Unraveling the metabolic network of volatile flavor dynamics development during the golden pomfret fermentation driven by core bacteria: a combined multi-omics analysis.

Background: Plant growth promoting bacteria (PGPB) are non-pathogenic bacteria that enhance plant growth through several mechanisms such as nutrient mobilization, phytohormones production, defense against phytopathogens, and alleviation of plant stress. Hence, these bacteria are used as ecologic biofertilizers to diminish the use of agrochemicals. Nevertheless, some PGPR strains can harbor antibiotic resistance determinants and the possibility of spreading them upon releasing these bacteria is an environmental concern. Objectives: The objectives of this work are as follows: (1) evaluating the antibiotic resistance in a collection of PGPB, and (2) prospecting antibiotic resistance genes in the genomes of PGPB in order to predict the risk for antibiotic resistance dissemination. Methods: The resistance towards 12 antibiotics in a collection of 20 PGPB (10 Gram-positive and 10 Gram-negative strains) has been evaluated using disk diffusion in agar, broth microdilution, and agar dilution tests. In addition, the whole genomes of six strains have been sequenced in order to find the correlation between the resistance levels and AMR genes by using bioinformatic tools. Results: The results indicated a wide range of halo diameters, but in general Gram-negatives showed higher resistance compared to Gram-positives. The four most resistant strains and the two more susceptible strains were selected for further analysis and sequencing the whole genomes. The resistant strains were identified as Achromobacter spanius N6, Leclercia adecarboxylata H17, Priestia aryabhattai strain MHA1, and Bacillus cereus N25. The susceptible strains were identified as Pantoea sp. S3 and Priestia megaterium MS4. Mining antibiotic resistance genes in the genomes confirmed the existence of resistance determinants responsible for the phenotypic behavior, indicating the potential of genomics for predicting antibiotic resistance in PGPB. However, there was not an exact correspondence between the presence of the genes and the level of resistance, suggesting the existence of additional regulatory mechanisms. Conclusions: The information obtained by genomics must be complemented experimentally by tests for antibiotic resistance determination. In this regard, it is necessary to develop a global antibiotic resistance database for PGPB, due to the difficulty of interpretation of the antibiotic susceptibility tests after comparing the experimental results with those tabulated for clinical species.

Background: Mobile phones used in hospital environments can act as vectors for the transmission of microorganisms and contribute to the increase in healthcare-associated infections (HAIs). This study aimed to analyze bacterial contamination on mobile phones used by healthcare professionals in a teaching hospital in Minas Gerais, Brazil. Methods: Samples were collected using swabs from mobile phones. Bacteria were isolated and identified by mass spectrometry (MALDI-TOF MS), and antimicrobial susceptibility profiles were determined using standardized methods. Demographic data were obtained through a structured questionnaire. Results: Forty professionals participated in the study. Coagulase-negative Staphylococcus (CoNS) was identified in 100% of the samples. Twenty-one strains of potentially pathogenic bacteria were isolated, including Klebsiella pneumoniae, Klebsiella oxytoca, Raoultella ornithinolytica, Leclercia adecarboxylata, and Pseudomonas aeruginosa (4.8% each); Staphylococcus aureus, Pantoea septica, Pseudomonas putida, and Ochrobactrum anthropi (9.5% each); and Escherichia coli and Stenotrophomonas maltophilia (19% each). S. aureus isolates were resistant to ampicillin and penicillin, while Enterobacterales species exhibited only intrinsic resistance. The presence of potentially pathogenic bacteria was observed on 41.9% of female participants’ phones and 66.7% of male participants’ phones. Only 27.5% of participants reported routinely disinfecting their mobile devices. Conclusion: Mobile phone hygiene is essential to prevent HAIs. These devices can harbor various bacterial species, representing a potential source of cross-contamination. Adherence to hand hygiene and regular disinfection of mobile phones are fundamental measures to reduce the spread of pathogens in hospital environments.

The increasing frequency of antibiotic resistant bacteria and their dissemination in environmental microbiomes is a critical health concern. Water quality assessment and AMR surveillance are broadly focused on commonly found Enterobacterales, and mainly on the faecal indicator E. coli. In this study, we analysed antibiotic resistance and biofilm formation in 14 environmental isolates belonging to six neglected species. Genetic diversity was assessed by ERIC-PCR. Identified as Cronobacter sakazakii (1), Kluyvera intermedia (1), Leclercia adecarboxylata (1), Raoultella ornithinolytica (8), Raoultella terrigena (1), and Yersinia massiliensis (2), each isolate had a unique and distinct AMR profile. The isolates demonstrated intrinsic resistance to erythromycin and increased resistance to ampicillin and tetracycline. None of the isolates exhibited carbapenem resistance. Ten isolates were MDR. Thirteen out of the 24 investigated ARGs were detected in bacterial genomes. Except for carbapenemases, various β-lactamases (blaTEM, blaCTX-M), and also tet, sul, erm, mef and qnr genes were found. A strong positive correlation was observed between the phenotypic and genotypic resistance. Due to its discriminatory power at the taxonomic level, ERIC-PCR fingerprinting provided a reliable and accurate molecular typing. Negative correlations between the number of ERIC bands, the magnitude of resistance and the biofilm score indicate that strains with abundant ERIC sequences are less likely to be resistant and to adhere to surfaces. This suggests that a high genome plasticity and adaptability prevents specific survival strategies and deserves further attention.

Contamination of hospital surfaces by third-generation cephalosporin-resistant gram-negative bacteria in district hospitals in Mwanza, Tanzania: Urgent need for enhanced infection prevention and control

Regarding the trout microbiota, most information is focused on lactic acid bacteria, which can show beneficial properties. However, in trout farming, mostly pathogenic Gram-positive species were reported, such as Staphylococcus aureus, Listeria monocytogenes, and/or Clostridium spp. In this study, free-living trout were analyzed for Gram-negative microbiota that can cause loss as disease-stimulating agents. Bacteriocin postbiotics should be one of the approaches used to eliminate these agents. In total, 21 strains of different species isolated from the intestinal tract of 50 trout in Slovakia (Salmo trutta and Salmo gairdnerii) were taxonomically allotted into 13 species and 9 genera. This method showed variability in microbiota identified using MALDI-TOF mass spectrometry with the following species: Acinetobacter calcoaceticus, Citrobacter gillenii, Citrobacter freundii, Escherichia coli, Hafnia alvei, Kluyvera cryocrescens, K. intermedia, Leclercia adecarboxylata, Raoultella ornithinolytica, Pseudomonas fragi, Ps. putida, Ps. lundensis, Ps. teatrolens, and Serratia fonticola. Most strains were susceptible to the antibiotics used, reaching inhibitory zones up to 29 mm. On the other hand, 3 out of 21 strains (14%) were susceptible to nine enterocins- postbiotics (Hafnia alvei Hal281, Pseudomonas putida Pp391, and Ps. fragi Pf 284), with inhibitory activity in the range of 100–6400 AU/mL.

Plant growth promoting rhizobacteria (PGPR) involves the utilization of large array of soil bacteria to improve yield and plant growth. The bio-fertilizer with plant growth promoting rhizobacteria (PGPR) is reported to influence the growth, yield, quality and nutrient uptake by a variety of mechanisms. PGPR are reported to synthesize phyto-hormones such as indole-3-acetic acid (IAA), volatile organic compounds, increased mineral nutrient solubilization, nitrogen fixation, making nutrients available for the plant, repression of soil borne pathogens by the production of hydrogen cyanide and siderophore. India is an agriculture dominated country having largest livestock population in the world. Apart from this, livestock rearing is one of the major occupations in India that provides manure, forms important source of food and cash income to million. This domestication requires fodder which comes from local land areas, nurseries or habitat around the domestication. Providing a good fodder value, quality is necessary for livelihood. One such tree is Grewia optiva which is a multipurpose tree from tiliaceae family widely used as fodder in Norther Himalayan regions. Various studies have documented the increased health and productivity of different plant species by the application of plant growth promoting rhizobacteria under both normal and stressed conditions. The plant-beneficial rhizobacteria may decrease the global dependence on hazardous agricultural chemicals which destabilize the agro-ecosystem. The present investigation was conducted with aim of isolating and identifying the bacterial isolates from rhizopheric soil of Grewia optiva on the basis of different agroclimatic zone of Himachal Pradesh and evaluate them for PGPR traits to increase fodder quality. A total of 99 bacterial isolates were isolated and screened out of which 23 isolates were positive for PGPR traits. The isolates which showed maximum activity were further tested for quantitative estimation of growth promoting traits. Among the 23 isolates two isolates HKD1 and HSD8 demonstrated best results. HKD1 showed maximum P- solubilization (74.40 µg/ml), siderophore (71.50 µg/ml) and IAA (68.76 µg/ml) whereas HSD8 showed maximum P-solubilization (70.60 µg/ml), siderophore (66.56 µg/ml) and IAA (65.76 µg/ml). These isolates were further identified on the basis of 16S rDNA gene sequence. The two isolates were identified as Leclercia adecarboxylata and Enterobacter ludwigii. These isolates were further screened for biocontrol activity against Fusarium oxysporum and Rhizoctonia solani and were able to inhibit their growth. On the basis of plant growth promoting traits, two isolates HKD1 and HSD8 were selected and applied as biofertilizers for growth promotion of G. optiva. The biofertilizer with 40% RDF significantly increased the shoot and root parameters as well as fodder parameters. The available NPK content of the soil was also improved with application of biofertilizer.

Bisphenol A degradation by leclercia adecarboxylata and synergistic effects bacterial consortia

Background: Tomato production in Iraq is subject to significant decline due to contamination of agricultural field soils with soil-borne pathogenic fungi, particularly Rhizoctonia solani. Rhizobacteria are the best alternative to chemical fungicides in controlling the disease. Methods: Dual culture approach was employed to assess the antifungal activity of 324 rhizobacterial isolates against R. solani in vitro. Superior antigenic isolates were identified using 16S rRNA, gyrA, gyrB and rpoB gene sequencing. Physiological characteristics such as hydrogen cyanide, protease, chitinase, siderophore and nitrogen fixation of the antigenic isolates were screened. Result: A total of 324 rhizobacterial isolates were extracted from rhizosphere samples, with four isolates demonstrating strong antifungal activity above 66% against R. solani. The isolates were identified as Leclercia adecarboxylata DKS3, Bacillus halotolerans DMC8, Bacillus subtilis NAS1 and Paenibacillus polymyxa TRS4. These isolates demonstrated notable biocontrol and plant growth-promoting traits in vitro, including nitrogen fixation and the generation of protease, chitinase, hydrogen cyanide and siderophores, as well as the solubilization of potassium and phosphate. These attributes are essential for enhancing plant growth and resilience to pathogenic stress. This research highlights the ability of these rhizobacteria to function as effective biocontrol agents and promoters of plant growth in sustainable agriculture.

Integrated role of biochar and PGPR (Leclercia adecarboxylata HW04) in enhancing cadmium phytoremediation and stress tolerance in Glycine max L.

Background: Rhizobacteria are essential for plant health by offering natural antagonism to soil-borne fungi. Rhizobacteria are regarded as an alternative to chemical agents for the integrated control of plant diseases and for enhancing yield in an ecologically sustainable way. Nonetheless, there is a limited comprehension of the precise processes via which rhizobacteria suppress these diseases and the variety of rhizobacterial species implicated. Methods: Through experiments conducted in 2022-2024,the efficiency of 12 rhizobacterial isolates of Alloiococcus otitis BRE6, Aneurinibacillus thermoaerophilus SDV1, Aeribacillus pallidus ECC4, A. thermoaerophilus ECL1, Bacillus megaterium SKE2, Staphylococcus lentus BZD2, Enterobacter cloacae complex BZD3, B. megaterium TNK1, Leclercia adecarboxylata DKS3, B. halotolerans DMC8, B. subtilis NAS1 and Paenibacillus polymyxa TRS4, in controlling soilborne pathogenic fungi of Rhizoctonia solani, Macrophomina phaseolina and Pythium aphanidermatum, the causal agents of tomato root rot disease was evaluated under greenhouse conditions and plant growth parameters were evaluated. Result: The results indicated that the combination treatment of 12 rhizobacterial isolates (COR12) achieved the highest germination rate of tomato seeds in the presence of pathogenic fungi, reaching 100% and the lowest rate of disease incidence and severity, reached 5% and 1%, respectively, compared to the positive control treatment, which reached 82% and 53%, respectively. Representing control disease value of 98% compared to the single bacteria treatments. The COR12 treatment achieved a significant increase in the growth parameters represented by plant height and fresh and dry weight of the shoot and root system in the presence of pathogenic fungi compared to the individual bacterial treatments.

Leclercia adecarboxylata is a gram‐negative, rod‐shaped bacterium commonly found in nature. Its pathogenicity is mild and often results in asymptomatic carriage. However, it can cause sepsis and other life‐threatening illnesses in immunocompromised individuals. Based on previous literature, the common practice of applying many unsafe substances, such as shea butter, to the umbilical cord of newborns for healing remains a significant risk factor for omphalitis and neonatal sepsis in developing countries. This case report describes a neonate showing signs of omphalitis and bacteremia, following the use of shea butter on the umbilical cord. A 10‐day‐old male neonate presented with irritability, refusal to breastfeed, and an erythematous, tender umbilical stump. The blood culture result yielded a gram‐negative rod, Leclercia adecarboxylata, sensitive to cephalosporin, chloramphenicol, and gentamicin. The newborn was treated with empirical first‐line antibiotics according to national guidelines: intravenous (IV) ampicillin and gentamicin for 6 days. The child fully recovered. Therefore, we emphasize the ongoing need for community‐level awareness of proper umbilical cord care at the grassroots in developing countries. Additionally, early bacterial detection and antimicrobial management based on local antibiogram data are vital for successful patient outcomes.

This study aims to explore the pathogenic potential of Leclercia adecarboxylata as a rare pathogen in immunocompetent individuals and to analyze how mental health status may influence susceptibility to infection. We report a case of bacteremia in a 31-year-old immunocompetent female who developed L. adecarboxylata infection during an episode of severe depression. Although the patient exhibited self-harm tendencies, a thorough physical examination did not reveal any external wounds or signs of injury. This case demonstrates that, despite the absence of obvious external infection sources, invasive procedures, or visible trauma, L. adecarboxylata can induce severe bacteremia in immunocompetent individuals. The patient presented with high fever and systemic inflammatory response, with blood cultures confirming the presence of L. adecarboxylata, and chest imaging showing bilateral lower lobe inflammation. Following treatment with ceftriaxone, the patient’s symptoms rapidly improved, and infection markers normalized. This study elucidates the potential mechanisms by which L. adecarboxylata can cause infection in immunocompetent individuals and examines the influence of mental health on infection susceptibility. It provides new insights into the complex relationship between mental illness and infection, highlighting the need for further investigation into how mental health may affect infection risk and its clinical management. In conjunction with existing research, this study discusses how psychological stress and behavioral patterns may increase infection risk and recommends future research to further explore the interplay between mental disorders and infectious diseases.

Maize (Zea mays L.), a key staple crop in Sub-Saharan Africa, is particularly vulnerable to concurrent drought and heat stress, which threatens crop yield and food security. Plant growth-promoting rhizobacteria (PGPR) have shown potential as biofertilizers to enhance plant resilience under such abiotic stresses. This study aimed to (1) identify PGPR isolates tolerant to drought and heat, (2) assess their capacity to mitigate the effects of these stresses on early maize growth, and (3) analyze maize gene expression changes associated with PGPR-induced tolerance. Rhizobacteria were isolated and screened for drought and heat tolerance, alongside key plant growth-promoting (PGP) traits, including phosphorus solubilization, nitrogen fixation, and indole acetic acid production. In vitro and pot trials evaluated the effects of selected isolates on maize growth under stress, using indicators such as shoot length, root and shoot biomass (wet and dry), and leaf water content. Quantitative reverse transcription PCR (qRT-PCR) was employed to profile maize stress response genes. The identified PGPR isolates included Bacillus cereus (11MN1), Bacillus pseudomycoides (21MN1B), Lelliottia amnigena (33MP1), and Leclercia adecarboxylata (36MP8). Greenhouse trials demonstrated that L. amnigena 33MP1, L. adecarboxylata 36MP8, and a mixed culture of isolates (11MN1, 21MN1B, 33MP1, 36MP8) effectively alleviated the adverse effects of concurrent drought and heat stress in maize. Notably, qRT-PCR analysis indicated that PGPR-induced tolerance may involve the modulation of stress response genes CAT2 (catalase 2) and DHN2 (dehydrin 2), which play roles in oxidative stress management and cellular protection. The PGPR isolates identified in this study represent promising bioinoculants for enhancing maize resilience under climate-induced stresses, offering a sustainable approach to improve maize productivity, conserve water, and reduce irrigation needs in drought-prone regions.

Along with affecting oral health, oral microbial communities may also be endogenously translocated to the gut, thereby mediating the development of a range of malignancies in that habitat. While species-level studies have proven the capability of oral pathogens to migrate to the intestine, genetic evidence supporting this mechanism remains insufficient. In this study, we identified over 55,000 oral translocation genes (OTGs) associated with colorectal cancer (CRC) and inflammatory bowel disease (IBD). These genes are primarily involved in signal transduction and cell wall biosynthesis and show consistency in their functions between IBD and CRC. Furthermore, we found that Leclercia adecarboxylata, a newly discovered opportunistic pathogen, has a significantly high abundance in the gut microbiota of colorectal cancer patients. OTGs of this pathogen were enriched in 15 metabolic pathways, including those associated with amino acid and cofactor metabolism. These findings, for the first time, provide evidence at the genetic level of the transfer of oral pathogens to the intestine and offer new insights into the understanding of the roles of oral pathogens in the development of gastrointestinal cancers.

Malaria, a vector-borne disease, is caused by Plasmodium species and transmitted by Anopheles species. Among these vectors, Anopheles subpictus has emerged as a potent malarial vector in coastal areas of India. Numerous studies have highlighted that bacterial communities within mosquito influence vector competence. The present study was designed to isolate and characterize bacterial microbiota from An. subpictus larvae. Isolation and purification of the predominant bacterial strain (ALl) was carried out. Morphological, biochemical, antibiotic susceptibility and molecular characterization of the isolated bacteria was performed. Bacterial isolate (AL1) was found to be rod, gram negative, catalase positive and oxidase negative. AL1 was identified as Leclercia adecarboxylata (Accession number: OR649235) through 16S rRNA ribotyping. Further, the leaf extract of Nyctanthes arbortristis showed inhibitory effect against ALl. The study provided the first report on the isolation of symbiotic bacteria (L. adecarboxylata) from An. subpictus and its control by leaf extract of Nyctanthes arbortristis. Isolated gram-negative bacterial strain might inhibit the development of mosquito vectors and can be implemented for various biological control strategies to combat malaria transmission.

Leclercia adecarboxylata is a gram-negative bacillus that rarely causes infections in children, especially in Thailand. We report a case of a boy with a wound infection and cellulitis after a punctate injury caused by L. adecarboxylata. A previously healthy 12-year-old boy presented with a 2-month history of infected wound and cellulitis on his left sole after a punctate injury in the garden. He experienced recurrent swelling and purulent discharge despite an incision and drainage and a full course of appropriate antibiotics. Plain films of his left foot showed no radiopaque foreign body or evidence of osteomyelitis. L. adecarboxylata was isolated from the wound tissue culture. Incision and drainage followed by a 2-week course of oral amoxicillin/clavulanic acid was prescribed which resulted in a complete resolution of the lesion. This case emphasizes the significance of identifying L. adecarboxylata as a possible cause of soft tissue infections in Thai children, especially those with a history of puncture wounds. Unusual pathogens should be considered when standard treatments fail to eliminate the infection.

Mercury-tolerant metalophiles: A bio tool for remediation of mercury (Hg) affected Environs

Background: A gastric ulcer (GU) is a damage to the gaster's mucous layer that penetrates the muscular mucosa and is more than 5 mm in diameter. The study in Indonesia revealed that GU about 37.4% of the bleeding incidence in patients aged >60 years undergoing upper gastrointestinal tract endoscopy. The sequencing technology has strengthened the hypothesis that gastroduodenal diseases such as GU are not just the result of H. pylori infection, but that dysbiosis has a role to play. Methods : This study was conducted involving a suspected GU in 72 patients, who underwent endoscopy from December 2023 to March 2024. 56 people met the research inclusion criteria used in this study. The participants signed an informed consent form. We analyzed the types of microbiota by extracting DNA samples from gastric tissue biopsies using the 16S rRNA gene sequencing method to identify the most dominant microbiota. Result : The distribution of microbiota in gastric ulcers revealed that the most prevalent species were E. coli and S. maltophilia, each at 17.9%, followed by Acinetobacter sp and Prevotella sp at 12.5% each. E. cloacae accounted for 10.7%, K. pneumoniae for 8.9%, and Bacteroidetes sp for 3.6%. The species Agrobacterium tumefaciens, Atlantibacter subterranea, Burkholderia sp, Citrobacter freundii, Leclercia adecarboxylata strain, Rahnella sp, Salmonella enterica, Segatella oris, and Streptomyces sp each represented 1.8%. Conclusion: In gastric ulcers, the dominant microbiota are E. coli, S. maltophilia, Acinetobacter sp., Prevotella sp., E. cloacae, K. pneumoniae, and Bacteroidetes sp.

During 2018–2021, eight septic transfusion reactions occurred from transfusion of platelet units contaminated with Acinetobacter spp., Staphylococcus saprophyticus, Leclercia adecarboxylata, or a combination of those environmental organisms. Whether biofilm formation contributed to evasion of bacterial risk mitigations, including bacterial culture, point-of-care testing, or pathogen-reduction technology, is unclear. We designed a 12-well plate-based method to evaluate environmental determinants of single-species and multispecies biofilm formation in platelets. We evaluated bacteria isolated from septic transfusion reactions for biofilm formation by using crystal violet staining and enumeration of adherent bacteria. Most combinations of bacteria had enhanced biofilm production compared with single bacteria. Combinations involving L. adecarboxylata had increased crystal violet biofilm production and adherent bacteria. This study demonstrates that transfusion-relevant bacteria can produce biofilms well together. More work is needed to clarify the effect of biofilms on platelet bacterial risk control strategies, but US Food and Drug Administration–recommended strategies remain acceptable.