Introduction Lactiplantibacillus plantarum is one of the most varied species of lactic acid bacteria in various environments. Probiotics are beneficial organisms that help balance the gut microbiome and promote general health. The purpose of this study was to perform preliminary phenotypic and genetic characterization of the probiotic strain L. plantarum 022AE. Method Using hybrid assembly, L. plantarum 022AE was sequenced, producing a 3.23 Mb scaffold. Using NCBI-BLASTN, the strain's identification was verified. Genome annotation was used to evaluate safety characteristics. In vitro tests were employed to assess cytotoxicity, antibacterial activity, bile acid tolerance, epithelial adhesion, surface characteristics, cell lining to verify in vivo adhesion, and antibiotic susceptibility (CLSI). Genes associated with virulence, adhesion, and stress survival were discovered by comparative genomics. The safety and probiotic qualities of L. plantarum 022AE were shown to be favourable by full-genome analysis and phenotypic assessment. Results For complete genome sequencing of L. plantarum 022AE, a single scaffold of 3,234,271 bp was obtained via hybrid assembly. NCBI-BLASTN tools analysis showed L. plantarum 022AE to be 100% identical to the reference strain HAC01. Gene annotation and downstream analysis revealed safety attributes, like absence of transferable antibiotic resistance genes, virulence factor genes, active biogenic amine-producing genes, enterotoxin genes, emetic toxin genes, and prophage sequences. In vitro phenotypic characterization showed that the strain was bile- and acid-tolerant, attached to intestinal epithelial cells, and exhibited favorable cell surface properties and antimicrobial activity against key pathogens. It was susceptible to CLSI-recommended antibiotics and produced no cytotoxicity or enterotoxicity. Comparative genome analysis of L. plantarum 022AE revealed genetic determinants for survival in stress environments, cell adhesion, and virulence factor genes. Discussion Genomic analysis was instrumental in concluding the safety of L. plantarum 022AE. Integrated genetic and phenotypic analysis contributed in establishing the stability (in-vitro gut model, acid and bile), GI persistence (adherence to Caco2 and mucin and aggregation), functionalities ( βgalactosidase, Bile Salt hydrolase, anti-oxidants, anti-microbial substances) and capabilities (thermal and aqueous buffer stability) of L. plantarum 022AE indicating its suitability in human and animal nutrition. Conclusion The entire genome study and phenotypic evaluation exhibited a positive profile in terms of safety and probiotic attributes of L. plantarum 022AE, in alignment with current regulatory standards, suggesting its potential for use in applications requiring safe microbial strains, particularly in the food and pharmaceutical industries.

Background Increasing yield will have major implications for vaccine manufacturers. Internal bacterial contamination of specific pathogen-free (SPF) eggs results in batches of vaccines being rejected and may negatively impact vaccine yield. Objective The objectives of this study were to analyze Germ-Free (GF) eggs microbiologically and evaluate the yield of H1N1 when compared with SPF eggs from 2 different suppliers. Methods The contents of GF eggs were analyzed using three different methods (sterility test, total viable count, and bioluminescence). Eggs from each source were inoculated with H1N1 virus. Chick Embryo Fibroblast (CEF) cell cultures were generated from GF and SPF eggs from both suppliers and infected with H1N1. The supernatant was titrated for viral Haemagglutinin activity and virus infectivity while cellular RNA extracts were assayed for Interferon (α and β) gene expression by RT-qPCR using gene-specific primers. Results The analysis of GF eggs confirmed that the contents were sterile. The batch yield of GF eggs was ~1.2-fold and ~1.8-fold higher than SPF supplier 1 and SPF supplier 2 virus yields, respectively. Replication of H1N1 was 2-fold higher in CEF derived from GF eggs than CEF derived from SPF supplier 1 or SPF supplier 2. IFN-β antiviral response of GF-derived CEF cells was 2-fold lower than SPF supplier 1-derived and ~3-fold lower than SPF supplier 2-derived CEF cells. Conclusion The content of GF eggs was sterile. The yield of H1N1 was higher in GF eggs than in SPF eggs, and the higher yield was associated with a significant reduction in interferon Beta levels.

Background Nosocomial infections, a major health problem, are due at 80% to biofilm‐associated infection. Staphylococcus aureus, a prominent biofilm producer, has both MRSA and MSSA biofilm-forming capabilities that highlight its persistence in hospital environments. In previous studies, less focus was given to the components of the biofilms. Therefore, understanding biofilm composition has become crucial. Objective In this study, the components in the biofilm matrix in MRSA and MSSA isolates were estimated, and the prevalence of sdr genes (sdrC,sdrD,sdrE) among S. aureus strains was investigated. Methods Between September, 2023 and January, 2024, a total of 200 specimens were collected from patients with suspected Staphylococcus aureus infections. Eighty-two isolates were identified as S. aureus from various sources, including wounds, nasal swabs, ear swabs, and blood, based on macroscopic, microscopic, and molecular properties. Biofilms were subjected to DNase and proteinase K treatment in order to identify their biochemical composition. Multiplex PCR was used to determine the distribution of sdr genes among isolates. Results The average reduction after treatment with proteinase K in MSSA biofilms (29.67±16.62) was significantly lower than in MRSA biofilms (46.21±26.33, p=0.032). Also, when treated with DNase, MRSA biofilms showed a greater average reduction (49.65±25.30) compared to MSSA biofilms (28.71±20.98, p=0.006). MRSA and MSSA biofilms also had different polysaccharide concentrations, with MSSA biofilms having significantly higher levels (206.86±82.92 μM/OD595) than MRSA biofilms (85.80±32.52 μM/OD595, p=0.005). The sdrC gene was most common in the gene profiles of MRSA (100%) and MSSA (50%). There was a strong association between the presence of the sdrD gene and methicillin-resistant S. aureus isolates (p < 0.001). Conclusion These findings indicate that the biofilms of MRSA isolates are largely composed of proteins and eDNA, while MSSA isolates rely on polysaccharides in their biofilms. The results indicate the importance of proteins encoded by SDR genes in the development of biofilm structure.

Introduction Bacterial superinfection with Streptococcus pneumoniae following the influenza virus infection complicates the course of the disease and is a major cause of mortality during influenza virus epidemics. The effectiveness of licensed polysaccharide vaccines is limited by the serotypes included in the vaccine and possible immune tolerance during revaccination. Pneumococcal surface protein A (PspA), which includes conserved regions and has at least two functions in pathogen virulence, is considered a promising target for the development of new-generation vaccines, including gene-engineering constructions. Therefore, the development of an influenza virus vector-based vaccine expressing conserved bacterial proteins seems to be a promising strategy for designing combined vaccines against influenza and bacterial pathogens. Methods A recombinant live attenuated influenza virus (LAIV) expressing PspA fragment in a modified hemagglutinin was rescued on the A/Leningrad/134/17/57 (H2N2) backbone. This recombinant virus was assessed for its growth characteristics in vitro, as well as for its immunogenicity and protective capacity, using a mouse model of influenza-bacterial coinfection. Results The rescued recombinant LAIV/HA+PspA virus was genetically stable after sequential passaging in embryonated chicken eggs and possessed an attenuated phenotype similar to the classical LAIV strain. The LAIV/HA+PspA bivalent vaccine-induced IgG antibodies specific to both influenza virus and S. pneumoniae and provided complete protection of vaccinated mice against lethal influenza infection, as well as a 40% survival rate for lethal homologous and heterologous influenza infection complicated by concomitant bacterial infection with S. pneumoniae. Conclusion The presented design of a recombinant influenza virus carrying immunogenic fragments of a bacterial pathogen can be considered a promising strategy for the combined protection of vaccinated individuals against influenza and its bacterial complications, and further in-depth studies of such recombinant viruses in preclinical studies are warranted.

Background: A putative glycosyl hydrolase gene biof1_09 was identified from a metagenomic fosmid library of local biofertilizers in previous report [1]. The gene is renamed as gh43kk in this study. Methods: The gene gh43kk, encoding a putative β-D-xylosidase was amplified by polymerase chain reaction (PCR) and successfully cloned and expressed in Escherichia coli. The expressed recombinant protein was purified by metal affinity chromatography. Its properties were initially verified by enzyme assay and thin layer chromatography (TLC). Results: The purified recombinant protein showed the highest catalytic activities at acidic pH 4 and 50°C toward beechwood xylan, followed by carboxymethylcellulose (CMC). TLC analysis indicated a release of xylose and glucose when xylan and CMC were treated with Gh43kk protein, respectively, whereas glucose and cellobiose were detected when avicel, cellulose and filter paper were used as substrates, suggesting its dual function as xylanase with cellulase activity. The enzyme indicated great stability in a temperature between 10 to 50 °C and a wide range of pH from 4 to 8. Enzyme activity of Gh43kk was enhanced in the presence of magnesium and manganese ions, while calcium ions, Ethylenediaminetetraacetic acid (EDTA) and sodium dodecyl sulfate (SDS) inhibited the enzyme activity. Conclusion: These results suggest that Gh43kk could be a potential candidate for application in various bioconversion processes.

Introduction:Predictions on the world’s population in the next few decades suggest that the global demand for animal-derived proteins may not be met if current conventional agriculture approaches are used. One promising solution to this complex crisis lies in the use of single-cell proteins (SCP). SCP refers to the edible biomass of unicellular microorganisms and can be developed as animal feeds or human foods. This paper provides a detailed overview on research towards the production and utilisation of SCPs and trends within the field.Study Design:A bibliometric based study was conducted on 425 SCP research articles collected from the Web of Science database, analysing the most cited papers using VOSviewer software, and contributing authors, affiliations and country of origin. Research publications on SCP started in 1961 and has grown steadily over the years.Discussion:Emerging research topics within SCP production focused on the use of improved fungal strains, the composition and characteristics of SCPs based on the type of substrates used, industrial production processes and the use of waste for SCP production, which serves the dual purpose of mitigating the cost associated with waste disposal and production of a valuable product.

COVID-19 has affected millions of people, causing a burden on healthcare systems as well as economies throughout the world. Antiviral drugs do not work well enough for everyone. The mortality rate in the world is still significant. Developing safe, effective, affordable, and fast-acting vaccines for COVID-19 is critical for reducing new viral strains in this pandemic and re-establishing normality in the future. Therefore, several pharmaceutical companies are racing to develop effective vaccines for COVID-19. Scientists have developed different kinds of candidate vaccines with various platforms. By March 2021, thirteen vaccines were approved for emergency use in several countries across the world, whilst over 90 vaccine candidates were under clinical trials. There are also several vaccine candidates in Phase 3 trials awaiting results and approval for their use. These candidate vaccines revealed positive results in the previous phase trials, whereby they can induce an immune response with less adverse reaction in the participants. This review focuses on the development of COVID-19 vaccines and highlights the efficacy and adverse reactions of vaccines authorized for emergency use.

Major Histocompatibility Complex (MHC) molecules play a crucial role in inducing an adaptive immune response. T-cell epitopes require compatible MHC molecules to form MHC-peptide Complexes (pMHC) that activate the T-cell Receptors (TCR) of T-lymphocyte clones. MHCs are polymorphic molecules with wide varieties of gene alleles. There are two classes of MHC molecules, class I and II. Both classes have three classical loci HLA-A, -B, and –C are present in class I and HLA-DP, -DQ, and -DR in class II. To induce a compatible T-lymphocyte clone, the T-cell epitope requires the association of the compatible MHC molecule to form pMHC. Each MHC variant possesses a different groove that is capable of binding a different range of antigenic epitopes. Without the compatible MHC molecule, a T cell clone cannot be activated by a particular viral epitope. With the aim of preventing viral transmission, the efficiency of a viral vaccine is related to the existence of specific MHC alleles in the individual. This article proposes the roles of the MHC molecule to prevent viral infection. In addition, the association of the viral receptor molecule with the viral infection will also be discussed.

Background:Generally, about half of the patients with central nervous system infections cases remain unexplained. Therefore, we aimed to describe which viruses were detected in unselected patients with a suspected central nervous system infection and the first diagnostic workflow in a university hospital laboratory.Methods:A comprehensive virus testing in cerebrospinal fluid with an in-house real-time PCR method was employed. Determining how many and which viruses to test was at the full discretion of the treating physician.Results:1462 patients were evaluated from 2011 to 2017 and 9 898 viral PCRs were made: 176 subjects (12%) had a positive result. There was great heterogeneity in the frequency of patients tested for each virus, ranging from 97.9% (1431 out of 1462) for herpes simplex virus (HSV) to 1.9% (28 out of 1462) for Parvovirus B19, positive in 1 patient. Enterovirus (EV) was the leading virus detected: the frequency was higher with respect to HSV (5.2% vs 2.4%, p=0.0004), varicella-zoster virus (VZV)(5.2% vs 2.9%, p=0.0052), human herpesvirus-6 (5.2% vs 1.7%, p=0.0014) and human herpesvirus-7 (HHV-7)(5.2% vs 2.5%, p=0.0406). Both VZV (83.5%) and HSV (97.9%) were tested significantly more than EV (68.7%, p<0.0001) and HHV-7 (24.1%, p<0.0001): the latter had a positivity comparable to HSV and it was detected in younger patients (median age 29 years), as for EV (median age 35 years). There was no difference found in the age of positive subjects with respect to negative ones for the other viruses tested.Conclusion:EV was the fifth virus frequently included in the diagnostic workflow but the most frequently detected, mostly in subjects aged less 40, as HHV-7 was. Testing these two viruses in all younger patients could reduce the number of unknown etiology.

Objective: Water plays an important role in both domestic and commercial settings. Pathogenic microbial contaminants, however, render water unsafe for use. There are several reports on the quality of water used for drinking purposes in humans but few studies have been conducted on the microbial quality of water used in animal farming. Methods: In this study, the resistance pattern of bacterial isolates from drinking water used in poultry production in the Ashanti region of Ghana from our previously published report was determined. The presence of Escherichia coli, Salmonella typhi, Staphylococcus aureus and coagulase-negative Staphylococci was determined using selective culture media (pour plate method) and confirmed through Gram staining and biochemical reactions. Antibiotic sensitivity of isolates was determined followed by detection of Extended-Spectrum Beta-Lactamase (ESBL) producing Gram-negative isolates. Results: The study revealed that water used in poultry farms contains sources of multi-drug resistant strains of E. coli, S. typhi, S. aureus and coagulase-negative staphylococci. E. coli, S. typhi, S. aureus and coagulase-negative staphylococci were recovered from 31%, 36%, 64% and 19% of samples, respectively. Majority of these isolates were resistant to cephalosporins and penicillins. Almost 95% of the bacterial isolates were multi-drug resistant. None of E. coli and S. typhi isolates produced ESBL. Conclusion: There is a need for stringent regulations and stringent measures should be taken to make these various sources of water safe for use in animal husbandry as these waters are a potential source of pathogenic and resistant bacterial strains which can cause infections to the animals and farm workers.