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The effects of gene body DNA methylation on gene regulation still remains highly controversial. In this study, we generated whole genome bisulfite sequencing (WGBS) data with high sequencing depth in induced pluripotent stem cell (iPSC) and neuronal progentior cell (NPC), and investigated the relationship between DNA methylation changes in CpG islands (CGIs) and corresponding gene expression during NPC differentiation. Interestingly, differentially methylated CGIs were more abundant in intragenic regions compared to promoters and these methylated intragenic CGIs (iCGIs) were associated with neuronal development-related genes. When we compared gene expression level of methylated and unmethylated CGIs in intragenic regions, DNA methylation of iCGI was positively correlated with gene expression in contrast with promoter CGIs (pCGIs). To gain insight into regulatory mechanism mediated by iCGI DNA methylation, we executed motif searching in hypermethylated iCGIs and found NEUROD1 as a hypermethylated iCGI binding transcription factor. This study highlights give rise to possibility of activating role of hypermethylation in iCGIs and involvement of neuronal development related TFs. Graphical Abstract The relationship between iCGI DNA methylation and expression of associated genes in neuronal developmental process. During iPSC to NPCdifferentiation, iCGI containing neural developmental genes show iCGI’s DNA hypermethylation which is accompanied by gene activation and NEUROD1which is one of the core neuronal TFs interacts with hypermethylated iCGI regions.This chapter describes methods used to isolate, identify, and partially characterize lactic acid bacteria (LAB) which exhibit inhibitory activity against Listeria monocytogenes from foods. Vegetal (plant based) sources are rich in naturally occurring LAB and therefore provide an easily accessible source of strains with potential antimicrobial activity for use in food-processing applications. From our previous work, the majority of LAB with inhibitory activity against L. monocytogenes were identified as generally recognized as safe (GRAS) Lactococcus lactis. Although these bacteria are most commonly known for their role in industrial dairy fermentations, they are believed to have originally derived from natural plant-based habitats. These isolates with anti-Listeria activity were all found to carry the genes involved in the production of nisin, which is an approved food-grade preservative (E234). These isolates may find various applications for in situ production of nisin allowing control of L. monocytogenes in various fermented and non-fermented foods and other environments.The Listeria monitoring program for Austrian dairies and cheese factories was established in 1988. The aim was to control the entrance of L. monocytogenes into the food-processing environment (FPE), preventing the contamination of food under processing. click here monitoring program comprises four levels of investigation, dealing with routine monitoring of samples and consequences of finding a positive sample. Preventive quality control concepts attempt to detect a foodborne hazard along the food-processing chain, prior to food delivery, retailing, and consumption. The implementation of a preventive food safety concept provokes a deepened insight by the manufacturers into problems concerning food safety. The development of preventive quality assurance strategies contributes to the national food safety status and protects public health.Biofilm-forming ability may vary significantly among different Listeria (L.) monocytogenes strains. This interstrain variation is also observed in L. monocytogenes biofilm resistance to antimicrobial compounds commonly used in the food-processing environment. The screening of a large set of L. monocytogenes strains with specific characteristics, such as serotype, MLST type, and other genetic characteristics under various environmental conditions, may lead to a better understanding of the mechanisms underlying the establishment of the pathogen on food contact surfaces. In this chapter, traditional methods for L. monocytogenes strains characterization with regard to biofilm formation and novel biofilm control methods will be described.The pathogen Listeria monocytogenes is a facultative intracellular bacterium, which targets a large range of cell types. Following entry, bacteria disrupt the invasion vacuole and reach the cytoplasm where they replicate and use the actin cytoskeleton to propel themselves from cell to cell. Mammalian epithelial cells grown in vitro can be used to study the different steps of the intracellular life of Listeria. However, rapid multiplication and dissemination of bacteria can induce important cell death and detachment, resulting in the formation of lytic plaques. Thus, in vitro infections with L. monocytogenes are usually restricted to short time courses, from a few minutes to one day. Here, we present a method to study long-term L. monocytogenes infections in epithelial cells using epifluorescence microscopy. This protocol enables the observation of actin-based motility, intercellular dissemination foci, and entrapment of L. monocytogenes within vacuoles of persistence termed “Listeria-Containing Vacuoles” (LisCVs). We also describe a protocol to study the recruitment of cytoskeletal proteins at Listeria actin comet tails, as well as a method to assess the membrane integrity of intracellular bacteria using a LIVE/DEAD viability assay.Listeria monocytogenes is a model intracellular pathogen that can invade the cytoplasm of host mammalian cells. Cellular invasion can be measured using standard techniques, such as the classical gentamicin protection assay, based on the quantification of colony-forming units from lysates of infected cells. In addition, there are methods based on immunofluorescence microscopy which allow for assaying invasion in a medium- to high-throughput manner. In the following sections, we detail two different assays that can be used alone or in combination to quantify the internalization of L. #link# monocytogenes in host cells.Genes that play a role in stress response mechanisms and other phenotypes of Listeria monocytogenes can be identified by construction and screening of mutant libraries. In this chapter, we describe the construction and screening of mutant libraries of L. monocytogenes using the plasmid pMC38, carrying a mariner-based transposon system (TC1/mariner) and constructed by Cao et al. (Appl Environ Microbiol 732758-2761, 2007). Following screening of mutant libraries, putative mutants are identified and the transposon is localized, leading to identification of the genes responsible for the phenotype of interest. To confirm the role of the transposon-harboring gene in the relevant phenotype, transposon mutants are genetically complemented with the wild-type gene using the site-specific temperature-sensitive integration vector pPL2, constructed by Lauer et al. (J Bacteriol 1844177-4186, 2002).