Nucleic acid-based biotechnologies for food-borne pathogen detection using routine time-intensive culture-based methods and fast molecular diagnostics.

Diseases caused by food-borne pathogens constitute a major burden to consumers, food business operators, and national governments. Bacterial and viral pathogens are the major biotic factors influencing food safety. A vast array of culture dependent analytical methods and protocols have been developed.

Cellular Proteins Act as Bridge Between 5' and 3' Ends of the Coxsackievirus B3 Mediating Genome Circularization During RNA Translation.

The positive single-stranded RNA genome of the Coxsackievirus B3 (CVB3) contains a 5' untranslated region (UTR) which hosts the internal ribosome entry site (IRES) element that governs cap-independent translation initiation and a polyadenylated 3' UTR which is required for stimulating the IRES activity. Viral RNA genomes could circularize to regulate initiation of translation and RNA synthesis at 5' and 3' ends. Interactions could either take place by direct RNA-RNA contacts, through cellular protein bridges mediating RNA circularization or both.

Neutralizing activity induced by the attenuated coxsackievirus B3 Sabin3-like strain against CVB3 infection.

Coxsackievirus B3 (CVB3) causes viral myocarditis, and can ultimately result in dilated cardiomyopathy. There is no vaccine available for clinical use. In the present work, we assessed whether the Sabin3-like mutant of CVB3 could induce a protective immunity against virulent CVB3 Nancy and CVB4 E2 strains in mice by both oral and intraperitoneal (IP) routes.

Enteroviral central nervous system infections in children of the region of monastir, Tunisia: diagnosis, laboratory findings of cerebrospinal fluid and clinical manifestations.

Human enteroviruses (HEV) are one of the major causes of central nervous system (CNS) infections in pediatrics. A prospective study was conducted to assess the epidemiological, clinical, and laboratory characteristics of enterovirus (EV) infections of the CNS in children under 15-years-old, suspected of having viral CNS infections and admitted to the Pediatric Department of Monastir University Hospital, Tunisia. Enteroviral RNA was detected by 5' NCR nested RT-PCR assay in 33 % (20 out of 60) of cerebrospinal fluid specimens, whereas only six samples (10 %) were EV positive in cell culture.

Impaired binding of standard initiation factors eIF3b, eIF4G and eIF4B to domain V of the live-attenuated coxsackievirus B3 Sabin3-like IRES--alternatives for 5'UTR-related cardiovirulence mechanisms.

Unlabelled: Internal ribosome entry site (IRES) elements fold into highly organized conserved secondary and probably tertiary structures that guide the ribosome to an internal site of the RNA at the IRES 3'end. The composition of the cellular proteome is under the control of multiple processes, one of the most important being translation initiation. In each poliovirus Sabin vaccine strain, a single point mutation in the IRES secondary-structure domain V is a major determinant of neurovirulence and translation attenuation.

Role of RNA structure motifs in IRES-dependent translation initiation of the coxsackievirus B3: new insights for developing live-attenuated strains for vaccines and gene therapy.

Internal ribosome entry site (IRES) elements are highly structured RNA sequences that function to recruit ribosomes for the initiation of translation. In contrast to the canonical cap-binding, the mechanism of IRES-mediated translation initiation is still poorly understood. Translation initiation of the coxsackievirus B3 (CVB3), a causative agent of viral myocarditis, has been shown to be mediated by a highly ordered structure of the 5' untranslated region (5'UTR), which harbors an IRES.

Molecular Analysis of RNA-RNA Interactions between 5' and 3' Untranslated Regions during the Initiation of Translation of a Cardiovirulent and a Live-Attenuated Coxsackievirus B3 Strains.

Coxsackievirus B3 (CVB3) is a causative agent of viral myocarditis, meningitis and pancreatitis. CVB3 overcome their host cells by usurping the translation machinery to benefit viral gene expression. This is accomplished through alternative translation initiation in a cap independent manner at the viral internal ribosomal entry site.

Ribosomal Initiation Complex Assembly within the Wild-Strain of Coxsackievirus B3 and Live-Attenuated Sabin3-like IRESes during the Initiation of Translation.

Coxsackievirus B3 (CVB3) is an enterovirus of the family of Picornaviridae. The Group B coxsackieviruses include six serotypes (B1 to B6) that cause a variety of human diseases, including myocarditis, meningitis, and diabetes. Among the group B, the B3 strain is mostly studied for its cardiovirulence and its ability to cause acute and persistent infections.

In vitro molecular characterization of RNA-proteins interactions during initiation of translation of a wild-type and a mutant Coxsackievirus B3 RNAs.

Translation initiation of Coxsackievirus B3 (CVB3) RNA is directed by an internal ribosome entry site (IRES) within the 5' untranslated region. Host cell factors involved in this process include some canonical translation factors and additional RNA-binding proteins. We have, previously, described that the Sabin3-like mutation (U475 → C) introduced in CVB3 genome led to a defective mutant with a serious reduction in translation efficiency.

Prolonged viral RNA detection in the central nervous system of one-week-old Swiss albino mice following coxsackievirus B4 and echovirus 9 infection.

Objectives: Type B coxsackieviruses (CV-B), together with echoviruses (E), are among the most common pathogens encountered in aseptic meningitis and meningoencephalitis. They frequently infect the central nervous system (CNS). The mechanisms of virus spreading in the CNS are poorly understood.

Molecular analysis of the role of IRES stem-loop V in replicative capacities and translation efficiencies of Coxsackievirus B3 mutants.

Coxsackievirus B3 (CVB3) is a principal viral cause of acute myocarditis in humans and has been implicated in the pathogenesis of dilated cardiomyopathy. The natural genetic determinants of cardiovirulence for CVB3 have not been identified, although using strains engineered in the laboratory, it has been demonstrated elsewhere that, for several wild-type CB3 strains, the primary molecular determinant of cardiovirulence phenotype localizes to the 5' nontranslated region (5'NTR) and capsid. Stable RNA tetraloop motifs are found frequently in biologically active RNAs.

The substitution U475 --> C with Sabin3-like mutation within the IRES attenuate Coxsackievirus B3 cardiovirulence.

The Sabin3 mutation in the viral RNA plays an important role in directing attenuation phenotype of Sabin vaccine strain of poliovirus type 1 (PV1). We previously described that Sabin3-like mutation introduced in Coxsackievirus B3 (CVB3) genome led to a defective mutant. However, this mutation do not led to destruction of secondary structure motif C within the stem-loop V of CVB3 RNA because of the presence of one nucleotide difference (C --> U) in the region encompassing the Sabin3 mutation at nucleotides 471 of PV1 and 475 of CVB3 RNA.

Role of GNRA motif mutations within stem-loop V of internal ribosome entry segment in coxsackievirus B3 molecular attenuation.

The lengthy 5' nontranslated region of coxsackievirus B3 (CVB3) forms a highly ordered secondary structure containing an internal ribosome entry segment (IRES), which plays an important role in controlling viral translation and pathogenesis. The stem-loop V (SL-V) of this IRES contains a large lateral bulge loop which encompasses two conserved GNRA motifs. In this study, we analyzed the effects of point mutations within the GNRA motifs of the CVB3 IRES.

Effects of the Sabin-like mutations in domain V of the internal ribosome entry segment on translational efficiency of the Coxsackievirus B3.

The domain V within the internal ribosome entry segment (IRES) of poliovirus (PV) is expected to be important in its own neurovirulence because it contains an attenuating mutation in each of the Sabin vaccine strains. In this study, we try to find out if the results observed in the case of Sabin vaccine strains of PV can be extrapolated to another virus belonging to the same genus of enteroviruses but with a different tropism. To test this hypothesis, we used the coxsackievirus B3 (CVB3), known to be the most common causal agent of viral myocarditis.