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Cystic Fibrosis (CF) occurs as a result of mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which lead to misfolding, trafficking defects, and impaired function of the CFTR protein. Splicing factor proline/glutamine-rich (SFPQ) is a multifunctional nuclear RNA-binding protein (RBP) implicated in the regulation of gene expression pathways and intracellular trafficking. Here, we investigated the role of SFPQ in the regulation of the expression and function of F508del-CFTR in CF lung epithelial cells. We find that the expression of SFPQ is reduced in F508del-CFTR CF epithelial cells compared to WT-CFTR control cells. Interestingly, the overexpression of SFPQ in CF cells increases the expression as well as rescues the function of F508del-CFTR. Further, comprehensive transcriptome analyses indicate that SFPQ plays a key role in activating the mutant F508del-CFTR by modulating several cellular signaling pathways. This is the first report on the role of SFPQ in the regulation of expression and function of F508del-CFTR in CF lung disease. Our findings provide new insights into SFPQ-mediated molecular mechanisms and point to possible novel epigenetic therapeutic targets for CF and related pulmonary diseases.

Nutrient procurement specifically from nutrient-limiting environment is essential for pathogenic bacteria to survive and/or persist within the host. Long-term survival or persistent infection is one of the main reasons for the overuse of antibiotics, and contributes to the development and spread of antibiotic resistance. Mycobacterium tuberculosis is known for long-term survival within the host, and develops multidrug resistance. Before and during infection, the pathogen encounters various harsh environmental conditions. To cope up with such nutrient-limiting conditions, it is crucial to uptake essential nutrients such as ions, sugars, amino acids, peptides, and metals, necessary for numerous vital biological activities. Among the various types of transporters, ATP-binding cassette (ABC) importers are essentially unique to bacteria, accessible as drug targets without penetrating the cytoplasmic membrane, and offer an ATP-dependent gateway into the cell by mimicking substrates of the importer and designing inhibitors against substrate-binding proteins, ABC importers endeavour for the development of successful drug candidates and antibiotics. Alternatively, the production of antibodies against substrate-binding proteins could lead to vaccine development. In this review, we will emphasize the role of M. tuberculosis ABC importers for survival and virulence within the host. Furthermore, we will elucidate their unique characteristics to discover emerging therapies to combat tuberculosis.

Coronavirus disease 2019 (COVID-19) is a viral illness caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is a worsening global pandemic. COVID-19 has caused at least 1.7 million deaths worldwide and over 300,000 in the United States. Recently, two promising vaccines are being administered in several countries. However, there remains an urgent need for a therapeutic treatment for COVID-19 patients with severe respiratory damage that can lead to intensive care, prolonged hospitalization, or mortality. Moreover, an increasing population of patients manifest lingering disabling symptoms (called Long Haulers). Here, we tested the efficacy of a recombinant neural epidermal growth factor like 1 protein variant (NELL1-NV1) in a COVID-19 mouse model, transgenic mice expressing the human angiotensin I-converting enzyme 2 (ACE2) receptor (tg-mice hACE2) infected with SARS-CoV-2. The administration of NELL1-NV1 to SARS-CoV-2-infected tg-mice hACE2 significantly improved clinical health score and increased survival. Analyses of bronchoalveolar (BAL) fluid demonstrated decreased levels of several cytokines and chemokines (IFN-γ, IL-10, IL-12 p70, CXCL-10/IP-10, MIG and Rantes), in NV1-treated treated mice compared to controls. Cytokines including IL-1α, IL-9, IL-6, LIX/CXCL5, KC/CXCL1, MIP-2/CXCL2, MIP-1α/CCL3, and G-CSF, critical to immune responses such as neutrophil recruitment, viral clearance and vascularization, were increased compared to controls. Our data suggest the potential of NELL1-NV1-based therapy to mitigate the cytokine storm, modulate the abnormal immune response and repair respiratory tissue damage in COVID-19 patients.

With the advancement in transcriptomic technology, it is now possible to get insights into undescribed phenomena of the continually evolving arms race of plant–pathogen interactions. The study of this interaction describes various mechanisms such as the plant defense pathway, regulatory gene annotation, gene network, and biochemical metabolism of plants and pathogens, which still remain a major challenge in agriculture. Researchers can understand the mechanisms of altering gene expression during compatible and incompatible interaction of pathogenic organisms at the molecular level. Transcriptome profiling could efficiently identify the differential changes in gene expression in response to infection, and thereby provide information regarding the basal defense system, resistance, pathogenicity of plant pathogens, and the difference between host and nonhost defense mechanisms of plants. Based on this information, several broad spectrum disease-resistant crop plants have been generated.

Coronavirus disease 2019 (COVID-19) is a recent global pandemic. It is a deadly human viral disease, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with a high rate of infection, morbidity and mortality. Therefore, there is a great urgency to develop new therapies to control, treat and prevent this disease. Endogenous microRNAs (miRNAs, miRs) of the viral host are key molecules in preventing viral entry and replication, and building an antiviral cellular defense. Here, we have analyzed the role of miR-155, one of the most powerful drivers of host antiviral responses including immune and inflammatory responses, in the pathogenicity of SARS-CoV-2 infection. Subsequently, we have analyzed the potency of anti-miR-155 therapy in a COVID-19 mouse model (mice transgenic for human angiotensin I-converting enzyme 2 receptor (tg-mice hACE2)). We report for the first time that miR-155 expression is elevated in COVID-19 patients. Further, our data indicate that the viral load as well as miR-155 levels are higher in male relative to female patients. Moreover, we find that the delivery of anti-miR-155 to SARS-CoV-2-infected tg-mice hACE2 effectively suppresses miR-155 expression, and leads to improved survival and clinical scores. Importantly, anti-miR-155-treated tg-mice hACE2 infected with SARS-CoV-2 not only exhibit reduced levels of pro-inflammatory cytokines, but also have increased anti-viral and anti-inflammatory cytokine responses in the lungs. Thus, our study suggests anti-miR-155 as a novel therapy for mitigating the lung cytokine storm induced by SARS-CoV-2 infection.

Endophytes are microorganisms residing inside the plants with an escalating interest for the scientific community. The plethora of endophyte-derived medicinal molecules and the application potentials in agriculture and bioremediation are some of the reasons why endophytes are extensively studied. Endophytes which can be either endophytic fungi or bacteria have been isolated from a wide variety of plants. The huge diversity among the endophytic microbes and the host plants hinders the establishment of a uniform protocol for isolation of endophytes. However, the most common technique that is currently used involves a thorough surface sterilization followed by fragmentation of the plant tissue and culture of the fragments onto agar plates. Nevertheless, non-culturable microorganisms are usually omitted from the aforementioned procedure and molecular approaches have to be applied for a more inclusive isolation. Sequencing of 16S rRNA for bacteria and ITS or 18S rRNA for fungi can be applied to both culturable and unculturable endophytes. Sometimes, morphological examination can be a further validation for the identification of the isolated strains. Subsequently, a variety of biochemical and molecular approaches including colorimetry, spot assays, chromatographies, and gene-targeted PCR (polymerase chain reaction) amplification are performed in order to further characterize the endophytic strains. Scrutinous functional analysis of endophytes may provide valuable insights into the advancement of agriculture, medicine, and industry. In this chapter, methods for the isolation of endophytic bacteria/fungi, identification, and their characterization depending on their functional role are discussed and provided as a helpful toolbox for a new researcher in the endophyte field.

The early detection of Listeria monocytogenes (L. monocytogenes) and understanding the disease burden is of paramount interest. The failure to detect pathogenic bacteria in the food industry may have terrible consequences, and poses deleterious effects on human health. Therefore, integration of methods to detect and trace the route of pathogens along the entire food supply network might facilitate elucidation of the main contamination sources. Recent research interest has been oriented towards the development of rapid and affordable pathogen detection tools/techniques. An innovative and new approach like biosensors has been quite promising in revealing the foodborne pathogens. In spite of the existing knowledge, advanced research is still needed to substantiate the expeditious nature and sensitivity of biosensors for rapid and in situ analysis of foodborne pathogens. This review summarizes recent developments in optical, piezoelectric, cell-based, and electrochemical biosensors for Listeria sp. detection in clinical diagnostics, food analysis, and environmental monitoring, and also lists their drawbacks and advantages.

Listeria monocytogenes has emerged as the deadly pathogen inflicting high mortality in humans and animals. To investigate the strain-specific characteristics of L. monocytogenes , and their role(s) in virulence and ecological sustenance, we sequenced genome of three L. monocytogenes strains BHU1, 2 and 3 isolated from the Ganges river, agricultural soil and human placenta bit, respectively, and compared it with L. monocytogenes EGD-e serovar 1/2a and L. monocytogenes F2365 serovar 4b strain. The contigs of all the three strains had a similarity (> 90%) in regions that aligned with EGD-e and F2365. A total of 2872 core genes on the set of strains were identified in BHU1, 2 and 3 strains. In the mice virulence assay, BHU2 and 3 strains showed pathogenicity while BHU1 was non-pathogenic. These strains were also characterized with unique genes (8 genes in BHU1, 12 in BHU 2, and 17 in BHU 3 strain). Phylogenetic analysis based on multilocus sequence typing revealed BHU1, 2 and 3 strains to be more closely related to lineage I, serotype 4b, clonal complex 1, and sequence type 328. BHU1 strain seemed to harbor nucleotide mutation from A to G in the major virulence genes i.e. hemolysin D and listeriolysin O. Strain-specific mutations 8, 5 and 2 were identified in BHU1, 2 and 3, respectively, compared to F2365. Though all the three strains were genetically very close, the observed differences may play the crucial role(s) in their virulence attributes, and also, in the prevalence of L. monocytogenes .

Infectious diseases are life-threatening and may lead to high mortality and morbidity rates. The existing danger of an increase and spread of multidrug resistance pathogens is a global concern. Therefore, the designing of novel antibiotics and vaccine to control and eliminate the disease is an utmost requirement. Traditional approaches for screening vaccine and drug targets are time-consuming and have been unsuccessful in controlling the spread of infectious diseases due to several reasons such as altered antigenic diversity, altered virulence potential, and antimicrobial resistance in the infectious agent population. To overcome this problem, there has been a paradigm shift from the conventional to microbial genomics approaches, as the availability of complete genome sequence of pathogenic microorganisms and multiple isolates of the same species provides a wealth of information on nearly all the potential drug targets. Microbial genomics approaches open up new avenues to pursuit novel antimicrobial agents that are highly conserved in a range of microbes, essential for the survival of pathogens and absent in humans. In this chapter, we present an overview of the microbial genomics approaches such as pan-genomics, comparative genomics, functional genomics, structural genomics, transcriptomics, and proteomics used in the discovery and development of novel antibiotics.

The discrimination between Listeria monocytogenes and Listeria species has been detected. The 16S rRNA and hlyA were PCR amplified with set of oligonucleotide primers with flank 1,500 and 456 bp fragments, respectively. Based on the differences in 16S rRNA and hlyA genes, a total 80 isolates from different environmental, food and clinical samples confirmed it to be L. monocytogenes. The 16S rRNA sequence similarity suggested that the isolates were similar to the previously reported ones from different habitats by others. The phylogenetic interrelationships of the genus Listeria were investigated by sequencing of 16S rRNA and hlyA gene. The 16S rRNA sequence indicated that genus Listeria is comprised of following closely related but distinct lines of descent, one is the L. monocytogenes species group (including L. innocua, L. ivanovii, L. seeligeri and L. welshimeri) and other, the species L. grayi, L. rocourtiae and L. fleischmannii. The phylogenetic tree based on hlyA gene sequence clearly differentiates between the L. monocytogenes, L. ivanovii and L. seeligeri. In the present study, we identified 80 isolates of L. monocytogenes originating from different clinical, food and environmental samples based on 16S rRNA and hlyA gene sequence similarity.

Human listeriosis caused by Listeria monocytogenes (LM) is a serious public health concern. The disease leads to several health issues like abortion, stillbirth, septicaemia, meningitis and meningoencephalitis. The main targets are pregnant women, neonates, elderly or immunocompromised people 1 .

Listeria monocytogenes, a life-threatening pathogen, poses severe risk during pregnancy, may cause abortion, fetal death or neonatal morbidity in terms of septicemia and meningitis. The present study aimed at characterizing L. monocytogenes isolated from pregnant women based on serotyping, antibiotic susceptibility, virulence genes, in vivo pathogenicity test and ERIC- and REP-PCR fingerprint analyses. The results revealed that out of 3700 human clinical samples, a total of 30 (0.81%) isolates [12 (0.80%) from placental bit (1500), 18 (0.81%) from vaginal swab (2200)] were positive for L. monocytogenes. All the isolates belonged to serogroup 4b, and were + ve for virulence genes tested i.e. inlA, inlC, inlJ, plcA, prfA, actA, hlyA, and iap. Based on the mice inoculation tests, 20 isolates showed 100% and 4 isolates 60% relative virulence while 6 isolates were non-pathogenic. Moreover, 2 and 10 isolates were resistant to ciprofloxacin and cefoxitin, respectively, while the rest susceptible to other antibiotics used in this study. ERIC- and REP-PCR collectively depicted that the isolates from placental bit and vaginal swab had distinct PCR fingerprints except a few isolates with identical patterns. This study demonstrates prevalence of pathogenic strains mostly resistant to cefoxitin and/or ciprofloxacin. The results indicate the importance of isolating and characterizing the pathogen from human clinical samples as the pre-requisite for accurate epidemiological investigations.

We present here the whole-genome sequences of Listeria monocytogenes from Ganges River water, agricultural soil, and human clinical samples from Varanasi, India, which will be used for a comparative analysis.

Listeria monocytogenes is a life threatening pathogenic bacteria concerned with human health. The accurate and rapid detection of L. monocytogenes is required for preventing of listeriosis. In this study, DNA sensing probe based on conducting polymer poly-5-carboxy indole (5C Pin) was developed for the detection of L. monocytogenes hlyA gene responsible for pathogenicity. The probe sequences (24 mer ssDNA) were covalently immobilized on 5C Pin via N-(3-dimethylaminopropyl)-N′-ethylcarbodiimidehydrochloride (EDC) and N-hydroxysuccinimide (NHS). The probe having ssDNA was further hybridized with the target DNA sequence. Electrochemical impedance spectroscopic study was carried out to determine the extent of DNA hybridization over the probe. Significant change was observed in the impedance spectra before and after hybridization of ssDNA immobilized over the probe with the target DNA. RCT (charge transfer resistance) was estimated from the Nyquist plot (impedance plot) for target DNA (hlyA gene) in the solution. RCT vs. logarithmic concentrations of the target (genomic) DNA plot showed a linear range (1 × 10−4 to 1 × 10−12 M) in case hybridization was performed under optimized conditions. The method proposed, is simple, free from any label, and highly sensitive for the detection of L. monocytogenes in environmental and clinical samples.

Background Listeria monocytogenes, a foodborne pathogen is ubiquitous to different environments including the agroecosystem. The organism poses serious public health problem. Therefore, an attempt has been made to gain further insight to their antibiotic susceptibility, serotypes and the virulence genes. Results Out of the 10 vegetables selected, 6 (brinjal, cauliflower, dolichos-bean, tomato, chappan-kaddu and chilli), 20 isolates (10%) tested positive for L. monocytogenes. The prevalence of the pathogen in the respective rhizosphere soil samples was 5%. Noticeably, L. monocytogenes was absent from only cabbage, broccoli, palak and cowpea, and also the respective rhizospheric soils. The 30 isolates + ve for pathogenicity, belonged to serogroup 4b, 4d or 4e, and all were positive for inlA, inlC, inlJ, plcA, prfA, actA, hlyA and iap gene except one (VC3) among the vegetable isolates that lacked the plcA gene. ERIC- and REP-PCR collectively revealed that isolates from vegetables and their respective rhizospheric soils had distinct PCR fingerprints. Conclusions The study demonstrates the prevalence of pathogenic L. monocytogenes in the selected agricultural farm samples. The increase in the number of strains resistant to ciprofloxacin and/or cefoxitin seems to pose serious public health consequences.

Listeria monocytogenes isolated from Ganges water, human clinical and milk samples were characterized by antibiotic susceptibility, serotype identification, detection of virulence genes and ERIC- and REP-PCR fingerprint analyses. All isolates were uniformly resistant to ampicillin, except two isolates, and showed variable resistance to gentamicin, cotrimoxazole, ofloxacin, rifampicin and tetracycline. Of the 20 isolates found positive for pathogens, seven (four human and three water isolates) belong to serogroups 4b, 4d and 4e; six (one human and five water isolates) belong to serogroups 1/2c and 3c; four milk isolates belong to serogroups 1/2b and 3b; and three milk isolates belong to serogroups 1/2a and 3a. Two water isolates, all human isolates, except one (Pb1) lacking inlJ gene, and three milk isolates possess inlA, inlC, plcA, prfA, actA, hlyA and iap genes. The remaining water and milk isolates showed variable presence of inlJ, plcA, prfA, and iap genes. ERIC- and REP-PCR based analyses collectively indicated that isolates of human clinical samples belong to identical or similar clone and isolates of water and milk samples belong to different clones. Overall study demonstrates the prevalence of pathogenic L. monocytogenes species in the environmental and clinical samples. Most of the isolates were resistant to commonly used antibiotics.