Wastewater-associated plastispheres: A hidden habitat for microbial pathogens?

Wastewater treatment plants (WWTPs) receive wastewater from various sources. Despite wastewater treatment aiming to remove contaminants, microplastics persist. Plastic surfaces are quickly colonized by microbial biofilm ("plastispheres").

High-Quality Genomic DNA Extraction Protocol for Bacillus and Clostridium Species.

High-quality DNA with sufficient yield is the goal of DNA extraction protocols. We present an optimized, cost-effective method for extracting next-generation sequencing (NGS)-quality genomic DNA from Bacillus and Clostridium species using the chloroform-isoamyl approach. The protocol involves two main procedures: cultivation of the bacteria under appropriate conditions, followed by DNA extraction through cell lysis, phase separation, DNA precipitation, and cleanup.

The role of endospore appendages in spore-spore interactions in the pathogenic Bacillus cereus group.

Species within the Bacillus cereus sensu lato group, known for their spore-forming ability, are recognized for their significant role in food spoilage and food poisoning. The spores of B. cereus are adorned with numerous pilus-like appendages, referred to as S-ENAs and L-ENAs.

Helical ultrastructure of the L-ENA spore aggregation factor of a Bacillus paranthracis foodborne outbreak strain.

In pathogenic Bacillota, spores can form an infectious particle and can take up a central role in the environmental persistence and dissemination of disease. A poorly understood aspect of spore-mediated infection is the fibrous structures or 'endospore appendages' (ENAs) that have been seen to decorate the spores of pathogenic Bacilli and Clostridia. Current methodological approaches are opening a window on these long enigmatic structures.

Two-year investigation of spore-formers through the production chain at two cheese plants in Norway.

Spore-forming bacteria are the most complex group of microbes to eliminate from the dairy production line due to their ability to withstand heat treatment usually used in dairy processing. These ubiquitous microorganisms have ample opportunity for multiple points of entry into the milk chain, creating issues for food quality and safety. Certain spore-formers, namely bacilli and clostridia, are more problematic to the dairy industry due to their possible pathogenicity, growth, and production of metabolites and spoilage enzymes.

Transcriptomic and proteomic analysis of the virulence inducing effect of ciprofloxacin on enterohemorrhagic Escherichia coli.

Enterohemorrhagic E. coli (EHEC) is considered to be the most dangerous pathotype of E. coli, as it causes severe conditions such as hemorrhagic colitis (HC) and hemolytic uremic syndrome (HUS).

Freshwater plastispheres as a vector for foodborne bacteria and viruses.

There is growing evidence that plastic particles can accumulate microorganisms that are pathogenic to humans or animals. In the current study, the composition of the plastispheres that accumulated on polypropylene (PP), polyvinyl chloride (PVC), and high-density polyethylene (HDPE) pieces submerged in a river in the southeast Norway was characterized by 16S rRNA amplicon sequencing. Seasonal and geographical effects on the bacterial composition of the plastisphere were identified, in addition to the detection of potential foodborne pathogenic bacteria and viruses as part of the plastisphere.

Endospore pili: Flexible, stiff, and sticky nanofibers.

Species belonging to the Bacillus cereus group form endospores (spores) whose surface is decorated with micrometers-long and nanometers-wide endospore appendages (Enas). The Enas have recently been shown to represent a completely novel class of Gram-positive pili. They exhibit remarkable structural properties making them extremely resilient to proteolytic digestion and solubilization.

A molecular epidemiological study on Escherichia coli in young chicks with colibacillosis identified two possible outbreaks across farms.

Avian pathogenic Escherichia coli (APEC) is the cause of colibacillosis outbreaks in young poultry chicks, resulting in acute to peracute death. The high morbidity and mortality caused by colibacillosis results in poor animal welfare, reduced sustainability and economical loss worldwide. To advance the understanding of the molecular epidemiology, genomic relatedness and virulence traits of APEC, we performed systematic sampling from 45 confirmed colibacillosis broiler flocks with high first week mortality (FWM) during 2018-2021.

The Ability of Shiga Toxin-Producing to Grow in Raw Cow's Milk Stored at Low Temperatures.

Despite the lack of scientific evidence, some consumers assert that raw milk is a natural food with nutritional and immunological properties superior to pasteurized milk. This has led to the increased popularity of unpasteurized cow milk (UPM) and disregard for the risks of being exposed to zoonotic infections. Dairy cattle are healthy carriers of Shiga toxin (Stx)-producing E.

High diversity in the regulatory region of Shiga toxin encoding bacteriophages.

Background: Enterohemorrhagic Escherichia coli (EHEC) is an emerging health challenge worldwide and outbreaks caused by this pathogen poses a serious public health concern. Shiga toxin (Stx) is the major virulence factor of EHEC, and the stx genes are carried by temperate bacteriophages (Stx phages). The switch between lysogenic and lytic life cycle of the phage, which is crucial for Stx production and for severity of the disease, is regulated by the CI repressor which maintain latency by preventing transcription of the replication proteins.

High sequence similarity between avian pathogenic E. coli isolates from individual birds and within broiler chicken flocks during colibacillosis outbreaks.

Avian pathogenic E. coli (APEC) cause high first week mortality (FWM) in broiler chickens worldwide. In order to investigate the epidemiologic aspects of colibacillosis in broiler flocks it is important to develop reliable and cost-effective sampling guidelines.

The prevalence of Campylobacter spp., Listeria monocytogenes and Shiga toxin-producing Escherichia coli in Norwegian dairy cattle farms: A comparison between free stall and tie stall housing systems.

Aims: This study explored how dairy farm operating systems with free-stall or tie-stall housing and cow hygiene score influence the occurrence of zoonotic bacteria in raw milk.

Methods And Results: Samples from bulk tank milk (BTM), milk filters, faeces, feed, teats and teat milk were collected from 11 farms with loose housing and seven farms with tie-stall housing every second month over a period of 11 months and analysed for the presence of STEC by culturing combined with polymerase chain reaction and for Campylobacter spp. and L.

Whole-Genome Sequencing Analysis of Listeria monocytogenes from Rural, Urban, and Farm Environments in Norway: Genetic Diversity, Persistence, and Relation to Clinical and Food Isolates.

Listeria monocytogenes is a ubiquitous environmental bacterium associated with a wide variety of natural and human-made environments, such as soil, vegetation, livestock, food processing environments, and urban areas. It is also among the deadliest foodborne pathogens, and knowledge about its presence and diversity in potential sources is crucial to effectively track and control it in the food chain. Isolation of L.

Enigmatic Pilus-Like Endospore Appendages of Group Species.

The endospores (spores) of many sensu lato species are decorated with multiple hair/pilus-like appendages. Although they have been observed for more than 50 years, all efforts to characterize these fibers in detail have failed until now, largely due to their extraordinary resilience to proteolytic digestion and chemical solubilization. A recent structural analysis of endospore appendages (Enas) using cryo-electron microscopy has revealed the structure of two distinct fiber morphologies: the longer and more abundant "Staggered-type" (S-Ena) and the shorter "Ladder-like" type (L-Ena), which further enabled the identification of the genes encoding the S-Ena.

Replication Region Analysis Reveals Non-lambdoid Shiga Toxin Converting Bacteriophages.

Shiga toxin is the major virulence factor of enterohemorrhagic (EHEC), and the gene encoding it is carried within the genome of Shiga toxin-converting phages (Stx phages). Numerous Stx phages have been sequenced to gain a better understanding of their contribution to the virulence potential of EHEC. The Stx phages are classified into the lambdoid phage family based on similarities in lifestyle, gene arrangement, and nucleotide sequence to the lambda phages.

Characterization of Bacillus cereus sensu lato isolates from milk for consumption; phylogenetic identity, potential for spoilage and disease.

This study addresses the biodiversity of Bacillus cereus group population present along the value chain of milk for consumption. The B. cereus population did not grow and remained mainly unaltered during storage of milk at 4 °C while storage at a suboptimal temperature at 8 °C (representative of a broken cold chain) caused a major shift in its composition.

Vitamin K Analogs Influence the Growth and Virulence Potential of Enterohemorrhagic Escherichia coli.

Enterohemorrhagic (EHEC) causes serious foodborne disease worldwide. It produces the very potent Shiga toxin 2 (Stx2). The Stx2-encoding genes are located on a prophage, and production of the toxin is linked to the synthesis of Stx phages.

Culture dependent and independent analyses suggest a low level of sharing of endospore-forming species between mothers and their children.

Spore forming bacteria comprise a large part of the human gut microbiota. However, study of the endospores in gut microbiota is limited due to difficulties of culturing and numerous unknown germination factors. In this study we propose a new method for culture-independent characterization of endospores in stool samples.

Exposure to Broad-Spectrum Visible Light Causes Major Transcriptomic Changes in EGDe.

, the causative agent of the serious foodborne disease listeriosis, can rapidly adapt to a wide range of environmental stresses, including visible light. This study shows that exposure of the EGDe strain to low-intensity, broad-spectrum visible light inhibited bacterial growth and caused altered multicellular behavior during growth on semisolid agar compared to when the bacteria were grown in complete darkness. These light-dependent changes were observed regardless of the presence of the blue light receptor (Lmo0799) and the stressosome regulator sigma B (SigB), which have been suggested to be important for the ability of to respond to blue light.

Importance of Individual Germination Receptor Subunits in the Cooperative Function between GerA and Ynd.

Germination of spores is triggered by the binding of specific nutrients to germinant receptors (GRs) located in the spore's inner membrane. The GRs typically consist of A, B, and C subunits, encoded by tricistronic operons. The genome contains the family operons , , and In contrast to the ABC(D) organization that characterizes operons of many species, genomes contain a pentacistronic operon comprising the , , , , and genes encoding A, B, B, C, and B GR subunits, respectively (subscripts indicate paralogs).

Biochemical and mutational analysis of spore cortex-lytic enzymes in the food spoiler Bacillus licheniformis.

Bacillus licheniformis is frequently associated with food spoilage due to its ability to form highly resistant endospores. The present study reveals that B. licheniformis spore peptidoglycan shares a similar structure to spores of other species of Bacillus.