-
Science Advances Aug 2023Circadian clocks are pervasive throughout nature, yet only recently has this adaptive regulatory program been described in nonphotosynthetic bacteria. Here, we describe...
Circadian clocks are pervasive throughout nature, yet only recently has this adaptive regulatory program been described in nonphotosynthetic bacteria. Here, we describe an inherent complexity in the circadian clock. We find that entrains to blue and red light and that circadian entrainment is separable from masking through fluence titration and frequency demultiplication protocols. We identify circadian rhythmicity in constant light, consistent with the Aschoff's rule, and entrainment aftereffects, both of which are properties described for eukaryotic circadian clocks. We report that circadian rhythms occur in wild isolates of this prokaryote, thus establishing them as a general property of this species, and that its circadian system responds to the environment in a complex fashion that is consistent with multicellular eukaryotic circadian systems.
Topics: Circadian Clocks; Bacillus subtilis; Circadian Rhythm; Light; Eukaryota
PubMed: 37540742
DOI: 10.1126/sciadv.adh1308 -
Toxins Jan 2024Institut Pasteur and have enjoyed a relationship lasting almost 120 years, starting from its foundation and the pioneering work of Louis Pasteur in the nascent fields... (Review)
Review
Institut Pasteur and have enjoyed a relationship lasting almost 120 years, starting from its foundation and the pioneering work of Louis Pasteur in the nascent fields of microbiology and vaccination, and blooming after 1986 following the molecular biology/genetic revolution. This contribution will give a historical overview of these two research eras, taking advantage of the archives conserved at Institut Pasteur. The first era mainly focused on the production, characterisation, surveillance and improvement of veterinary anthrax vaccines; the concepts and technologies with which to reach a deep understanding of this research field were not yet available. The second period saw a new era of research at Institut Pasteur, with the anthrax laboratory developing a multi-disciplinary approach, ranging from structural analysis, biochemistry, genetic expression, and regulation to bacterial-host cell interactions, pathogenicity, and therapy development; this led to the comprehensive unravelling of many facets of this toxi-infection. may exemplify some general points on how science is performed in a given society at a given time and how a scientific research domain evolves. A striking illustration can be seen in the additive layers of regulations that were implemented from the beginning of the 21st century and their impact on research. and anthrax are complex systems that raise many valuable questions regarding basic research. One may hope that research will be re-initiated under favourable circumstances later at Institut Pasteur.
Topics: Humans; Bacillus anthracis; Anthrax; Charcoal; Bacterial Toxins; Virulence; Antigens, Bacterial
PubMed: 38393144
DOI: 10.3390/toxins16020066 -
Microbiome Sep 2023The microbiota of the upper respiratory tract is increasingly recognized as a gatekeeper of respiratory health. Despite this, the microbiota of healthy adults remains...
BACKGROUND
The microbiota of the upper respiratory tract is increasingly recognized as a gatekeeper of respiratory health. Despite this, the microbiota of healthy adults remains understudied. To address this gap, we investigated the composition of the nasopharyngeal and oropharyngeal microbiota of healthy adults, focusing on the effect of Streptococcus pneumoniae carriage, smoking habits, and contact with children.
RESULTS
Differential abundance analysis indicated that the microbiota of the oropharynx was significantly different from that of the nasopharynx (P < 0.001) and highly discriminated by a balance between the classes Negativicutes and Bacilli (AUC of 0.979). Moreover, the oropharynx was associated with a more homogeneous microbiota across individuals, with just two vs. five clusters identified in the nasopharynx. We observed a shift in the nasopharyngeal microbiota of carriers vs. noncarriers with an increased relative abundance of Streptococcus, which summed up to 30% vs. 10% in noncarriers and was not mirrored in the oropharynx. The oropharyngeal microbiota of smokers had a lower diversity than the microbiota of nonsmokers, while no differences were observed in the nasopharyngeal microbiota. In particular, the microbiota of smokers, compared with nonsmokers, was enriched (on average 16-fold) in potential pathogenic taxa involved in periodontal diseases of the genera Bacillus and Burkholderia previously identified in metagenomic studies of cigarettes. The microbiota of adults with contact with children resembled the microbiota of children. Specifically, the nasopharyngeal microbiota of these adults had, on average, an eightfold increase in relative abundance in Streptococcus sp., Moraxella catarrhalis, and Haemophilus influenzae, pathobionts known to colonize the children's upper respiratory tract, and a fourfold decrease in Staphylococcus aureus and Staphylococcus lugdunensis.
CONCLUSIONS
Our study showed that, in adults, the presence of S. pneumoniae in the nasopharynx is associated with a shift in the microbiota and dominance of the Streptococcus genus. Furthermore, we observed that smoking habits are associated with an increase in bacterial genera commonly linked to periodontal diseases. Interestingly, our research also revealed that adults who have regular contact with children have a microbiota enriched in pathobionts frequently carried by children. These findings collectively contribute to a deeper understanding of how various factors influence the upper respiratory tract microbiota in adults. Video Abstract.
Topics: Adult; Child; Humans; Streptococcus pneumoniae; Smoking; Nose; Microbiota; Metagenome; Bacillus; Firmicutes
PubMed: 37658443
DOI: 10.1186/s40168-023-01640-9 -
Scientific Reports Aug 2023The Middle Atlas is a Moroccan territory that serves as an abode to plants with incredible biodiversity, of which aromatic and medicinal plants that have been of...
The Middle Atlas is a Moroccan territory that serves as an abode to plants with incredible biodiversity, of which aromatic and medicinal plants that have been of folkloric use are a significant component. However, their effective utilization in modern medicine requires the characterization of their phytochemicals to facilitate their entry into drug discovery pipelines. Hence, this study aimed to characterize and investigate the antioxidant activity and antimicrobial effects of the essential oils (EOs) of Salvia lavandulifolia subsp. mesatlantica and Salvia officinalis L. by use of in vitro and in silico assays. Ten phytochemicals were identified in the EOs of S. lavandulifolia, while twenty phytochemicals were identified in S. officinalis. Camphor was the most abundant compound in both species, comprising 26.70% and 39.24% of the EOs of S. lavandulifolia and S. officinalis, respectively. The EOs of both plants exhibited significant DPPH free radical scavenging activity, with S. lavandulifolia and S. officinalis showing estimated scavenging rates of 92.97% and 75.20%, respectively. In terms of Ferric Reducing Antioxidant Power (FRAP), S. officinalis demonstrated a higher value (72.08%) compared to that of S. lavandulifolia (64.61%). Evaluation of the antimicrobial effects of the EOs of S. officinalis and S. lavandulifolia against microorganisms revealed bactericidal activities against Proteus mirabilis and Bacillus subtilis at low concentrations. It showed bactericidal activities against Staphylococcus aureus and Candida albicans at a relatively higher concentration. Molecular docking of antioxidant and antimicrobial proteins offers significant insights into ligand-protein interactions, facilitating the development of innovative therapeutics from the current study. Ultimately, this study identified the phytochemical composition of S. lavandulifolia and S. officinalis and highlighted their potential for therapeutic discovery.
Topics: Oils, Volatile; Antioxidants; Molecular Docking Simulation; Camphor; Bacillus subtilis
PubMed: 37640782
DOI: 10.1038/s41598-023-41178-2 -
Applied Microbiology and Biotechnology Dec 2024Bacillus anthracis is an etiological agent of anthrax, a severe zoonotic disease that can be transmitted to people and cause high mortalities. Bacteriophages and their...
Bacillus anthracis is an etiological agent of anthrax, a severe zoonotic disease that can be transmitted to people and cause high mortalities. Bacteriophages and their lytic enzymes, endolysins, have potential therapeutic value in treating infections caused by this bacterium as alternatives or complements to antibiotic therapy. They can also be used to identify and detect B. anthracis. Endolysins of two B. anthracis Wbetavirus phages, J5a and F16Ba which were described by us recently, differ significantly from the best-known B. anthracis phage endolysin PlyG from Wbetavirus genus bacteriophage Gamma and a few other Wbetavirus genus phages. They are larger than PlyG (351 vs. 233 amino acid residues), contain a signal peptide at their N-termini, and, by prediction, have a different fold of cell binding domain suggesting different structural basis of cell epitope recognition. We purified in a soluble form the modified versions of these endolysins, designated by us LysJ and LysF, respectively, and depleted of signal peptides. Both modified endolysins could lyse the B. anthracis cell wall in zymogram assays. Their activity against the living cells of B. anthracis and other species of Bacillus genus was tested by spotting on the layers of bacteria in soft agar and by assessing the reduction of optical density of bacterial suspensions. Both methods proved the effectiveness of LysJ and LysF in killing the anthrax bacilli, although the results obtained by each method differed. Additionally, the lytic efficiency of both proteins was different, which apparently correlates with differences in their amino acid sequence. KEY POINTS: • LysJ and LysF are B. anthracis-targeting lysins differing from lysins studied so far • LysJ and LysF could be overproduced in E. coli in soluble and active forms • LysJ and LysF are active in killing cells of B. anthracis virulent strains.
Topics: Humans; Bacillus anthracis; Bacteriophages; Anthrax; Escherichia coli; Bacillus
PubMed: 38194144
DOI: 10.1007/s00253-023-12839-z -
Applied Microbiology and Biotechnology Jan 2024The application of enzymes is expanding across diverse industries due to their nontoxic and biodegradable characteristics. Another advantage is their cost-effectiveness,... (Review)
Review
The application of enzymes is expanding across diverse industries due to their nontoxic and biodegradable characteristics. Another advantage is their cost-effectiveness, reflected in reduced processing time, water, and energy consumption. Although Gram-positive bacteria, Bacillus, and Streptomyces spp. are successfully used for production of industrially relevant enzymes, they still lag far behind Escherichia coli as hosts for recombinant protein production. Generally, proteins secreted by Bacillus and Streptomyces hosts are released into the culture medium; their native conformation is preserved and easier recovery process enabled. Given the resilience of both hosts in harsh environmental conditions and their spore-forming capability, a deeper understanding and broader use of Bacillus and Streptomyces as expression hosts could significantly enhance the robustness of industrial bioprocesses. This mini-review aims to compare two expression hosts, emphasizing their specific advantages in industrial surroundings such are chemical, detergent, textile, food, animal feed, leather, and paper industries. The homologous sources, heterologous hosts, and molecular tools used for the production of recombinant proteins in these hosts are discussed. The potential to use both hosts as biocatalysts is also evaluated. Undoubtedly, Bacillus and Streptomyces spp. as production hosts possess the potential to take on a more substantial role, providing superior (bio-based) process robustness and flexibility. KEY POINTS: • Bacillus and Streptomyces spp. as robust hosts for enzyme production. • Industrially relevant enzyme groups for production in alternative hosts highlighted. • Molecular biology techniques are enabling easier utilization of both hosts.
Topics: Animals; Bacillus; Animal Feed; Biological Transport; Culture Media; Escherichia coli
PubMed: 38289383
DOI: 10.1007/s00253-023-12900-x -
Journal of Photochemistry and... Jul 2023As a new kind of modern military biological weapon, bacterial agents pose a serious threat to the public health security of human beings. Existing bacterial...
As a new kind of modern military biological weapon, bacterial agents pose a serious threat to the public health security of human beings. Existing bacterial identification requires manual sampling and testing, which is time-consuming, and may also introduce secondary contamination or radioactive hazards during decontamination. In this paper, a non-contact, nondestructive and "green" bacterial identification and decontamination technology based on laser-induced breakdown spectroscopy (LIBS) is proposed. The principal component analysis (PCA) combined with support vector machine (SVM) based on radial basis kernel function is used to establish the classification model of bacteria, and the two-dimensional decontamination test of bacteria is carried out using laser-induced low-temperature plasma combined with a vibration mirror. The experimental results show that the average identification rate of the seven types of bacteria, including Escherichia coli, Bacillus subtilis, Pseudomonas fluorescens, Bacillus megatherium, Pseudomonas aeruginosa, Bacillus thuringiensis and Enterococcus faecalis reaches 98.93%, and the corresponding true positive rate, precision, recall and F1-score reaches 0.9714, 0.9718, 0.9714 and 0.9716, respectively. The optimal decontamination parameters are laser defocusing amount of -50 mm, laser repetition rate of 15-20 kHz, scanning speed of 150 mm/s and number of scans of 10. In this way, the decontamination speed can reach 25.6 mm/min, and the inactivation rates for both Escherichia coli and Bacillus subtilis are higher than 98%. In addition, it is confirmed that the inactivation rate of plasma is 4 times higher than that of thermal ablation, meaning that the decontamination ability of LIBS mainly relies on the plasma rather than the thermal ablation effect. The new non-contact bacterial identification and decontamination technology does not require sample pretreatment, and can quickly identify bacteria in situ and decontaminate the surfaces of precision instruments, sensitive materials, etc., which has potential application value in modern military, medical and public health fields.
Topics: Humans; Decontamination; Bacillus subtilis; Spectrum Analysis; Lasers; Escherichia coli
PubMed: 37201319
DOI: 10.1016/j.jphotobiol.2023.112719 -
MSystems Aug 2023is a soil-dwelling bacterium that can form biofilms, or communities of cells surrounded by a self-produced extracellular matrix. In biofilms, genetically identical...
is a soil-dwelling bacterium that can form biofilms, or communities of cells surrounded by a self-produced extracellular matrix. In biofilms, genetically identical cells often exhibit heterogeneous transcriptional phenotypes, so that subpopulations of cells carry out essential yet costly cellular processes that allow the entire population to thrive. Surprisingly, the extent of phenotypic heterogeneity and the relationships between subpopulations of cells within biofilms of even in well-studied bacterial systems like remains largely unknown. To determine relationships between these subpopulations of cells, we created 182 strains containing pairwise combinations of fluorescent transcriptional reporters for the expression state of 14 different genes associated with potential cellular subpopulations. We determined the spatial organization of the expression of these genes within biofilms using confocal microscopy, which revealed that many reporters localized to distinct areas of the biofilm, some of which were co-localized. We used flow cytometry to quantify reporter co-expression, which revealed that many cells "multi-task," simultaneously expressing two reporters. These data indicate that prior models describing cells as differentiating into specific cell types, each with a specific task or function, were oversimplified. Only a few subpopulations of cells, including surfactin and plipastatin producers, as well as sporulating and competent cells, appear to have distinct roles based on the set of genes examined here. These data will provide us with a framework with which to further study and make predictions about the roles of diverse cellular phenotypes in biofilms. IMPORTANCE Many microbes differentiate, expressing diverse phenotypes to ensure their survival in various environments. However, studies on phenotypic differentiation have typically examined only a few phenotypes at one time, thus limiting our knowledge about the extent of differentiation and phenotypic overlap in the population. We investigated the spatial organization and gene expression relationships for genes important in biofilms. In doing so, we mapped spatial gene expression patterns and expanded the number of cell populations described in the literature. It is likely that other bacteria also display complex differentiation patterns within their biofilms. Studying the extent of cellular differentiation in other microbes may be important when designing therapies for disease-causing bacteria, where studying only a single phenotype may be masking underlying phenotypic differentiation relevant to infection outcomes.
Topics: Bacillus subtilis; Biofilms; Microscopy, Confocal; Flow Cytometry; Cell Differentiation
PubMed: 37527273
DOI: 10.1128/msystems.00891-22 -
Applied and Environmental Microbiology Jul 2023This study aimed to elaborate the assembly processes and metabolic regulation of the microbial community under the conditions of environmental factors and artificial...
This study aimed to elaborate the assembly processes and metabolic regulation of the microbial community under the conditions of environmental factors and artificial intervention using broad bean paste (BBP) fermentation as a tractable research object. Spatial heterogenicity of amino acid nitrogen, titratable acidity, and volatile metabolites were observed between upper and lower layers after fermentation for 2 weeks. Amino nitrogen contents in the upper fermented mash reached 0.86, 0.93, and 1.06 g/100 g at 2, 4, and 6 weeks, respectively, which were significantly higher than those of mash located at the lower layer (0.61, 0.79, and 0.78 g/100 g). Moreover, higher concentrations of titratable acidity were accumulated in upper layers (2.05, 2.25 and 2.56 g/100g) than those in lower layers, and the differentiation of volatile metabolites was the greatest ( = 0.543) at 36 days, after which the BBP flavor profiles converged with the fermentation progress. The successive heterogenicity of the microbial community in the mid-late stage was also found during fermentation, and Zygosaccharomyces, Staphylococcus, and had heterogeneous characteristics driven by sunlight, water activity, and microbial interactions. This study provided new insights into the mechanisms underlying the succession and assembly of the microbial community of BBP fermentation, which also laid new clues for researches of the microbial communities in complex ecosystems. Gaining insights into the community assembly processes is essential and valuable for the elaboration of underlying ecological patterns. However, current studies about microbial community succession in multispecies fermented food usually treat the research object as a whole, are focused exclusively on temporal dimensions, and have ignored the changes of community structure in spatial dimensions. Therefore, dissecting the community assembly process from the view of spatiotemporal dimensions will be a more comprehensive and detailed perspective. Here, we found the heterogenicity of the BBP microbial community under the traditional production technology from spatial and temporal scales, systematically analyzed the relationship between the spatiotemporal succession of community and the difference of BBP quality, and elucidated the roles of environmental factors and microbial interactions to drive the heterogeneous succession of the microbial community. Our findings provide a new insight into understanding the association between microbial community assembly and the quality of BBP.
Topics: Bacteria; Fermentation; Microbiota; Bacillus; Microbial Interactions
PubMed: 37306603
DOI: 10.1128/aem.00621-23 -
Scientific Reports Oct 2023Currently, there are numerous methods that can be used to neutralize pathogens (i.e., devices, tools, or protective clothing), but the sterilizing agent must be selected...
Currently, there are numerous methods that can be used to neutralize pathogens (i.e., devices, tools, or protective clothing), but the sterilizing agent must be selected so that it does not damage or change the properties of the material to which it is applied. Dry sterilization with hydrogen peroxide gas (VHP) in combination with UV-C radiation is well described and effective method of sterilization. This paper presents the design, construction, and analysis of a novel model of sterilization device. Verification of the sterilization process was performed, using classical microbiological methods and flow cytometry, on samples containing Geobacillus stearothermophilus spores, Bacillus subtilis spores, Escherichia coli, and Candida albicans. Flow cytometry results were in line with the standardized microbiological tests and confirmed the effectiveness of the sterilization process. It was also determined that mobile sterilization stations represent a valuable solution when dedicated to public institutions and businesses in the tourism sector, sports & fitness industry, or other types of services, e.g., cosmetic services. A key feature of this solution is the ability to adapt the device within specific constraints to the user's needs.
Topics: Sterilization; Geobacillus stearothermophilus; Bacillus subtilis; Hydrogen Peroxide; Spores; Spores, Bacterial
PubMed: 37833295
DOI: 10.1038/s41598-023-44483-y