM-23), Serratia sp. (BM-24), Mammaliicoccus sciuri (BM-25). The high bacterial density and number of species indicate that Hatay yellow race is highly susceptible to bacterial diseases. Insecticidal activity studies revealed that species belonging to Bacillus and Staphylococcus genera are important pathogens of hybrid silkworm culture and Hatay yellow race.

Valorization of Chlorella thermophila biomass cultivated in dairy wastewater for biopesticide production against bacterial rice blight: a circular biorefinery approach

Biopesticides offer a sustainable and efficient alternative to synthetic pesticides, providing a safer and more eco-friendly solution to pest management. The present work proposes an innovative approach that integrates crop protection and wastewater treatment using thermophilic microalgal strain Chlorella thermophila (CT) cultivated in nutrient-rich dairy wastewater as a growth medium. The microalgae was cultivated mixotrophically and was able to reduce both organic carbon as well as nutrient load of the dairy wastewater efficiently. The integrated circular biorefinery approach combines biomass cultivation, extraction of biopesticide compounds, and conversion to biocrude. The antimicrobial activity of the biopesticidal extracts against Xanthomonas oryzae and Pantoea agglomerans, the causative agent of bacterial rice blight, is assessed through in vitro studies. The biomass extract obtained is able to inhibit the growth of both the above-mentioned plant pathogens successfully. Mass spectroscopy analysis indicates the presence of Neophytadiene that has previously been reported for the inhibition of several pathogenic bacteria and fungi. Several other value-added products such as linoleic acid and nervonic acids were also been detected in the microalgal biomass which have extremely high nutraceutical and medicinal values. Furthermore, the study investigates the potential for co-production of biocrude from the biorefinery process via hydrothermal liquefaction. Overall, the findings of this present work represent an innovative and sustainable approach that combines wastewater treatment and crop protection using microalgal biomass.

Hatay İlinde Yetiştirilen Farklı Brassica türlerine ait Minör Sebzelerde Fungal ve Bakteriyel Hastalık Etmenlerinin Belirlenmesi

The Brassicaceae family, commonly known as the Cruciferae or mustard family, encompasses plant species of global economic significance, including oilseed crops, vegetables, as well as condiment purposes. Hatay Province is among the significant regions in Turkey where Brassicaceae family vegetables are cultivated. This study aimed to identify the causative agents of diseases affecting minor Brassica vegetables including cabbage (red and white varieties), broccoli, cauliflower, garden cress, rocket, and radish in the districts of Hatay Province where vegetable cultivation took place during the 2020-2021 growing seasons. Isolations from suspicious cabbage, broccoli, cauliflower, and radish plants exhibiting disease symptoms in the surveyed areas revealed the presence of various fungal disease agents, including Rhizoctonia solani, Sclerotinia sclerotiorum, Fusarium solani, Fusarium oxysporum, Fusarium equiseti, Alternaria alternata, Botrytis cinerea, and Stemphylum sp. Furthermore, obligate parasitic oomycete pathogens such as Albugo lepidii, Albugo candida, and Perofascia lepidii were detected with varying prevalence and incidence rates on leaves and stems of water cress, rocket, and radish plants.&#x0D; In addition to fungal pathogens, primary bacterial pathogens, including Xanthomonas campestris pv. campestris, Pectobacterium carotovorum subsp. carotovorum, Pectobacterium parmentieri, Pseudomonas corrugata, and Pseudomonas cichorii, were identified through morphological, biochemical, pathogenicity tests, and MALDI-TOF analyses. Pantoea agglomerans, Pseudomonas marginalis, Pseudomonas fluorescens, Enterobacter cloacae, and Bacillus pumilus were also identified as opportunistic soft rot bacterial pathogens.&#x0D; To the best of our knowledge, this is the first report of F. solani, F. oxysporum, F. equiseti, A. alternata, B. cinerea, Stemphylum sp., P. parmentieri, P. corrugata, and P. cichorii as primary bacterial pathogens, P. agglomerans, P. marginalis, P. fluorescens, E. cloacae, and B. pumilus as opportunistic secondary soft rot bacterial disease agent affecting different minor Brassica vegetables, such as cabbage (red and white varieties), broccoli, cauliflower, radish, rocket, and garden cress, grown in Turkey.

Physiological and transcriptomic analyses of response of walnuts (Juglans regia) to Pantoea agglomerans infection.

Walnut blight is a serious bacterial disease that affects the yield and quality of walnuts. Pantoea agglomerans is one of the main causative agents of walnut blight. However, there have been few studies on the response of walnuts to P. agglomerans infection. In this study, the soluble sugar, photosynthesis, antioxidant enzyme activities, and secondary metabolites were measured, and the transcriptomic analysis was performed to determine the response of walnut tissue cultures to P. agglomerans infection. After pathogen inoculation, the soluble sugar content decreased, and photosynthesis was inhibited. Antioxidant enzyme (superoxide dismutase and peroxidase) activities and secondary metabolites (phenol and flavonoid) contents increased, especially in the early stages of inoculation. Transcriptomic analysis revealed that the phenylpropanoid biosynthesis pathway is induced after infection, and pathogen infection promotes ABA and ethylene signal transduction and inhibits auxin signaling. In addition, SA and JA-related gene expression was altered after inoculation with P. agglomerans, and the FLS- and calcium-mediated disease resistance signaling pathways were activated. Furthermore, our results suggested an involvement of the R-protein RPM-mediated disease resistance pathway in the response of walnuts to bacterial infections. Our findings indicated that phenylpropanoid biosynthesis, hormone signal transduction, and plant-pathogen interaction have key roles in pathogenic inoculation, which provide insights into the molecular mechanisms in the response of walnuts to P. agglomerans infection.

The molecular characterisation of bacteria associated with neonatal necrotising enterocolitis and sepsis which were isolated from hospitals in Bogotá, Colombia

Background: The identification and molecular characterisation of bacteria associated with neonatal necrotising enterocolitis (NNE) and sepsis is very important in clarifying the role such bacteria play in the development of this disease. Methods: The present multicentre study was aimed at characterising bacteria isolated from haemocultures obtained from 20 neonates suffering NNE by using traditional and molecular methodologies (16 S rRNA subunit sequencing and multilocus sequence typing - MLST). Results: NNE incidence in hospitals in Bogotá was also estimated, finding rates similar to and higher than those reported in the literature (1 to 3 cases of NNE per 1,000 live-births). Staphylococcus epidermidis ST2, ST81, and ST126 sequence types were identified by using these two molecular techniques; the Escherichia coli ST394 sequence type was also identified. Species could not be identified for the Pantoea agglomerans isolate due to the high degree of intra-species identity. Interestingly, the bacterial isolates from the two neonates who died were classified in the same sequence type (i.e. S. epidermidis ST81), even though they came from different hospitals. Conclusion: Such molecular techniques allow characterising bacterial pathogen populations occurring in one or more hospitals in a particular city or determined geographical area and support taking more specific preventative measures directed against such particular clones.

Microbial Load of Hand Sanitizer Dispensers—A University Hospital Study

Hospital-acquired infections are a significant concern in healthcare settings, leading to patient safety risks, increased morbidity and mortality, and financial burdens. Hand hygiene is crucial in preventing the spread of bacteria in hospitals and communities. Manual hand sanitizer dispensers can harbor presumptive pathogenic bacteria and act as fomites for bacterial transmission. This study aimed to assess the microbial contamination of manual hand sanitizer dispensers in a hospital setting and to study their antibiotic resistance profiles. Samples were collected using sterile cotton swabs and then inoculated into brain heart infusion broth. Subsequent subcultures were performed on both blood and MacConkey agar. The isolates were then identified using the Bruker MALDI Biotyper (Bruker Daltonik, Bremen, Germany) to the species level. Sampling was conducted in various wards and in the hospital and the University areas on dispenser levers and nozzle areas. The results showed that all samples yielded one or more bacterial species. Bacterial isolates identified belonged to species commonly found on the skin microflora and some Gram-negative enteric bacilli. Higher colonization was observed on the dispenser lever. Among Gram+ microorganisms, most bacterial species were shown to be sensitive to β-lactams, with the exception of Staphylococcus spp., resistant to AMP (Ampicillin) and Penicillin. However, no Methicillin resistant isolates were detected. Gram− microorganisms such as Pseudomonas luteola were shown to be sensitive to all tested antibiotics, while Pantoea agglomerans was shown to be resistant to AMC (amoxicillin–clavulanic acid). Rifampicin tested only against Bacilli showed resistance. Based on the findings, it is recommended to implement systematic cleaning and proper maintenance of manual dispenser areas or to use automated dispensers to reduce hand contact and minimize microbial contamination. Monitoring the presence of microorganisms in hand sanitizing gels and dispensers is an essential infection control strategy.

Chemical Ecology of Rathayibacter toxicus and Associated Bacteria: Profiling Volatile Compounds for Insights into Annual Ryegrass Toxicity Causative Agent

The study involved the isolation of bacteria from the surface of Rathayibacter toxicus infested ryegrass seeds, followed by an analysis of volatile organic compounds (VOCs) to identify biomarkers associated with each bacterial species. Among the four isolated bacteria (a species of Pantoea, two species of Pseudomonas and R. toxicus), three were evaluated for their antibiosis potential against R. toxicus. The main objective of this research was to characterize the volatile compounds produced by R. toxicus and to assess the capability of the other three bacteria to serve as biological control agents. The volatile chemicals were identified by using headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC–MS) in the aforementioned bacterial species. The identified compounds such as 1-nonanol, geraniol, decanoic acid and 2-decanone may serve as biomarkers for R. toxicus. Additionally, obtained information on VOCs may facilitate chemical communication between bacteria and the nematode which is responsible to carry it to the ryegrass plant. During the antibiosis assay, Pantoea agglomerans and Pseudomonas cedrina, among the endophytic/epiphytic bacterial species, produced compounds that significantly inhibited R. toxicus growth in vitro, with capacity values 22.7 ± 2.3 and 20.0 ± 2.0, respectively. In conclusion, this study's findings have significant implications for the management of annual ryegrass toxicity (ARGT), as they highlight the promising potential of P. agglomerans and Ps. cedrina as viable candidates for biological control strategies in ARGT management.

Preliminary Data on Escherichia coli, Yersinia enterocolitica, and Other Bacteria, as Well as Absent African Swine Fever Virus in the Gut Microbiota of Wild Mice and Voles from Bulgaria

Small mammals are bioindicator organisms, and, through their gut microbiota (GM), could be carriers of pathogens and resistant bacteria. Also, wild GM composition has been suggested to have large implications for conservation efforts. Seventeen bacterial species were obtained from intestinal samples of Bulgarian yellow-necked mice (Apodemus flavicollis) and bank voles (Myodes glareolus) via classic microbiological cultivation and biochemical identification. Twelve Gram-negative—Escherichia coli, Yersinia enterocolitica, Yersinia kristensenii, Hafnia alvei, Serratia liquefaciens, Serratia marcescens, Serratia proteamaculans, Pseudescherichia vulneris, Klebsiella pneumoniae ssp. ozaenae, Enterobacter cloacea, Pantoea agglomerans, Pseudomonas fluorescens group—and five Gram-positive bacteria, Enterococcus faecium, Enterococcus faecalis, Enterococcus hirae, Bacillus thuringiensis, and Lysinibacillus sphaericus, were discovered. Enterobacteriaceae was the most abundant family. The isolates belonged to one of the major reported taxa in rodents, Firmicutes (the Gram-positive species) and to the less abundant, but still among the first, phyla, Proteobacteria (the Gram-negative strains). We did not find any members of the other major phylum, Bacteroidetes, likely due to lack of metagenomic techniques. E. coli and Y. enterocolitica were confirmed with polymerase chain reaction. Almost all strains had pathogenic potential, but the good condition of the test animals suggests their commensal role. The Y. enterocolitica strains did not have the ail pathogenicity gene. There was high prevalence of multi-drug resistance (MDR), but for the expected species with high level of intrinsic resistance, such as the enterococci and S. marcescens. E. coli and some other species had very low antimicrobial resistance (AMR), in line with other studies of wild rodents. Many of the strains had biotechnological potential; e.g., B. thuringiensis is the most used biological insecticide, with its proteins incorporated into the Bt genetically modified maize. The GM of the tested wild mice and voles from Bulgaria proved to be a source of bacterial diversity; many of the strains were promising in terms of biotechnology, and, in addition, the samples did not contain the African swine fever virus.

Effects of oral administration of lipopolysaccharide derived from Pantoea agglomerans on innate immunity of mammary glands in dairy goats

This study aimed to evaluate the effect of orally administered lipopolysaccharide (LPS) derived from Pantoea agglomerans (LPSpa) on innate immune functions, including the concentrations of antimicrobial components and interleukin (IL)-10 in goat milk, for the prevention of goat mastitis. Twelve Tokara goats were divided into two groups of six goats. Goats in the LPSpa and control groups were orally administrated with 0.4 g/kg dextrin with or without 0.02 mg/kg LPSpa for 7 days (day 0–6), respectively. After treatment (i.e., day 7), 1 μg LPS from Escherichia coli O111 (LPSec) was infused into one side of the udder in both groups to induce mastitis. Milk from all sides of the udder, saliva, and feces were collected on days 0 and 7. After LPSec infusion into the udders, milk was collected from the infused side of the udder on days 8, 10, and 12. Milk yields and somatic cell counts were recorded during the examination period. The concentrations of immunoglobulin (Ig) A in saliva, feces, and milk and the concentrations of lactoferrin, goat β defensin-1 (GBD1), S100A7, and IL-10 in milk were measured. After LPSpa oral administration, the concentrations of GBD-1 and IL-10 in the milk of the LPSpa group were significantly higher on day 7 than those in the control group, and the concentration of IgA in the feces tended to be higher than that in the control group. After LPSec intramammary infusion, S100A7 concentration on day 12 was significantly lower in the LPSpa group than in the control group. These findings suggest that the oral administration of LPSpa may prevent mastitis by increasing the concentration of GBD1 in milk.

Expression of Ice Nucleation Protein in Bacillus amyloliquefaciens and Its Application in Food Freezing Process.

To produce food-grade ice nucleators, a 3.77 kb ice nucleation gene (iceE) isolated from Pantoea agglomerans (Erwinia herbicola) was introduced into the Gram-positive microorganism Bacillus amyloliquefaciens for the first time. The differential scanning calorimetry (DSC) results indicated that recombined strain B9-INP was an effective ice nucleator for controlling the supercooling point of distilled water at low concentrations. In the presence of B9-INP cells, model food systems, including sucrose solution and sodium chloride solution, different pH solutions froze at a relatively high subzero temperature, thus increasing the supercooling point by 5.8~16.7 °C. Moreover, B9-INP also facilitated model and real food systems to freeze at -6 °C. This recombinant strain not only improved the freezing temperature of food systems but also shortened the total freezing time, thus saving energy and reducing consumption. The results suggest that B9-INP has great application potential in the frozen food industry.

Plant Growth Promoting (PGP) Performances and Diversity of Bacterial Species Isolated from Olive (Olea europaea L.) Rhizosphere in Arid and Semi-arid Regions of Morocco

Plant Growth Promoting Rhizobacteria (PGPR) play an essential role in enhancing plant growth, health and yield. In this study, we describe the isolation of PGPR associated with the olive tree (Olea europaea L.) grown in three Moroccan regions of Zouala, Errachidia, and Essaouira. In these regions, we isolated 95 PGPRs from rhizosphere of Olive trees, 78% of them were characterized by their tolerance to a salinity of 4-11%. We also found that 39% of these PGPRs were phosphate solubilizing bacteria (PSB) with a solubilization ability greater than 100 µg/mL. In fact, Pantoea agglomerans (MRC_ZO_17) and Enterobacter ludwigii (MRC_ZO_97), showed the highest phosphate solubilization rates of ~450 µg/mL and ~196 µg/mL, respectively. In addition to their ability to solubilize phosphate, various isolates had the ability to produce Indole-3-acetic acid (IAA). For instance, E. ludwigii (MRC_ZO_97) had an IAA production of ~60.48 g/mL. In the region of Zouala, characterized by relatively higher salinity and lower rate of organic matter, Firmicutes isolates account for 87% of the isolated rhizobacteria. Interestingly, we found that the olive tree-associated PGPRs vary significantly between the three sampled regions. Several rhizobacteria isolated in this study are excellent candidates for formulation as bioinocula for plants in saline soils.

The complete genome sequence of Pantoea agglomerans NBBC-01, isolated from rot potato tubers.

The Gram-negative bacterium Pantoea agglomerans has been isolated from various habitats including disease plants. Here, we present the genome of P. agglomerans strain NBBC-01 obtained from rotten potatoes that were infected by Ditylenchus desstructor. The genome information will prove advantageous in elucidating its ecological role.

Klebsiella pneumoniae Metallobetalactamase in the neonatology service of the Abel Santamaría Hospital: case report

Introduction: Klebsiella pneumoniae is considered a superbacteria due to its extreme resistance to most antimicrobials and because it produces carbapenemases, enzymes that hydrolyze carbapenem antibiotics. This threat is exacerbated by the reduction in the discovery of new antibiotics. Case presentation: Preterm newborn of 32,3 weeks of gestation and birth weight of 1790 grams, born on January 3, 2023 with mild neonatal depression and early sepsis due to coagulase-negative staphylococcus. It worsens, presenting jaundice, anemia and thrombocytopenia, with blood cultures positive for Enterobacter Gergoviae and later for Enterobacter agglomerans. Antibiotic therapy was based on different antibiograms depending on the germ isolated without presenting clinical improvement. The isolation obtained from Enterobacter aglomerans showed KPC resistance phenotype, so the sample was referred to the “Pedro Kouri” Institute of Tropical Medicine, where the growth of Klebsiella pneumoniae with NDM metallobetalactamase resistance phenotype was obtained, only Sensitive to colistin and Intermediate to phosphokine. Contact precautions and treatment with colistin and phosphokine are applied. As a result, the patient resolves the infection and it is not transmitted to other neonates in the service. Conclusions: Klebsiella pneumoniae NDM infections constitute a danger due to the few therapeutic options, leaving colistin as the only alternative, due to resistance to carbapenems and due to the limitations in its identification in microbiology laboratories at the provincial level. The rational use of antimicrobials and microbiological surveillance are important for its control.