Staphylococcus pseudintermedius is an opportunistic bacterium previously associated with dogs but has recently been found in human infections, raising zoonotic concerns. Genomic characterization of human S. pseudintermedius isolates can provide preliminary information on antibiotic resistance, pathogenicity, and genomic features relevant to host range. Two S. pseudintermedius isolates (hereafter referred to as S. pseudintermedius EGH1 and S. pseudintermedius EGH2) from human clinical samples in Egypt were sequenced using the Illumina NovaSeq X Plus platform. To assess genetic relatedness to human S. pseudintermedius isolates worldwide, multilocus sequence typing (MLST), pangenome analysis, and antimicrobial resistance gene profiling were performed. The sequencing produced a total of 9,499,989 reads for S. pseudintermedius EGH1 and 9,567,531 reads for S. pseudintermedius EGH2. Sequences were assembled with Geneious Prime® 2025 and annotated using NCBI Prokaryotic Genome Annotation Pipeline v6.10. Pangenome analysis identified 9574 genes, comprising 1681 core genes (17.56%), 180 soft-core genes (1.88%), 837 shell genes (8.74%), and 6876 cloud genes (71.82%). MLST was conducted on human S. pseudintermedius genome assemblies using MLST v2.23.0. The analysis revealed both isolates as novel sequence types: S. pseudintermedius EGH1 was assigned ST-3037 with a new allele (purA-107), and S. pseudintermedius EGH2 was assigned ST-2874. Clonal relationships among S. pseudintermedius isolates were evaluated using the eBURST algorithm. This study presents the first next-generation genome sequencing and comparative genomic analysis of S. pseudintermedius isolates from humans in Egypt. Future studies integrating genomic, epidemiological, and phenotypic data are required.

Background: Gamma-aminobutyric acid (GABA) is the principal inhibitory neurotransmitter in the central nervous system and exerts multiple health-promoting effects, including antidepressant, hypotensive, immunomodulatory, and antidiabetic actions. Previous studies have reported a positive correlation between the abundance of Bifidobacterium species in the gut and fecal GABA levels. However, the direct contribution of specific GABA-producing Bifidobacterium strains and the associated interaction with prebiotics remain insufficiently characterized. Methods: This study aimed to elucidate the direct effects of a GABA-producing strain, Bifidobacterium adolescentis 4-2, in combination with the prebiotic mannooligosaccharides (MOS), on fecal GABA concentrations using the Kobe University Human Intestinal Microbiota Model (KUHIMM), an in vitro simulation of the human colonic microbiota. GABA levels were quantified via high-performance liquid chromatography, and changes in microbial composition following oligosaccharide supplementation were assessed by next-generation sequencing of 16S rRNA genes. The presence and activity of the β-mannosidase producing genes, essential for MOS degradation and present in the B. adolescentis 4-2 genome, were evaluated using enzymatic assays. Results: B. adolescentis 4-2 significantly increased fecal GABA levels within the KUHIMM. MOS supplementation elevated GABA levels, reduced fecal culture pH, and increased the relative abundance of Actinobacteria, particularly the Bifidobacterium species. Notably, the combined application of MOS and B. adolescentis 4-2 produced a synergistic increase in GABA production compared with the individual application of each component. β-mannosidase activity assays confirmed the effective utilization of MOS by B. adolescentis 4-2, supporting its role in enhancing GABA biosynthesis. Conclusion: These findings demonstrate a synergistic interaction between MOS and B. adolescentis 4-2 in promoting microbial GABA production in the KUHIMM in vitro. This synbiotic combination shows promise for modulating gut-derived GABA levels in vitro and warrants further investigation in animal models and human clinical studies.

Vibrio cholerae is the causative agent of cholera and remains a significant public health concern in Bangladesh. Contaminated water, undercooking, and lack of personal hygiene during food preparation, handling, transportation, and storage are major causes of cholera transmission through various food sources. Cholera outbreaks linked to food sources pose a major public health issue. The present study aimed to isolate antibiotic-resistant V. cholerae from different food sources. A total of fifty samples, such as raw milk, chicken meat, poa fish, sugarcane juice, and spinach, were collected from different markets in Khulna City, Bangladesh. The overall prevalence of V. cholerae from different food sources was 38 %, with 19 isolates of V. cholerae successfully identified. The highest count of V. cholerae was recorded at 5.93 +/- 0.15 log CFU/mL in poa fish, while the lowest count was 2.43 +/- 0.31 log CFU/mL in sugarcane juice. The isolated V. cholerae was subjected to antibiotic susceptibility testing using ampicillin, ciprofloxacin, azithromycin, gentamicin, tetracycline, and norfloxacin. The result showed that the highest antibiotic resistance was 73 % and 69 % to ampicillin and tetracycline, respectively. In contrast, the highest antibiotic sensitivity against V. cholerae was 43 % and 45 % for ciprofloxacin and azithromycin, respectively. The level of antibiotic-resistant V. cholerae represents a significant public health concern in Khulna City, Bangladesh, underscoring the urgent need for coordinated efforts to mitigate its impact.

Staphylococcus pseudintermedius is an opportunistic pathogen that is largely associated with canine hosts but is becoming more widely recognized as a zoonotic pathogen. Understanding its genetic and phenotypic properties, such as virulence factors and antimicrobial resistance (AMR) profiles, is critical for infection control and vaccine development. In this study, we isolated and molecularly characterized three S. pseudintermedius isolates from dogs (hereafter referred to as S. pseudintermedius D8) and humans (hereafter referred to as S. pseudintermedius H10 and S. pseudintermedius H11) in Egypt. All three isolates showed 100% sequence identity with the nuc gene of the S. pseudintermedius SP_11304-3A reference genome. Multilocus sequence typing (MLST) revealed novel sequence types (STs) in the three isolates. The AMR determinants varied substantially among the isolates. While the mecA gene was absent, blaZ was detected in the canine isolate, indicating beta-lactamase-mediated penicillin resistance. Additionally, tetK and tetM genes were found conferring tetracycline resistance in different isolates. Resistance genes for aminoglycosides, chloramphenicol, fusidic acid, macrolides, streptothricin, and trimethoprim were also identified. All isolates were positive for key virulence genes, including immune evasion (AdsA), coagulase (coa), immunoglobulin-binding protein (sbi/spsK), exfoliative toxin (speta), enterotoxins (se-int and siet), fibrinogen binding protein gene (fnbB), and two-component pore-forming leukocidin genes (lukF and lukS). The S. pseudintermedius H11 isolate uniquely harbored the neuraminidase gene (nanB), while none of the isolates contained the gene coding for immunoglobulin G binding protein (spsQ). These findings highlight the differences in virulence and antimicrobial resistance genes among these S. pseudintermedius isolates, underlining the need for global surveillance and molecular characterization of this pathogen.

Abstract Background Bifidobacteria are gram-positive, probiotic, and generally regarded as safe bacteria. Techniques such as transformation, gene knockout, and heterologous gene expression have been established for Bifidobacterium, indicating that this bacterium can be used as a cell factory platform. However, there are limited previous reports in this field, likely because of factors such as the highly anaerobic nature of this bacterium. Bifidobacterium adolescentis is among the most oxygen-sensitive Bifidobacterium species. It shows strain-specific gamma-aminobutyric acid (GABA) production. GABA is a potent bioactive compound with numerous physiological and psychological functions. In this study, we investigated whether B. adolesentis could be used for mass production of GABA. Results The B. adolescentis 4–2 strain isolated from a healthy adult human produced approximately 14 mM GABA. It carried gadB and gadC, which encode glutamate decarboxylase and glutamate GABA antiporter, respectively. We constructed pKKT427::Pori-gadBC and pKKT427::Pgap-gadBC plasmids carrying gadBC driven by the original gadB (ori) and gap promoters, respectively. Recombinants of Bifidobacterium were then constructed. Two recombinants with high production abilities, monitored by two different promoters, were investigated. GABA production was improved by adjusting the fermentation parameters, including the substrate concentration, initial culture pH, and co-factor supplementation, using response surface methodology. The optimum initial cultivation pH varied when the promoter region was changed. The ori promoter was induced under acidic conditions (pH 5.2:4.4), whereas the constitutive gap promoter showed enhanced GABA production at pH 6.0. Fed-batch fermentation was used to validate the optimum fermentation parameters, in which approximately 415 mM GABA was produced. The conversion ratio of glutamate to GABA was 92–100%. Conclusion We report high GABA production in recombinant B. adolescentis. This study provides a foundation for using Bifidobacterium as a cell factory platform for industrial production of GABA.

Methicillin-resistant Staphylococcus aureus (MRSA) has a major public health concern. It can be identified throughout the chain of production for poultry, which raises questions regarding potential transmission from farm to consumer. MRSA has zoonotic significance and can be transmitted to humans and poultry. Several studies have been carried out on MRSA on poultry, but this study was conducted to find out the whole scenario of MRSA at the farm level. A total of 100 samples were collected randomly from different poultry farms and retail shops in Khulna city to investigate this study. MRSA was isolated and identified by culturing antibiotic susceptibility testing, and polymerase chain reaction (PCR). Among the 100 samples, 57% were positive for S. aureusand 80.70% of the isolated S. aureus showed hemolysis on blood agar. Among the 57 isolates, 78.94% were MRSA (oxacillin) and 19.29% were vancomycin-resistant Staphylococcus aureus (VRSA) phenotypically. Surprisingly, 59.64% of S. aureus results showed a positive mecA gene. It is also concerning that 60% of broiler meat and 53.84% of farm personnel were infected with MRSA. The present study revealed that MRSA could be transmitted from poultry to humans.

Bifidobacterium adolescentis 4-2 was isolated from healthy human feces. Here, we report a draft genome sequence of this bacterium, which may clarify the functionality of gut microbiota-brain communication. The draft genome comprises 2.39 Mb, with an average G+C content of 59.2% and 2,028 coding DNA sequences. An operon for gamma aminobutyric acid (GABA) biosynthesis was observed in the draft genome.

A series of Bifidobacterium-Escherichia coli shuttle vectors (pKO403-lacZ'-Cm, pKO403-lacZ'-Sp, pKO403-lacZ'-p15A) were constructed based on the pKO403 backbone, which carries a temperature-sensitive replication origin. These vectors carry the lacZ'α fragment, overhung by two facing type IIS restriction sites, for blue-white selection and seamless gene cloning. These vectors are useful for gene knockout or multigene integration into the chromosome of Bifidobacterium.

Recent studies have shown that the gut microbiota modulates the physical and psychological functions of the host through several modes of action. One of them is mediating the production of active neurotransmitters, such as serotonin and gamma-aminobutyric acid (GABA). GABA is the major inhibitory neurotransmitter in the central nervous system. Here, we analyzed the relationship between fecal GABA concentration and microbial composition in more than 70 human participants. The gut microbiome composition was analyzed using next-generation sequencing based on 16S ribosomal RNA. High-performance liquid chromatography was used to evaluate the neurotransmitters GABA and glutamate. The GABA level was detected in a broad range (0–330 µg/g feces). The participants’ samples were classified into high (>100 µg/g), medium (10–100 µg/g), and low (<10 µg/g) groups, based on fecal GABA concentration. The results reveal that the microbiome of the high-GABA samples had lower alpha diversity than the other samples. Beta diversity analysis showed significant (p < 0.05) separation between the high-GABA samples and others. Furthermore, we surveyed the abundance of specific GABA producer biomarkers among the microbiomes of tested samples. The family Bifidobacteriaceae exhibited high abundance in the microbiome of the high-GABA group. This study demonstrated that Bifidobacterium abundance was associated with high fecal GABA content in healthy human subjects. These results may aid the development of potential probiotics to improve microbial GABA production, which can support the maintenance of the physical and psychiatric health of the host.

Mounting evidence elucidates the impact of gut microbiota on the maintenance of host’s physical and psychological conditions. The gut microbiota can produce its effects through neural, endocrine, and immune pathways. Specific gut members, such as lactobacilli and bifidobacteria, have shown unique abilities to affect the host’s mental health, and hence, they are called psychobiotics. Several studies, on both rodents and humans, have confirmed the role of Bifidobacterium in the regulation of anxiety, mood, cognition, and pain. Here, we summarize the currently available evidence that suggests the roles of bifidobacteria in gut microbiota–brain communication and highlight the prospects of this research field. The action of Bifidobacterium has been found to be strain specific. We discuss here the currently reported mechanisms of action of different Bifidobacterium strains. However, more strategic investigations are needed to fully understand the detailed mechanisms of action of Bifidobacterium as psychobiotic bacteria.

Based on the production method for "funa-narezushi," which has a long fermentation period, we established technology to manufacture "ayu-narezushi" made from ayu (Plecoglossus altivelis altivelis). The pH of raw ayu is 6.15. After 10 months of fermentation, the pH in the muscle portion of narezushi drops to between 4.20 and 4.70, and to between 4.00 and 4.65 in nare-meshi. The predominant microorganisms in ayu-narezushi were Lactobacillus sp. (2.57 +/- 0.2 x 10(4) - 1.13 +/- 0.46 x 10(9) cfu/g), mold or yeast (2.95 +/- 0.07 x 10(4) - 2.0 +/- 0.0 x 10(8) cfu/g), and Bacillus sp. (2.83 +/- 0.74 x 10(3)-2.26 +/- 0.23 x 10(4) cfu/g). Based on microflora analysis using a next-generation sequencer, the predominant bacteria in fermented ayu-hon-narezushi belonged to the genera Lactobacillus, Tetragenococcus and Staphylococcus. After 10 months of fermentation, the free amino acid content in nare-ayu-zushi increased seven-fold from that in raw ayu, and 10- to 15-fold in nare-meshi from that in meshi. In particular, the glutamic acid and hydrophobic amino acid content increased in both the fish and the rice. We isolated Lactobacillus buchneri, L. parabuchneri and L. plantarum which produce gamma-aminobutyric acid (GABA) from glutamic acid during fermentation. It is thought that these microorganisms also produce GABA in nare-zushi.

Canine distemper and parvovirus infections are amongst of the most important infectious diseases of dogs. yntneceR, the range of reports of vaccinated dogs that developed canine distemper and parvovirus infections have multiplied throughout the world. The goals of this study were to evaluate the immune and hematological responses against canine distemper virus (CDV) and canine parvovirus (CPV) after vaccination using two commercially available vaccines. In addition, the antigenic differences between the vaccine strains of CDV and CPV and the current wild-type strains were analyzed to determine possible relationships between these vaccine strains and recent field outbreaks in vaccinated populations. The immune response of both vaccines was determined using serum neutralization and Dot-ELISA. Specific neutralizing antibodies against canine distemper and parvovirus were present in the sera of dogs three weeks after the initial vaccination for both vaccines. Peak antibody titers were documented from the second month post vaccination. Both vaccines were demonstrated to be safe and stimulate a humoral immune response. Results of serum neutralization test and Dot-ELISA were closely similar and correlated with each other. Genetic variations between strains included in both commercial vaccines and circulating wild-type strains suggest that variant strains are most likely responsible for field outbreaks of CDV and CPV in vaccinated dogs.

A series of new Escherichia coli entry vectors (pIIS18-SapI, pIIS18-BsmBI, pIIS18-BsaI, pIIS18-BfuAI-1, and pIIS18-BfuAI-2) was constructed based on a modified pUC18 backbone, which carried newly designed multiple cloning sites, consisting of two facing type IIS enzyme cleavage sites and one blunt-end enzyme cleavage site. These vectors are useful for seamless gene cloning.