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Wijnands, L. M.

Publications and source records attributed to Wijnands, L. M..

3 recordsLinked to original sources

Colon cancer and cell transformation by clinical Salmonella strains are associated with bacterial virulence and intracellular fitness

Non-typhoidal Salmonella (NTS) are facultative intracellular pathogens that are associated epidemiologically and experimentally with colon cancer development. Yet, the driving factors of Salmonella-induced cell transformation are mostly unknown. We compared 30 (case) NTS clinical strains isolated from patients who were diagnosed with colon cancer >1 year after NTS infection, versus 30 (control) strains from patients who did not develop colon cancer. While we observed diverse cell invasion and transformation efficiencies among the 60 NTS strains, case strains showed higher transformation efficiency than matching control strains. Genomic and transcriptomic analyses showed that transformation efficiency could not be attributed to specific genomic features, but was associated with gene expression, particularly metabolic genes and regulons. Moreover, high-transforming NTS strains display increased capacity to utilize various nutrient sources, including carbohydrates and amino acids, and grow significantly faster intracellularly than low-transforming NTS. Our results link NTS intracellular virulence to cancer promotion. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=198 SRC="FIGDIR/small/562874v1_ufig1.gif" ALT="Figure 1"> View larger version (51K): org.highwire.dtl.DTLVardef@137c6bcorg.highwire.dtl.DTLVardef@d874c1org.highwire.dtl.DTLVardef@d94b22org.highwire.dtl.DTLVardef@1d3e11c_HPS_FORMAT_FIGEXP M_FIG C_FIG In briefNon-typhoidal Salmonella (NTS) infections can promote cell transformation and colon cancer progression. Yet, little is known about the driving factors of Salmonella-induced transformation. Stevenin et al. performed a multi-omic characterization of clinical NTS strains identified in a nation-wide epidemiological study as associated with colon cancer and revealed a link between bacterial virulence, intracellular fitness, and host cell transformation. Highlights- Cancer-associated clinical NTS generate more cell transformation than matching control NTS. - NTS transformation efficiency did not correlate with specific genetic features. - NTS transformation efficiency correlates with gene expression and bacterial metabolic needs. - High-transforming NTS display increased virulence and intracellular fitness.

microbiology↗

Impact of bacterial microcompartment-dependent ethanolamine and propanediol metabolism on Listeria monocytogenes interactions with Caco-2 cells

Bacterial microcompartment (BMC) dependent ethanolamine (eut) and propanediol utilization (pdu) has recently been shown to stimulate anaerobic growth of Listeria monocytogenes. This metabolic repertoire conceivably contributes to the competitive fitness of L. monocytogenes in the human gastrointestinal (GI) tract, where these compounds become available following phospholipid degradation and mucus-derived rhamnose metabolism by commensal microbiota. Previous transcriptomics and mutant studies of eut and pdu L. monocytogenes suggested a possible role of eut and pdu BMC metabolism in transmission in foods and pathogenicity, but data on a potential role of L. monocytogenes interaction with human cells is currently absent. First, we ask which cellular systems are expressed in the activation of eut and pdu BMC metabolism and the extent to which these systems are conserved between the states. We find common and unique systems related to metabolic shifts, stress and virulence factors. Next, we hypothesize that these common and unique activated cellular systems contribute to a role in the interaction of L. monocytogenes interaction with human cells. We present evidence that metabolically primed L. monocytogenes with active eut and pdu BMCs, as confirmed by metabolic analysis, transmission electron microscopy and proteomics, show significantly enhanced translocation efficacy compared to non-induced cells in a trans-well assay using Caco-2 cells, while adhesion and invasion capacity was similar. Taken together, our results provide insights into the possible key cellular players that drive translocation efficacy upon eut and pdu BMC activation.

microbiology↗

Impact of vitamin B12 on rhamnose metabolism, stress defense and in-vitro virulence of Listeria monocytogenes

Listeria monocytogenes is a facultative anaerobe which can cause a severe food-borne infection known as listeriosis. Rhamnose is a deoxyhexose sugar abundant in a range of environments, including the human intestine, and can be degraded by L. monocytogenes in aerobic and anaerobic conditions into lactate, acetate and 1,2-propanediol. Our previous study showed that addition of vitamin B12 stimulates anaerobic growth of L. monocytogenes on rhamnose due to the activation of bacterial microcompartment (BMC)-dependent 1,2-propanediol utilization with concomitant production of propionate and propanol. Notably, anaerobic propanediol metabolism has been linked to virulence of enteric pathogens including Salmonella spp. and L. monocytogenes. In this study we investigate the impact of B12 on aerobic and anerobic growth of L. monocytogenes on rhamnose, and observed growth stimulation and pdu BMC activation only in anaerobically grown cells with B12 added to the medium. Comparative Caco-2 virulence assays, showed that these pdu BMC induced cells have significantly higher translocation efficiency compared to aerobically grown cells (without and with added B12) and non-induced anaerobically grown cells, while adhesion and invasion capacity is similar for all cells. Comparative proteomics analysis showed specific and overlapping responses linked to metabolic shifts, activation of stress defense proteins and virulence factors, with RNA polymerase sigma factor SigL; teichoic acids export ATP-binding protein, TagH; DNA repair and protection proteins RadA and DPS; and glutathione synthase GshAB previously linked to activation of virulence response in L. monocytogenes, uniquely upregulated in anaerobically rhamnose grown pdu BMC induced cells. Our results shed new light into B12 impact on L. monocytogenes competitive fitness and virulence.

microbiology↗