{"text": "We have compared genomes of Alteromonas macleodii \"deep ecotype\" isolates from two deep Mediterranean sites and two surface samples from the Aegean and the English Channel. A total of nine different genomes were analyzed. They belong to five clonal frames (CFs) that differ among them by approximately 30,000 single-nucleotide polymorphisms (SNPs) over their core genomes. Two of the CFs contain three strains each with nearly identical genomes (~100 SNPs over the core genome). One of the CFs had representatives that were isolated from samples taken more than 1,000 km away, 2,500 m deeper, and 5 years apart. These data mark the longest proven persistence of a CF in nature (outside of clinical settings). We have found evidence for frequent recombination events between or within CFs and even with the distantly related A. macleodii surface ecotype. The different CFs had different flexible genomic islands. They can be classified into two groups; one type is additive, that is, containing different numbers of gene cassettes, and is very variable in short time periods (they often varied even within a single CF). The other type was more stable and produced the complete replacement of a genomic fragment by another with different genes. Although this type was more conserved within each CF, we found examples of recombination among distantly related CFs including English Channel and Mediterranean isolates.\n\nGenomic diversity of \"deep ecotype\" Alteromonas macleodii isolates: evidence for Pan-Mediterranean clonal frames.", "token_count": 358, "char_count": 1528, "word_count": 235, "semantic_coherence": 1, "information_density": 0.634, "quality_score": 0.817, "entities": {"genes": [], "proteins": [], "pathways": [], "organisms": [], "conditions": ["ph"]}, "biobert_ready": true, "timestamp": "2025-11-01T07:07:19.689273", "source": {"split": "train_shard_00002", "doc_id": 656}, "chunk_id": "train_shard_00002_656_0", "global_id": 13600} {"text": "Noroviruses are associated with one fifth of diarrheal illnesses globally and are not yet preventable with vaccines. Little is known about the effects of norovirus infection on infant gut microbiome health, which has a demonstrated role in protecting hosts from pathogens and a possible role in oral vaccine performance. In this study, we characterized infant gut microbiome changes occurring with norovirus-associated acute gastroenteritis (AGE) and the extent of recovery. Metagenomic sequencing was performed on the stools of five infants participating in a longitudinal birth cohort study conducted in León, Nicaragua. Taxonomic and functional diversities of gut microbiomes were profiled at time points before, during, and after norovirus infection. Initially, the gut microbiomes resembled those of breastfeeding infants, rich in probiotic species. When disturbed by AGE, Gammaproteobacteria dominated, particularly Pseudomonas species. Alpha diversity increased but the genes involved in carbohydrate metabolism and glycan biosynthesis decreased. After the symptoms subsided, the gut microbiomes rebounded with their taxonomic and functional communities resembling those of the pre-infection microbiomes. In this study, during disruptive norovirus-associated AGE, the gut microbiome was temporarily altered, returning to a pre-infection composition a median of 58 days later. Our study provides new insights for developing probiotic treatments and furthering our understanding of the role that episodes of AGE have in shaping the infant gut microbiome, their long-term outcomes, and implications for oral vaccine effectiveness.\n\nGut Microbiome Changes Occurring with Norovirus Infection and Recovery in Infants Enrolled in a Longitudinal Birth Cohort in Leon, Nicaragua.", "token_count": 416, "char_count": 1784, "word_count": 244, "semantic_coherence": 1, "information_density": 0.6148, "quality_score": 0.8074, "entities": {"genes": [], "proteins": [], "pathways": ["metabolism"], "organisms": [], "conditions": ["gut", "ph"]}, "biobert_ready": true, "timestamp": "2025-11-01T07:07:20.315190", "source": {"split": "train_shard_00002", "doc_id": 657}, "chunk_id": "train_shard_00002_657_0", "global_id": 13601} {"text": "Enterohemorrhagic and enteropathogenic Escherichia coli are gastrointestinal pathogens that disrupt the intestinal microvilli to form attaching and effacing (A/E) lesions on infected cells and cause diarrhea. This pathomorphological trait is encoded within the pathogenicity island locus of enterocyte effacement (LEE). The LEE houses a type 3 secretion system (T3SS), which upon assembly bridges the bacterial cytosol to that of the host and enables the bacterium to traffic dozens of effectors into the host where they hijack regulatory and signal transduction pathways and contribute to bacterial colonization and disease. Owing to the importance of the LEE to EHEC and EPEC pathogenesis, much of the research on these pathogens has centered on its regulation. To date, over 40 proteinaceous factors have been identified that control the LEE at various hierarchical levels of gene expression. In contrast, RNA-based regulatory mechanisms that converge on the LEE have only just begun to be unraveled. In this minireview, we highlight major breakthroughs in small RNAs (sRNAs)-dependent regulation of the LEE, with an emphasis on their mechanisms of action and/or LEE-encoded targets.\n\nThe Tip of the Iceberg: On the Roles of Regulatory Small RNAs in the Virulence of Enterohemorrhagic and Enteropathogenic Escherichia coli.", "token_count": 353, "char_count": 1340, "word_count": 196, "semantic_coherence": 1, "information_density": 0.6531, "quality_score": 0.8265, "entities": {"genes": [], "proteins": [], "pathways": [], "organisms": [], "conditions": ["ph"]}, "biobert_ready": true, "timestamp": "2025-11-01T07:07:20.894786", "source": {"split": "train_shard_00002", "doc_id": 658}, "chunk_id": "train_shard_00002_658_0", "global_id": 13602} {"text": "About 2,500 papers dated 2014-2016 were recovered by searching the PubMed database for Streptomyces, which are the richest known source of antibiotics. This review integrates around 100 of these papers in sections dealing with evolution, ecology, pathogenicity, growth and development, stress responses and secondary metabolism, gene expression, and technical advances. Genomic approaches have greatly accelerated progress. For example, it has been definitively shown that interspecies recombination of conserved genes has occurred during evolution, in addition to exchanges of some of the tens of thousands of non-conserved accessory genes. The closeness of the association of Streptomyces with plants, fungi, and insects has become clear and is reflected in the importance of regulators of cellulose and chitin utilisation in overall Streptomyces biology. Interestingly, endogenous cellulose-like glycans are also proving important in hyphal growth and in the clumping that affects industrial fermentations. Nucleotide secondary messengers, including cyclic di-GMP, have been shown to provide key input into developmental processes such as germination and reproductive growth, while late morphological changes during sporulation involve control by phosphorylation. The discovery that nitric oxide is produced endogenously puts a new face on speculative models in which regulatory Wbl proteins (peculiar to actinobacteria) respond to nitric oxide produced in stressful physiological transitions. Some dramatic insights have come from a new model system for Streptomyces developmental biology, Streptomyces venezuelae, including molecular evidence of very close interplay in each of two pairs of regulatory proteins. An extra dimension has been added to the many complexities of the regulation of secondary metabolism by findings of regulatory crosstalk within and between pathways, and even between species, mediated by end products", "token_count": 466, "char_count": 1968, "word_count": 267, "semantic_coherence": 1, "information_density": 0.6854, "quality_score": 0.8427, "entities": {"genes": [], "proteins": [], "pathways": ["metabolism", "fermentation"], "organisms": [], "conditions": ["ph"]}, "biobert_ready": true, "timestamp": "2025-11-01T07:07:21.540851", "source": {"split": "train_shard_00002", "doc_id": 659}, "chunk_id": "train_shard_00002_659_0", "global_id": 13603} {"text": "Among many outcomes from the application of chromosome immunoprecipitation sequencing (ChIP-seq) analysis and other methods based on \"next-generation sequencing\" has been the finding that 21% of Streptomyces mRNA species lack leader sequences and conventional ribosome binding sites. Further technical advances now emerging should lead to continued acceleration of knowledge, and more effective exploitation, of these astonishing and critically important organisms.\n\nRecent advances in understanding Streptomyces.", "token_count": 123, "char_count": 527, "word_count": 65, "semantic_coherence": 1, "information_density": 0.8769, "quality_score": 0.9385, "entities": {"genes": [], "proteins": [], "pathways": [], "organisms": [], "conditions": []}, "biobert_ready": true, "timestamp": "2025-11-01T07:07:21.919650", "source": {"split": "train_shard_00002", "doc_id": 659}, "chunk_id": "train_shard_00002_659_1", "global_id": 13604} {"text": "N-Acyl lipids are important mediators of several biological processes including immune function and stress response. To enhance the detection of N-acyl lipids with untargeted mass spectrometry-based metabolomics, we created a reference spectral library retrieving N-acyl lipid patterns from 2,700 public datasets, identifying 851 N-acyl lipids that were detected 356,542 times. 777 are not documented in lipid structural databases, with 18% of these derived from short-chain fatty acids and found in the digestive tract and other organs. Their levels varied with diet and microbial colonization and in people living with diabetes. We used the library to link microbial N-acyl lipids, including histamine and polyamine conjugates, to HIV status and cognitive impairment. This resource will enhance the annotation of these compounds in future studies to further the understanding of their roles in health and disease and to highlight the value of large-scale untargeted metabolomics data for metabolite discovery.\n\nThe microbiome diversifies long- to short-chain fatty acid-derived N-acyl lipids.", "token_count": 267, "char_count": 1094, "word_count": 156, "semantic_coherence": 1, "information_density": 0.6731, "quality_score": 0.8365, "entities": {"genes": [], "proteins": [], "pathways": [], "organisms": [], "conditions": ["acid"]}, "biobert_ready": true, "timestamp": "2025-11-01T07:07:22.473857", "source": {"split": "train_shard_00002", "doc_id": 660}, "chunk_id": "train_shard_00002_660_0", "global_id": 13605} {"text": "