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The Daily Star 

A few days ago around noon, rickshaw puller Abdus Salam dropped a passenger near Khamarbari intersection and stepped off his vehicle in front of a tea stall. He told the street vendor to give him a piece of bread and some tea.

While gulping the bread, the man in his late 20s asked for a glass of water. The tea seller poured some water from a jar placed on a table and handed the glass over to him. Salam drank the water believing it was filtered and safe. The vendor had the same belief.

They were probably wrong. The water was most likely to be hazardous. In fact, it might have contained fecal coliform, a bacterium found in human excreta.

A government study has revealed that almost all such jar water sold across the capital carries risky level of the bacterium, also called fecal E. coli.

The presence of E. coli indicates that other pathogenic bacteria and viruses, responsible for diseases like cholera, typhoid, dysentery and jaundice, may also be found in the water, health experts say.

The study found 1 to more than 1,600 MPN (most probable number) of E. coli in a 100-millilitre sample of drinking water. According to BSTI standards, it was supposed to be zero, says the paper of the study conducted by Bangladesh Agricultural Research Council (Barc).

Wiley Online

The present study tested antibacterial activity of a rice hull smoke extract (RHSE) against a multidrug-resistant strain of Salmonella Typhimurium and examined its mode of suppressive action in vitro and in mice. In vitro studies showed that the minimum inhibitory concentration (MIC) value of RHSE was 1.29% (v/v). The inactivation was confirmed by complete loss of cell viability in the range of 10⁴ to 10⁷ colony forming units of the resistant Salmonella Typhimurium strain. Agarose and sodium dodecyl sulfate–polyacrylamide gel electrophoreses were used to evaluate the integrities of bacterial genomic DNA and total cellular protein profiles. The antibacterial action of RHSE results from a leakage of intracellular macromolecules following rupture of bacterial cells. Scanning electron microscopy of the cells shows that RHSE also induced deleterious morphological changes in the bacterial cell membrane of the pathogens. In vivo antibacterial activity of RHSE at a 1 × MIC concentration was examined in a bacterial gastroenteritis model using Balb/c mice orally infected with the Salmonella Typhimurium. The results show greatly decreased excretion of the bacteria into the feces and suppressed translocation of the bacteria to internal organs (cecum, mesenteric lymph node, spleen, and liver) compared with the infected mice not subjected to the RHSE treatment. Collectively, the present findings indicate that the mechanism of the antibacterial activities both in vitro and in the gastroenteritis environment of the animal model is the result of the direct disruption of cell structure, leading to cell death. RHSE has the potential to serve as a multifunctional food additive that might protect consumers against infections by antibiotic-resistant microorganisms.

Nature.com

Bacterial cell–cell signalling, or quorum sensing, is characterized by the secretion and groupwide detection of small diffusible signal molecules called autoinducers. This mechanism allows cells to coordinate their behaviour in a density-dependent manner. A quorum-sensing cell may directly respond to the autoinducers it produces in a cell-autonomous and quorum-independent manner, but the strength of this self-sensing effect and its impact on bacterial physiology are unclear. Here, we explore the existence and impact of self-sensing in the Bacillus subtilis ComQXP and Rap-Phr quorum-sensing systems. By comparing the quorum-sensing response of autoinducer-secreting and non-secreting cells in co-culture, we find that secreting cells consistently show a stronger response than non-secreting cells. Combining genetic and quantitative analyses, we demonstrate this effect to be a direct result of self-sensing and rule out an indirect regulatory effect of the autoinducer production genes on response sensitivity. In addition, self-sensing in the ComQXP system affects persistence to antibiotic treatment. Together, these findings indicate the existence of self-sensing in the two most common designs of quorum-sensing systems of Gram-positive bacteria.

Penn State Food Blog

Posters – Food Safety and Sanitary Practices

Genomea

Complete genome sequences of Campylobacter coli strains WA333, YF2105, BG2108, MG1116, and BP3183 and Campylobacter jejuni strain IF1100 isolated from retail chicken liver showed the presence of 1,841,551-, 1,687,232-, 1,695,638-, 1,665,146-, 1,695,360-, and 1,744,171-bp circular chromosomes, respectively. These isolates also contained plasmids ranging in size from 5,209 to 55,122 bp.

high prevalence (77%) of Campylobacter jejuni and Campylobacter coli has been reported in retail chicken and beef liver samples (1, 2). A multistate outbreak of C. jejuni associated with undercooked chicken livers occurred in the United States in 2012 (3). A chicken liver-associated foodborne outbreak caused by Campylobacter spp. was reported in Liverpool, United Kingdom (4). Another study in the United Kingdom showed high survival rates of Campylobacter spp. in undercooked chicken livers at restaurants (5). Multilocus sequence typing showed similarities between Campylobacter strains isolated from chicken livers and those causing human illnesses (6, 7). The prevalence of plasmids has been reported to be high in Campylobacter strains isolated from retail chicken liver (8). Other foodborne pathogens, such as Staphylococcus aureus, were also reported to be prevalent in retail beef and chicken livers (9, 10).

Here, we announce the complete genome sequences of five C. coli and one C. jejuni chicken liver isolates. These isolates were previously isolated from retail chicken liver (1). The genomic and plasmid DNA was isolated from a 72-h liquid culture using a DNeasy blood and tissue kit (Qiagen, Inc., Valencia, CA) and plasmid midikit (Qiagen, Inc.). The genome sequencing was performed using the Illumina MiSeq desktop sequencer by applying the Illumina v2 reagent kit. Library preparation was performed using the Nextera XT sample preparation kit (Illumina, Inc., San Diego, CA). Assembly of the chromosomes and plasmids was carried out using CLC genomic workbench and its microbial genome finishing module (Qiagen, Inc.).

Food Standards Agency

Product details

Product: Taste the Difference 4 pack Aberdeen Angus British Beef Quarter Pounders (Frozen)

Pack size: 454g

Batches with ‘Best Before’ dates: July 2018, September 2018 and October 2018

No other Sainsbury’s products are known to be affected.

Risk

Sainsbury’s is recalling the above batches because a small number of customers have become unwell with E. coli O157 after consuming the product.

It is possible that E. coli O157 may be present in the batches listed above.

Symptoms caused by this organism include diarrhoea, abdominal pain, bloody diarrhoea, and haemolytic uremic syndrome, a serious condition that can lead to kidney failure and can be fatal.

Our advice to consumers

If you have bought any of the above batches do not eat them. Instead, return it to the store from where it was bought for a full refund.

Action taken by the company

Sainsbury’s is recalling the above product. Point of sale notices will be displayed in all retail stores that are selling this product. These notices explain to customers why the product is being recalled and tell them what to do if they have bought the product. Please see the attached notice.

Related media

FSA-PRIN-44-2017 – Sainsburys recalls Aberdeen Angus Bristish Beef Quarter Pounders(187.88 KB)

Nature .Com

The evolutionary pressure imposed by phage predation on bacteria and archaea has resulted in the development of effective anti-phage defence mechanisms, including restriction–modification and CRISPR–Cas systems. Here, we report on a new defence system, DISARM (defence island system associated with restriction–modification), which is widespread in bacteria and archaea. DISARM is composed of five genes, including a DNA methylase and four other genes annotated as a helicase domain, a phospholipase D (PLD) domain, a DUF1998 domain and a gene of unknown function. Engineering the Bacillus paralicheniformis 9945a DISARM system into Bacillus subtilis has rendered the engineered bacteria protected against phages from all three major families of tailed double-stranded DNA phages. Using a series of gene deletions, we show that four of the five genes are essential for DISARM-mediated defence, with the fifth (PLD) being redundant for defence against some of the phages. We further show that DISARM restricts incoming phage DNA and that the B. paralicheniformis DISARM methylase modifies host CCWGG motifs as a marker of self DNA akin to restriction–modification systems. Our results suggest that DISARM is a new type of multi-gene restriction–modification module, expanding the arsenal of defence systems known to be at the disposal of prokaryotes against their viruses.

Penn State Food Blog

A study published in Eurosurveillence discusses the investigation of a prolonged outbreak of Salmonella Typhimurium associated with a restaurant.  Over a period of a year, there were 82 cases (72 confirmed, 10 possible).   The issue comes down to that Salmonella had built up in the drain system, and with leaks as well as potential bio-aerosols from the drain, Salmonella was able to continue transmission into the food preparation environment.

“We found the drains had failed in several places and hypothesised that a reservoir of bacteria in biofilm [15] and flooded areas in underfloor cavities may have sustained this outbreak, after repeated environmental cleaning failed. Drainage problems in one area of the kitchen led to liquid from the drains seeping into the kitchen suggesting a contamination pathway. We found isolates matching the outbreak strain on kitchen cloths, swabs from kitchen sinks, and pot wash areas suggesting contact with sinks may have provided a second contamination pathway. We also identified ineffective drain water-traps potentially allowing the movement of contaminated bio-aerosols [13]. Smoke tests demonstrated the potential for dissemination of foul air [bio-aerosols] into the kitchen.”

Leakage from drains, backflow from drains, and perhaps even bio-aerosols from drains may be a source of contamination into a food environment.  It is important to put in procedures in place to prevent drain relates contamination.

Eurosurveillence
http://www.eurosurveillance.org/content/10.2807/1560-7917.ES.2017.22.49.17-00037#f1
Surveillance and outbreak report Open Access
http://instance.metastore.ingenta.com/content/10.2807/1560-7917.ES.2017.22.49.17-00037