Research Publications (Food Safety)

Virulence gene expression of Yersinia pseudotuberculosis changes during the different stages of infection and this is tightly controlled by environmental cues. In this study, we show that the small protein YmoA, a member of the Hha family, is part of this process. It controls temperature- and nutrient-dependent early and later stage virulence genes in an opposing manner and co-regulates bacterial stress responses and metabolic functions.

Aerobactin is a citrate-hydroxamate siderophore that is critical for the virulence of pathogenic enteric bacteria. However, although the aerobactin-producing iucABCD-iutA operon is distributed widely in the genomes of Yersinia species, none of the pathogenic Yersinia spp. was found to produce aerobactin. Here, we showed that the iucABCD-iutA operon in the food-borne enteric pathogen Yersinia pseudotuberculosis YPIII is a functional siderophore system involved in iron acquisition.

by Pavan Patel, Brendan J. O’Hara, Emily Aunins, Kimberly M. Davis

Author(s): D. Cristiano, M.F. Peruzy, M. Aponte, A. Mancusi, Y.T.R. Proroga, F. Capuano, N. Murru

Journal of Applied Microbiology, Accepted Article. Aims
To phytosynthesize silver nanoparticles (AgNPs) and determine their antibacterial and antibiofilm capacity against gram-positive and negative bacterial strains.

Author(s): Juan Wang, Ming Liu, Huixian Wang, Qingping Wu, Yu Ding, Tianxiang Xu, Guoxiang Ma, Yueming Zhong, Jumei Zhang, Moutong Chen, Liang Xue, Qinghua Ye, Haiyan Zeng, Xiaojuan Yang, Runshi Yang

Author(s): Lu Tian, Xuyang Wang, Di Zhang, Mi Wu, Zhifei Xue, Zhiqiang Liu, Siqi Yang, Hui Li, Guoli Gong

Yersinia pseudotuberculosis is an important pathogen for both humans and animals. It can infect livestock, as well as pets and wild animals. During recent years, a number of reports have described the isolation of Y. pseudotuberculosis from zoo animals, mainly birds and mammals, for which the infection was mostly lethal. Between 2005 and 2019, there were at least 17 cases of deceased mammals, belonging to five different species, which suffered from a Y.

The outer membrane protein OmpA is a virulence factor in many mammalian pathogens. In previous global RNA structure probing studies, we found evidence for a temperature-modulated RNA structure in the 5'-untranslated region (5'-UTR) of the Yersinia pseudotuberculosis ompA transcript suggesting that opening of the structure at host-body temperature might relieve translational repression.

The foodborne pathogen Yersinia enterocolitica causes gastrointestinal infections worldwide. In the spring of 2019, the Swedish Public Health Agency and Statens Serum Institut in Denmark independently identified an outbreak caused by Yersinia enterocolitica 4/O:3 that after sequence comparison turned out to be a cross-border outbreak. A trace-back investigation suggested shipments of fresh prewashed spinach from Italy as a common source for the outbreak.

Here, we report the complete genome sequence of a Swedish clinical strain of Yersinia enterocolitica, Y72. With emerging Yersinia outbreaks circulating in Nordic countries, the Y72 genome will provide more insights on the genetic relatedness and antibiotic resistance dissemination in future studies.

Author(s): Ran Cai, Fen Gao, Junfeng Pan, Xinwei Hao, Zonglan Yu, Yichen Qu, Jialin Li, Dandan Wang, Yao Wang, Xihui Shen, Xingyu Liu, Yantao Yang

To colonize in the digestive tract of animals and humans, Yersinia pseudotuberculosis has to deal with reactive oxygen species (ROS) produced by host cells and microbiota. However, an understanding of the ROS-scavenging systems and their regulation in this bacterium remains largely elusive. In this study, we identified OxyR as the master transcriptional regulator mediating cellular responses to hydrogen peroxide (H2O2) in Y. pseudotuberculosis through genomics and transcriptomics analyses.

ABSTRACT At the intestinal host-microbe interface, the transmembrane mucin MUC1 can function as a physical barrier as well as a receptor for bacteria. MUC1 also influences epithelial cell morphology and receptor function. Various bacterial pathogens can exploit integrins to infect eukaryotic cells. It is yet unclear whether MUC1 influences the interaction of bacteria with integrins.

In July 2019, we investigated a cluster of Yersinia enterocolitica cases affecting a youth summer camp and nearby community in northeastern Pennsylvania. After initial telephone interviews with camp owners and community members, we identified pasteurized milk from a small dairy conducting on-site pasteurization, Dairy A, as a shared exposure. We conducted site visits at the camp and Dairy A where we collected milk and other samples. Samples were cultured for Y. enterocolitica.

ABSTRACT LcrF is the master regulator that positively regulates the Ysc type III secretion system (T3SS) in Yersinia and shares a high similarity with the DNA-binding domain of the T3SS master regulator ExsA in Pseudomonas aeruginosa. Based on these features, bioinformatics analysis has predicted a putative LcrF-binding site in its target promoters. Here, we experimentally characterized its binding motif.

Despite the recent advances in sequencing technologies, the complete assembly of multi-chromosome genomes of the Vibrionaceae , often containing several plasmids, remains challenging.

ABSTRACT The human pulmonary environment is complex, containing a matrix of cells, including fibroblasts, epithelial cells, interstitial macrophages, alveolar macrophages and neutrophils. When confronted with foreign material or invading pathogens, these cells mount a robust response. Nevertheless, many bacterial pathogens with an intracellular lifecycle stage exploit this environment for replication and survival.

Pathogenic Yersinia spp. depend on the activity of a potent virulence plasmid-encoded ysc/yop type 3 secretion system (T3SS) to colonize hosts and cause disease. It was recently shown that Yersinia pseudotuberculosis upregulates the virulence plasmid copy number (PCN) during infection and that the resulting elevated gene dose of plasmid-encoded T3SS genes is essential for virulence.

by Joa Braïthe Mangombi, Nadine N’dilimabaka, Jean-Bernard Lekana-Douki, Octavie Banga, Sydney Maghendji-Nzondo, Mathieu Bourgarel, Eric Leroy, Florence Fenollar, Oleg Mediannikov

Isolation of the pathogens Yersinia enterocolitica and Yersinia pseudotuberculosis from foods typically rely on slow (10–21 day) “cold enrichment” protocols before confirmed results are obtained. We describe an approach that yields results in 39 h that combines an alternative enrichment method with culture on a non-selective medium, and subsequent identification of suspect colonies using elastic light scatter (ELS) analysis.

Pneumonic plague, caused by Yersinia pestis, is a rapidly progressing bronchopneumonia involving focal bacterial growth, neutrophilic congestion, and alveolar necrosis. Within a short time after inhalation of Y. pestis, inflammatory cytokines are expressed via the Toll/interleukin-1 (IL-1) adaptor myeloid differentiation primary response 88 (MyD88), which facilitates the primary lung infection. We previously showed that Y.

Author(s): Francesca Piras, Carlo Spanu, Rita Sanna, Giuliana Siddi, Anna Maria Mocci, Mariella Demontis, Maria Pina Meloni, Vincenzo Spanu, Enrico Pietro Luigi De Santis, Christian Scarano

Cyadox has potential use as an antimicrobial agent in animals. However, its pharmacodynamic properties have not been systematically studied yet. In this study, the in vitro antibacterial activities of cyadox were assayed, and the antibacterial efficacy of cyadox against facultative anaerobes was also determined under anaerobic conditions.