Research Publications (Food Safety)

We compared the consistency, accuracy and reproducibility of next-generation short read sequencing between ten laboratories involved in food safety (research institutes, state laboratories, universities and companies) from Germany and Austria. Participants were asked to sequence six DNA samples of three bacterial species (Campylobacter jejuni, Listeria monocytogenes and Salmonella enterica) in duplicate, according to their routine in-house sequencing protocol.

by Jun-feng Zhang, Bai Wei, Se-Yeoun Cha, Ke Shang, Hyung-Kwan Jang, Min Kang

Over the last decade, electrolyzed water (EW) produced by salt and tap water has gained importance due to its antimicrobial effects. Regarding to chlorine-based compounds, EW also used in post-harvest safety of food processing and sterilization of surfaces. The latest studies suggested that EW might act as wound healing agent due to anti-infective and cell proliferative properties.

This study investigated the prevalence, serovar distribution, antimicrobial resistance, and pulsed field gel electrophoresis (PFGE) typing of Salmonella enterica isolated from Lake Zapotlán, Jalisco, Mexico. Additionally, the association of the presence of Salmonella with physicochemical and environmental parameters was analyzed using Pearson correlation analysis and principal component analysis (PCA). Salmonella spp. were identified in 19 of 63 (30.15%) samples.

ABSTRACT

We report the complete genome sequence of P22-like Salmonella enterica serovar Typhimurium phage MG40, whose prophage repressor specificity is different from that of other known temperate phages.

Food has a major impact on all aspects of health. Recent data suggest that food composition can also affect susceptibility to infections by enteropathogenic bacteria. Here, we discuss how food may alter the microbiota as well as mucosal defenses and how this can affect infection. Salmonella Typhimurium diarrhea serves as a paradigm, and complementary evidence comes from other pathogens.

Author(s): Xingning Xiao, Wen Wang, Jianmin Zhang, Ming Liao, Chase Rainwater, Hua Yang, Yanbin Li

Author(s): Yeben Ma, Xuebin Xu, Yuan Gao, Zeqiang Zhan, Chenggang Xu, Xiaoyun Qu, Zhengquan Chen, Jie Bai, Ming Liao, Jianmin Zhang

Background Soybean meal (SBM) is the most common protein source used in the poultry and livestock industries. It has high‐quality protein, an excellent amino acid (AA) profile, and positive isoflavone properties. However, the antigen proteins in SBM are unsuitable for young animals. The objective of this study was to identify a Bacillus strain that can degrade soybean antigen proteins and evaluate the feasibility of its application in SBM fermentation.

The food-borne pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium) causes self-limiting gastroenteritis in humans and is not easily eradicated because it often attaches to suitable surfaces to form biofilms that have high resistance to disinfectants and antimicrobials. To develop an alternative strategy for the treatment of biofilms, it is necessary to further explore the effects of flagellar motility on the development process of Salmonella biofilms.

ABSTRACT

YggS (COG0325) is a pyridoxal 5'-phosphate (PLP)-binding protein proposed to be involved in homeostasis of B6 vitamers. In Salmonella enterica, lack of yggS resulted in phenotypes that were distinct, and others that were similar, to those of a yggS mutant of Escherichia coli. Like other organisms, yggS mutants of S. enterica accumulate endogenous pyridoxine 5'-phosphate (PNP). Data herein show that strains lacking YggS accumulated ~10-fold more PLP in growth medium than a parental strain.

Salmonella spp. are a major cause of foodborne illness throughout the world. Traditional serotyping by antisera agglutination has been used as a standard identification method for many years but newer nucleic acid-based tests have become available that may provide advantages in workflow and test turnaround time.

Author(s): Wannes Van Beeck, Cédric Verschueren, Sander Wuyts, Marianne F.L. van den Broek, Mieke Uyttendaele, Sarah Lebeer

The research aimed to generate an early warning system highlighting in real‐time bacterial contamination of meat matrices and providing information which could support companies in accepting or rejecting batches. Current microorganisms’ detection methods rely on techniques (plate counting), which provide retrospective values for microbial contamination.

We describe a protein secretion system in Gram‐negative bacteria that uses a holin membrane protein in tandem with a cell wall editing enzyme. The pairing of holins from different families with various types of peptidoglycan hydrolases suggests that this secretion pathway evolved multiple times. We propose that the pathway be named the Type 10 Secretion System (TXSS). Summary Gram‐negative bacteria have evolved numerous pathways to secrete proteins across their complex cell envelopes.

Seed consumption has increased in recent years because the high nutrient content of seeds. However, the number of outbreaks caused by Salmonella associated with the consumption of low water activity food items has also increased, although these food items do not support microbial growth. The main goal of this study was to quantify microbial indicators and to determine the prevalence and content of Salmonella spp. in chia, amaranth and sesame seeds obtained from Mexican retail outlets.

SYTO 9 is a fluorescent nucleic acid stain that is widely used in microbiology, particularly for fluorescence microscopy and flow cytometry analyzes. Fluorimetry-based analysis, i.e., analysis of fluorescence intensity from a bulk sample measurement, is more cost effective, rapid and accessible than microscopy or flow cytometry but requires application-specific calibration. Here we show the relevance of SYTO 9 for food safety analysis.

Salmonella enterica is an important global pathogen due to its contribution to human morbidity and death. The presence of S. enterica in Southeast Asian informal markets is amplified by cross-contamination between market surfaces and food products. Here, we describe the draft genome sequences of 81 Salmonella enterica isolates from informal markets in Cambodia.

Salmonella enterica subsp. diarizonae serovar 61:k:1,5,(7) is commonly associated with sheep. Occasionally, the serovar has been found to also infect humans. Here, we report the complete genome sequence of strain 14-SA00836-0, isolated from human urine. To our knowledge, this is the first reported complete genome sequence of this serovar isolated from a human clinical sample.

The study determined the genetic relatedness of Salmonella serotypes isolated from poultry caeca at the outlets cottage processors in Trinidad by pulsed‐field gel electrophoresis (PFGE). Of a total of 1503 caecal samples tested 91 (6.1%) yielded Salmonella spp. Ten serotypes were detected in the 91 Salmonella isolates which were digested by Xbal and subjected to PFGE.

Author(s): Ting Li, Ling Jin, Kaiwen Feng, Tan Yang, Xianglin Yue, Bin Wu, Shuangyan Ding, Xuehua Liang, Ganhui Huang, Jinsheng Zhang

Author(s): Ilkin Yucel Sengun, Gulden Kilic, Berna Ozturk

Salmonella is a leading cause of bacterial infections in animals and humans. We sequenced a collection of 450 Salmonella strains from diseased animals to better understand the genetic makeup of their virulence and resistance features. The presence of Salmonella pathogenicity islands (SPIs) varied by serotype. S. Enteritidis carried the most SPIs (n = 15), while S. Mbandaka, S. Cerro, S. Meleagridis, and S. Havana carried the least (n = 10). S. Typhimurium, S. Choleraesuis, S.