Background: To decipher the mechanisms underlying the protective role of the Mediterranean diet (MED) in Crohn's disease (CD), we explored the implications of adherence to MED on CD course, inflammatory markers, microbial and metabolite composition.
Methods: Patients with newly diagnosed CD were recruited and followed prospectively. MED adherence was assessed by repeated food frequency questionnaires (FFQ), using a predefined IBDMED score, alongside validated MED adherence screeners.
Cheater viruses cannot replicate on their own yet replicate faster than the wild type (WT) when the 2 viruses coinfect the same cell. Cheaters must possess dual genetic features: a defect, which leads to their inability to infect cells on their own, and a selective advantage over WT during coinfection. Previously, we have discovered 2 point-mutant cheaters of the MS2 bacteriophage.
View Article and Find Full Text PDFClustered regularly interspaced short palindromic repeats (CRISPR)-Cas (CRISPR-associated proteins) systems provide acquired heritable protection to bacteria and archaea against selfish DNA elements, such as viruses. These systems must be tightly regulated because they can capture DNA fragments from foreign selfish elements, and also occasionally from self-chromosomes, resulting in autoimmunity. Most known species from the halophilic archaeal genus contain type I-B CRISPR-Cas systems, and the strongest hotspot for self-spacer acquisition by was a locus that contained a putative transposable element, as well as the gene , which was a very frequent target for self-targeting spacers.
View Article and Find Full Text PDFSeveral studies show that gut microbiotas in patients with nonalcoholic fatty liver disease (NAFLD) differ from those in a healthy population, suggesting that this alteration plays a role in NAFLD pathogenesis. We investigated whether prebiotic administration affects liver fat content and/or liver-related and metabolic parameters. Patients with NAFLD and metabolic syndrome (age: 50 ± 11; 79% men) were randomized to receive either 16 g/day of prebiotic (ITFs-inulin-type fructans) ( = 8) or placebo (maltodextrin) ( = 11) for 12 weeks.
View Article and Find Full Text PDFIn this study, we use pan-genomics to characterize the genomic variability of the widely dispersed halophilic archaeal species ). We include a multi-regional sampling of newly sequenced, high-quality draft genomes. The pan-genome graph of the species reveals 50 genomic islands that represent rare accessory genetic capabilities available to members.
View Article and Find Full Text PDFThe gill tissue of bivalve mollusks hosts rich symbiotic microbial communities that may contribute to host health. is an invasive Lessepsian oyster in the Eastern Mediterranean Sea that has become highly abundant while constantly expanding its range northwestward. Using 16S rRNA gene amplicon sequencing, we examined how temperature affects oysters and their gill microbiota in a series of experiments: exposing them to the current annual seawater temperature range, to the colder temperature of the Western Mediterranean Sea, and to the elevated temperature as predicted under global warming scenarios.
View Article and Find Full Text PDFInteins are mobile genetic elements that invade conserved genes across all domains of life and viruses. In some instances, a single gene will have several intein insertion sites. In Haloarchaea, the minichromosome maintenance (MCM) protein at the core of replicative DNA helicase contains four intein insertion sites within close proximity, where two of these sites (MCM-a and MCM-d) are more likely to be invaded.
View Article and Find Full Text PDFSun exposure is harmful to the skin and increases the risk of skin aging and skin cancer. Here we examined the effects of daily exposure to sun radiation on the skin microbiome in order to determine whether skim microbiome bacteria can contribute to protection from solar damage. Skin swabs were collected from ten lifeguards before and after the summer to analyse the skin microbiome.
View Article and Find Full Text PDFBackground: The gut microbiome might play a role in neurodevelopment, however, evidence remains elusive. We aimed to examine the relationship between the intestinal microbiome and cognitive development of school-age children.
Methods: This cross-sectional study included healthy Israeli Arab children from different socioeconomic status (SES).
CRISPR-Cas systems provide heritable acquired immunity against viruses to archaea and bacteria. Cas3 is a CRISPR-associated protein that is common to all Type I systems, possesses both nuclease and helicase activities, and is responsible for degradation of invading DNA. Involvement of Cas3 in DNA repair had been suggested in the past, but then set aside when the role of CRISPR-Cas as an adaptive immune system was realized.
View Article and Find Full Text PDFThe Dead Sea is a salt lake with surface water at about 430 m below sea level and considered the lowest place on Earth. The Dead Sea basin is characterized by relatively high temperatures, attenuated UV radiation and the air above it has a relatively high-salt aerosol content. When we compared the skin microbiome of individuals from the hot, salty and arid Dead Sea area with that of individuals from the humid Mediterranean regions we observed a significantly lower bacterial diversity in the Dead Sea group as well as distinct differences in the composition of bacterial species.
View Article and Find Full Text PDFMetagenomics has improved our understanding of commensal bacteria that colonize human intestines yet relies almost exclusively on fecal samples. Thus, spatial information about the niche range of these gut microbes and the level of specialized adaptation that they undergo has been inaccessible to fecal metagenomic studies. Here, we leveraged metagenomic data obtained through colonoscopy aspirates from three intestinal sites of healthy adults, and reconstructed metagenome-assembled genomes of several common gut bacteria to address intestinal site-specific evolution.
View Article and Find Full Text PDFViroids and viroid-like covalently closed circular (ccc) RNAs are minimal replicators that typically encode no proteins and hijack cellular enzymes for replication. The extent and diversity of viroid-like agents are poorly understood. We developed a computational pipeline to identify viroid-like cccRNAs and applied it to 5,131 metatranscriptomes and 1,344 plant transcriptomes.
View Article and Find Full Text PDFPolyploidy, the phenomenon of having more than one copy of the genome in an organism, is common among haloarchaea. While providing short-term benefits for DNA repair, polyploidy is generally regarded as an "evolutionary trap" that by the notion of the Muller's ratchet will inevitably conclude in the species' decline or even extinction due to a gradual reduction in fitness. In most reported cases of polyploidy in archaea, the genetic state of the organism is considered as homoploidy i.
View Article and Find Full Text PDFType VI secretion systems are molecular syringes used by Gram-negative bacteria to kill heterospecific (non-kin) niche competitors. In this issue of Cell, Mashruwala et al. show that colonies of the pathogen Vibrio cholera can also exhibit T6SS-mediated cell killing of kin cells and that this process benefits emerging resistant mutants, thereby increasing genetic diversity.
View Article and Find Full Text PDFThe Mediterranean diet (MED) is associated with the modification of gut microbial composition. In this pilot study, we investigate the feasibility of a microbiota-targeted MED-based lifestyle intervention in healthy subjects. MED intervention integrating dietary counseling, a supporting mobile application, and daily physical activity measurement using step trackers was prospectively applied for 4 weeks.
View Article and Find Full Text PDFHigh-throughput RNA sequencing offers broad opportunities to explore the Earth RNA virome. Mining 5,150 diverse metatranscriptomes uncovered >2.5 million RNA virus contigs.
View Article and Find Full Text PDFHere, we examined the skin microbiome of two groups of healthy volunteers living on the Mediterranean coast with different exposures to sun radiation. One group, exposed to the sun in the summer, was compared with a group covered with clothing throughout the year. The seasonal effects on the skin microbiome of three body sites were determined before and after summer.
View Article and Find Full Text PDFViruses are important ecological, biogeochemical, and evolutionary drivers in every environment. Upon infection, they often cause the lysis of the host cell. However, some viruses exhibit alternative life cycles, such as chronic infections without cell lysis.
View Article and Find Full Text PDFAnnu Rev Microbiol
September 2022
Archaea remains the least-studied and least-characterized domain of life despite its significance not just to the ecology of our planet but also to the evolution of eukaryotes. It is therefore unsurprising that research into horizontal gene transfer (HGT) in archaea has lagged behind that of bacteria. Indeed, several archaeal lineages may owe their very existence to large-scale HGT events, and thus understanding both the molecular mechanisms and the evolutionary impact of HGT in archaea is highly important.
View Article and Find Full Text PDFBackground And Aims: Escherichia coli is over-abundant in the gut microbiome of patients with inflammatory bowel disease [IBD]. Here, we aimed to identify IBD-specific genomic functions of diverse E. coli lineages.
View Article and Find Full Text PDFThe development of the gut microbiome occurs mainly during the first years of life; however, little is known on the role of environmental and socioeconomic exposures, particularly within the household, in shaping the microbial ecology through childhood. We characterized differences in the gut microbiome of school-age healthy children, in association with socioeconomic disparities and household crowding. Stool samples were analyzed from 176 Israeli Arab children aged six to nine years from three villages of different socioeconomic status (SES).
View Article and Find Full Text PDFEnviron Microbiol
January 2022
Locust plagues are a notorious, ancient phenomenon. These swarming pests tend to aggregate and perform long migrations, decimating cultivated fields along their path. When population density is low, however, the locusts will express a cryptic, solitary, non-aggregating phenotype that is not considered a pest.
View Article and Find Full Text PDFBackground: Primary prevention trials have demonstrated that the traditional Mediterranean diet is associated with a reduction in cardiovascular mortality and morbidity. However, this benefit has not been proven for secondary prevention after an acute coronary syndrome (ACS). We hypothesized that a high-intensity Mediterranean diet intervention after an ACS decreases the vulnerability of atherosclerotic plaques by complex interactions between anti-inflammatory effects, microbiota changes and modulation of gene expression.
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