 Your new post is loading...
|
Scooped by
mhryu@live.com
Today, 12:48 PM
|
Computational bacteriophage host prediction from genomic sequences remains challenging because host range depends on diverse, rapidly evolving genomic determinants—from receptor-binding proteins to anti-defense systems and downstream infection compatibility—and because the signals available to predictors, including sequence homology, CRISPR spacer matches, nucleotide composition, and mobile genetic elements, are sparse, unevenly distributed across taxa, and constrained by incomplete host annotations. Here, we frame host prediction as an unsupervised retrieval problem. We asked whether embeddings from the pretrained genome language model Evo2 captured a reliable host-range signal without training on phage–host labels. We generated whole-genome embeddings for phages and candidate bacterial hosts with the Evo2-7B model, applied normalization, and ranked hosts by cosine similarity. Using the Virus-Host Database, we selected embedding and fusion choices on a Gram-positive validation cohort and then evaluated the approach on a held-out Gram-negative test cohort to minimize data leakage. We found that Evo2 was strongest at retrieving multiple plausible hosts, with the recorded host in the top 10 for 55.4% of phages. However, it did not maximize species-level top-1 accuracy (19.4% vs. 23.2% for the best baseline). At higher taxonomic ranks, Evo2 captured a coarser host-range signal: top-1 accuracy reached 43.4% at the genus level and 51.6% at the family level. Reciprocal rank fusion of Evo2 with BLASTN, VirHostMatcher, and PHIST improved all retrieval metrics. Top-10 retrieval rose to 58.5% and top-1 accuracy to 26.9%. Stratified analyses by phage genome length, host clade, and host mobile genetic element coverage revealed scenario-dependent performance. Evo2 embeddings excelled for intermediate-length phages and when host mobile element content was low, whereas alignment and k-mer methods dominated when local homology was abundant. These results suggest that pretrained genome embeddings complement established alignment- and k-mer/composition-based methods and that context-aware hybrid pipelines may help improve phage host prediction.
|
Scooped by
mhryu@live.com
Today, 12:34 PM
|
Efficient production of human proteins for the development of tool compounds and biologics depends on a detailed understanding of the protein expression machinery in mammalian cells. Codon optimization is widely believed to enhance protein yield, yet its impact in homologous mammalian systems remains poorly defined. Here, we systematically compare five codon usage strategies reflecting common assumptions about rare codons, RNA stability, and synthesis efficiency. We developed pTipi, an efficient open source mammalian expression vector, and evaluated its performance in antibody production. We generated plasmids for common epitope tag antibodies such as V5, anti-biotin and anti-His for distribution by Addgene. To compare codon usage schemes, we performed a bake-off of 18 human and murine Wnt pathway glycoproteins in mammalian cells. Small-scale expression screens revealed that codon optimization does not provide a general advantage over native coding sequences, while strategies prioritizing RNA stability consistently reduced expression. Interestingly, a skewed codon scheme using the most abundant codons produced yields comparable to native sequences and occasionally enhanced protein output. To enable flexible evaluation of codon strategies, we implemented a Golden Gate compatible pTipi platform for efficient synthetic gene incorporation. We conclude that native codons are sufficient for robust homologous mammalian expression of glycoproteins, while selective codon skewing can be beneficial for some targets.
|
Scooped by
mhryu@live.com
Today, 12:11 PM
|
Nitrogen assimilation relies on photosynthetically produced energy and reducing equivalents. Here, we identify a small protein, PsbO-interacting regulator of nitrate assimilation (PirN), as a key coordinator of photosynthesis and nitrate assimilation in Synechocystis sp. PCC 6803. PirN specifically accumulates in nitrate-grown cells and interacts with the photosystem II (PSII) subunit PsbO. Deletion of pirN (ΔpirN) under nitrate impairs growth, reduces PSII contents and oxygen evolution, and upregulates most nitrogen transport and assimilation proteins except the nitrate reductase NarB, mimicking nitrogen starvation response likely due to impaired nitrate reduction. PsbO expression is markedly reduced in both ΔpirN and ΔnarB mutants. Complementation of narB or psbO in the ΔpirN mutant background largely rescued the growth defect of the mutant and led to increased expression of PsbO or NarB, respectively. These findings suggest that PirN is a nitrate-inducible regulator that hierarchically modulates NarB and PsbO expression to couple nitrate assimilation with photosynthetic activity. This coordination likely safeguards redox homeostasis when nitrate assimilation or photosynthetic electron production is perturbed.
|
Scooped by
mhryu@live.com
Today, 11:57 AM
|
In recent years, CRISPR/Cas gene editing technology has become a fundamental method in biological breeding. As a vital tool for overcoming technological obstacles, it is currently widely used in functional gene research and genetic enhancement across a variety of organisms. Currently, CRISPR activation (CRISPRa) technology based on dCas9 fusion transcription activation domains has emerged as a powerful tool for expanding the application of CRISPR/Cas systems in improving traits in plants, animals, and microorganisms. This overview starts by going over the underlying principles and components of gene activation editing technology, as well as the phases of development of its three generations. It summarises the present difficulties and potential directions in this field while concentrating on the use of gene activation editing in important crop traits including growth and development regulation, stress resistance, and quality regulation. The objective is to offer valuable insights for the research and development of crop breeding.
|
Scooped by
mhryu@live.com
March 20, 1:47 AM
|
Protein–protein interactions (PPIs) are fundamental to cellular function and metabolic regulation. Mapping these complex molecular networks is essential for understanding signaling pathways, yet it remains challenging due to their transient nature. We discuss how next-generation proximity labeling is evolving from bulk methods toward precise, dynamic PPI mapping, providing actionable biological insights.
|
Scooped by
mhryu@live.com
March 20, 1:27 AM
|
Site-specific insertion of gene-sized DNA fragments remains an unmet need in the field of genome editing. IS110-family serine recombinases have recently been shown to mediate programmable DNA recombination in bacteria by using a bispecific RNA guide (bridge RNA) that simultaneously recognizes target and donor sites. In this work, we have shown that the bridge recombinase ISCro4 is highly active in human cells and provided structural insights into its enhanced activity. Using plasmid- or all-RNA–based delivery, ISCro4 supports programmable multikilobase excisions and inversions and facilitates donor DNA insertion at genomic sites with efficiencies that exceed 6%. Last, we assessed ISCro4 specificity and off-target activity. These results establish a framework for the development of bridge recombinases as next-generation tools for editing modalities that are beyond the capabilities of current technologies.
|
Scooped by
mhryu@live.com
March 20, 1:04 AM
|
Training physical neural networks directly in matter remains difficult because most platforms do not implement weight storage and weight update within the same physical substrate. Here we show that engineered E. coli can implement a genetically encoded local learning rule acting on a persistent biological memory. In memregulons, analogue weights are stored as plasmid copy-number ratios in a coupled two-plasmid system and are rewritten by activity-dependent growth bias under a global negative learning signal. In single-strain cultures, theory predicts that the change in mean weight is proportional to the activity of the learning channel and to the standing variance of the stored distribution, and flow-cytometry trajectories across eight distinct promoters driving the learning channel support this prediction quantitatively. At the single-cell level, repeated negative learning also reshapes the stored distribution by narrowing it and increasing its skewness as weights approach the lower boundary. In mixed populations and nine-strain co-cultures, one global negative learning signal selectively rewrites only the active memregulons, enabling supervised adaptation in a bacteria-versus-bacteria tic-tac-toe tournament. We then generalise this principle across nine orthogonal chemical inputs and combinatorial promoters, including channels controlled by quorum-sensing molecules, and use it to rationally design a biological XOR gate. Finally, we examine multilayer ANN-like architectures with a human-in-the-loop protocol in which weight updates remain physically implemented and parameterised by experimental measurements, while inter-layer communication is supplied externally. These results establish a route to physical learning in living matter and provide a modular foundation for adaptive multicellular computation, paving the way for autonomous biological hardware capable of distributed environmental sensing and next-generation cellular therapeutics.
|
Scooped by
mhryu@live.com
March 20, 12:42 AM
|
Protein-function prediction is crucial for elucidating molecular mechanisms driving biological processes and therapeutics development. Despite numerous computational tools demonstrating promising performance, they fall short when predicting rare, uncharacterized functions or indirect activities. Here, we present COSMOS, a context-aware Gene Ontology (GO) subgraph mining system for protein-function prediction. By leveraging inductive subgraph foundation models and an enriched knowledge graph of protein-GO relationships, COSMOS performs zero-shot, few-shot, and low-homology protein-function prediction. Built on 7,923,952 functional semantic relationships, COSMOS demonstrates robust capabilities to (1) generate state-of-the-art predictions for GO classes with sparse or no experimental annotations, (2) provide interpretable functional subgraphs for transparent rationale analysis, and (3) deliver complementary benefits when integrated with existing embedding-based prediction methods. We anticipate that COSMOS will serve as a complementary approach to conventional protein annotation methods and an interpretable tool for predicting protein functions within underexplored GO classes, thereby advancing genomics and therapeutic research.
|
Scooped by
mhryu@live.com
March 20, 12:05 AM
|
The ability to access, search, and analyse large collections of RNA molecules together with their secondary structure and evolutionary context is essential for comparative and phylogeny-driven studies. Although RNA secondary structure is known to be more conserved than primary sequence, no existing resource systematically associates individual RNA molecules with curated phylogenetic classifications. Here, we introduce PhyloRNA, a curated meta-database that provides large-scale access to RNA secondary structures collected from public resources or derived from experimentally resolved 3D structures. PhyloRNA allows users to search, select, and download extensive sets of RNA molecules in multiple textual formats, each entry being explicitly linked to phylogenetic annotations derived from five curated taxonomy systems. In addition to taxonomic information, each RNA molecule is accompanied by a rich set of descriptors, including pseudoknot order, genus, and three levels of structural abstraction - Core, Core Plus, and Shape - which facilitate comparative analyses across sets of molecules. PhyloRNA is publicly available at https://bdslab.unicam.it/phylorna/ and is regularly updated to incorporate newly available data and revised taxonomic annotations.
|
Scooped by
mhryu@live.com
March 19, 11:58 PM
|
RNA is frequently chemically modified, with over 170 types of chemical modifications identified to date in cellular RNAs. These modifications, along with their effector proteins, constitute new layers of gene expression regulation by controlling either the fate of modified RNAs at nearly every stage of their life cycle or local transcription through modulating the nearby chromatin state and transcriptional complexes. This is especially evident in dynamic biological contexts such as cellular state transitions, signaling, immune responses, and stress adaptation. In this review, we discuss recent breakthroughs and promising avenues for future exploration. Particular attention is given to the functional significance of mRNA modifications, the emerging roles of modifications on chromatin-associated regulatory RNAs in chromatin and transcriptional regulation, and mechanistic insights that will guide future scientific interrogation of RNA modifications in gene expression regulation. We also highlight how these fundamental understandings are beginning to catalyze the development of novel therapeutic strategies.
|
Scooped by
mhryu@live.com
March 19, 11:33 PM
|
Polyhydroxyalkanoate (PHA) synthases are a group of complex, dimeric enzymes which catalyze polymerization of R-hydroxyacids into PHAs. PHA properties depend on their monomer composition but enzymes found in nature have limited specificities to certain R-hydroxyacids only. In this study, a conditional variational autoencoder was used for the first time to design novel PHA synthases. The model was trained with native protein sequences obtained from Uniprot and was used for the creation of approximately 10 000 new PHA synthase enzymes. Out of these, 16 sequences were selected for in vivo validation. The selection criteria included the presence of conserved residues such as catalytic amino acids and amino acids in the dimer interface and structural features like the number of -helices in the N-terminal part of the enzyme. Two of the 16 novel PHA synthases that had substantial numbers of amino acid substitutions (87 and 98) with respect to the most similar native enzymes were confirmed active and produced poly(hydroxybutyrate) (PHB) when expressed in yeast S. cerevisiae. The results show the power of AI based methods to create active variants of highly complex dimer enzymes.
|
Scooped by
mhryu@live.com
March 19, 11:07 PM
|
A major challenge in microbiome research is the inherent complexity and inter-individual variability of the human gut microbiota. To address this, we have developed a detailed protocol for establishing and analyzing a Simplified Human Intestinal Microbiota(SIHUMI)—a defined, in vitro bacterial consortium composed of seven fully sequenced and anaerobically culturable human gut commensals. This model enables highly reproducible and controlled experiments, in which the individual growth of each member can be quantitatively tracked over time (up to 48 h) via species-specific qPCR. The protocol outlines optimized and standardized steps, including consortium setup, time-resolved sample collection, DNA extraction and qPCR analysis. It can be used to evaluate community dynamics in response to interventions such as nutrients, antimicrobials or other xenobiotics. The system is readily adaptable: additional strains can be incorporated, including pathogens (e.g., Clostridioides difficile), to transform it into an infectious disease model. In addition, we describe two optional rapid methods for assessing interspecies interactions and provide an open-source web app for generating interaction network plots. This enables exploration of ecological mechanisms and potential off-target effects. The entire workflow—from setup to data acquisition—can be completed within 1 week. This qPCR-based protocol offers a validated and accessible platform for gut microbiome research, providing a standardized, strain-level and time-resolved alternative to 16S- or fluorescence-based workflows and enabling quantitative, scalable analysis of defined microbial communities. This protocol enables users to establish a defined, in vitro consortium composed of seven fully sequenced and anaerobically culturable human gut bacteria and follow the growth of individual members via strain-specific qPCR to evaluate community dynamics in response to interventions.
|
Scooped by
mhryu@live.com
March 19, 10:54 PM
|
The rapidly developing search engines for glycopeptide identification and accumulated high-resolution glycoproteomic data underscore the need for robust downstream data mining platforms towards subsequently functional and mechanistic studies. Here, we introduce StrucGAP, a Structural Glycoproteomics Analysis Platform for scalable downstream data mining of site-specific N-glycoproteomics. It integrates modules for data quality control, overall glycan structural characterization, altered glycan feature extraction, functional annotation, as well as upstream regulation and downstream networks. Its visualization and insight-tracking functionalities distill interpretation across hundreds of outputs, uniquely enabling to generate chart-based analysis reports and extract key glycosylation insights—capabilities rarely found in existing omics tools. Applying StrucGAP to an uncharacterized aging mouse uterus dataset reveals bidirectional regulation of core-fucosylation, and progressive, coordinated enrichment of glycans featuring sialylation via Neu5Ac, Lewis epitopes, and hybrid glycans along glycosylation dynamics. These changes are functionally linked to adhesion and remodeling, demonstrating StrucGAP’s ability to distill critical glycosylation insights from multi-dimensional information of structural N-glycoproteome datasets. StrucGAP is a structural glycoproteomics analysis platform that distills multi-dimensional information of glycoproteome datasets into structural and functional insights towards mechanistic studies.
|
|
Scooped by
mhryu@live.com
Today, 12:41 PM
|
Protein function annotation is fundamental to understanding biological mechanisms, designing therapeutics, and advancing biomedical research. Current computational methods either rely on shallow sequence similarity or treat function prediction as isolated classification tasks, failing to capture the integrative reasoning across sequence, structure, domains, and interactions that expert biologists perform to infer function. We introduce BioReason-Pro, the first multimodal reasoning large language model (LLM) for protein function prediction that integrates protein embeddings with biological context to generate structured reasoning traces. A key input into BioReason-Pro is the set of GO term predictions made by GO-GPT, our autoregressive transformer that captures hierarchical and cross-aspect dependencies of GO terms. BioReason-Pro is trained via supervised fine-tuning on synthetic reasoning traces generated by GPT-5 for over 130K proteins and further optimized through reinforcement learning. It achieves 73.6% Fmax on GO term prediction and an LLM judge score of 8/10 on functional summaries, substantially outperforming previous methods. Evaluations with human protein experts show that BioReason-Pro annotations are preferred over ground truth UniProt annotations in 79% of cases. Remarkably, BioReason-Pro de novo predicted experimentally confirmed binding partners with per-residue attention localizing to the exact contact residues resolved in cryo-EM structures of those complexes. Together, GO-GPT and BioReason-Pro establish a framework for protein function prediction that combines precise ontology modeling with interpretable biological reasoning.
|
Scooped by
mhryu@live.com
Today, 12:25 PM
|
Radiotherapy (RT) remains a cornerstone in cancer treatment, yet its efficacy is often compromised by tumor-acquired radioresistance, driven in part by lactate accumulation in the tumor microenvironment (TME). Lactate fosters therapeutic resistance through aberrant DNA repair, immunosuppression, and metabolic reprogramming, posing a formidable clinical challenge. Here, we report a precision microbial therapy leveraging engineered E. coli Nissle 1917 (EcNΔnlpIIHCL, ENHL) to target and deplete lactate in the TME. By utilizing engineered bacteria with nlpI gene deletion to enhance outer membrane vesicles (OMVs) biogenesis and introducing a bifunctional surface display system (INP-HlpA for tumor targeting and ClyA-EGFP for tracking), ENHL delivers lactate oxidase (LOx) to neutralize acidic stress. In vitro and in vivo studies confirm that ENHL and LOx-loaded OMVs effectively radiosensitize colorectal cancer cells by depleting tumor-derived and radiation-induced lactate. Oral administration of ENHL selectively colonizes tumors, where arabinose induction triggers localized LOx expression, significantly improving radiosensitivity and immune cell infiltration while modulating gut microbiota. This synergistic approach—combining targeted metabolic modulation with microbial precision therapy—represents a transformative strategy to overcome RT resistance in colorectal cancer, offering a promising pathway toward clinical translation.
|
Scooped by
mhryu@live.com
Today, 12:00 PM
|
Plants have evolved sophisticated defense mechanisms to counter pathogen invasion, including the production of antimicrobial compounds, regulation of defense-related protein expression, and the synthesis of defense hormones across various subcellular organelles. While the significant contribution of organelle functions in plant immunity is increasingly recognized, the specific roles of these organelles in the immune response remain poorly understood. Recent studies have revealed that pathogen effectors from diverse microbes such as fungi, oomycetes, and bacteria localize within various organelles. These effectors target host proteins to manipulate the plant immune system, underscoring the crucial role of organelle functions in plant immunity. This review not only focuses on the localization of effectors within subcellular organelles, excluding the nucleus, but also explores the implications of organelle functions in the plant immune response. Gaining a deeper understanding of how these effectors interact with their targets in specific organelles will pave the way for developing disease-resistant plants.
|
Scooped by
mhryu@live.com
Today, 11:52 AM
|
Bioluminescent reporters are widely used to monitor and image biological processes. Among these, NanoLuc luciferase and its complementation variants (LgBiT/SmBiT and LgBiT/HiBiT) are commonly used due to their brightness, sensitivity, and compatibility with prolonged kinetic measurements. However, the single-channel emission of these NanoLuc-based systems (460 nm peak) limits their use in multiplexed assays. Prior efforts to shift NanoLuc’s emission employed bioluminescence resonance energy transfer (BRET) to a proximal fluorescent protein or organic fluorophore. Building on this concept, we engineered high-efficiency BRET reporters, termed NanoPrism luciferases, by inserting circularly permuted NanoLuc or LgBiT into a surface loop of the self-labeling HaloTag protein. These NanoPrisms achieve a ∼90% BRET efficiency by optimally positioning NanoLuc variants near a fluorophore covalently bound to HaloTag. The binary design further supports high- and low-affinity complementation, allowing applications in HiBiT knock-in cells and tracking protein–protein interactions, respectively. Pairing red-shifted NanoPrisms with unmodified NanoLuc or its complementation variants, we created a two-color bioluminescent reporter platform featuring bright signals of similar intensity and >100 nm spectral separation, allowing quantitative, simultaneous measurement of two molecular readouts within the same sample. Here, we demonstrate the platform’s utility for monitoring a degradation target alongside a control protein and for tracking two distinct events within a biological pathway, using plate-based detection and bioluminescence imaging. By enabling concurrent measurements within the same sample, the system provides insights into cellular dynamics while reducing variability and complexity associated with parallel single-channel assays.
|
Scooped by
mhryu@live.com
March 20, 1:36 AM
|
Bacterial outer membrane vesicles (OMVs) and the cargo they carry are increasingly recognized as a means of communication between microbial symbionts and the cells of their host. However, few studies have focused on the biochemical and molecular mechanisms underlying OMV signaling during symbiosis onset and development. We show here that SypC, an OMV protein of the bioluminescent symbiont Vibrio fischeri, is taken up by cells of the squid host Euprymna scolopes where it assumes a new function, i.e., the facilitation of symbiont-induced light-organ morphogenesis. SypC is a Wza-like outer membrane protein found in host-associated Vibrionaceae and is essential for V. fischeri biofilm formation. Colonization or direct treatment with V. fischeri OMVs triggers host development, which was reduced or delayed if the host is instead exposed to a ∆sypC mutant or ∆sypC OMVs. RNA-seq analyses comparing light organs colonized by either the mutant or its parent revealed differential expression of host genes associated with immune responses and tissue morphogenesis. In immunocytochemical imaging, SypC-bearing OMVs were taken up by the host’s macrophage-like cells near the light-organ crypts, revealing the mechanism by which SypC travels through tissue to trigger morphogenesis. Taken together, the data provide evidence that in addition to its role in biofilm formation and colonization, SypC has a second function promoting the induction of symbiotic-tissue development. These findings provide a critical piece of a puzzle whereby a rich array of host and symbiont molecules work in concert to orchestrate normal symbiont colonization and host development within the first hours to days of symbiosis.
|
Scooped by
mhryu@live.com
March 20, 1:23 AM
|
The transfer of virulence factors into eukaryotic cells is a hallmark of bacterial pathogenesis. We report the expression, interspecies transfer, subcellular localization, and potential functions of three unusually large virulence factor-like proteins that underlie a bipartite mutualistic bacterial symbiosis. These proteins are synthesized by green sulfur bacterial epibionts surrounding a central motile chemoheterotroph in the multicellular phototrophic consortium 'Chlorochromatium aggregatum'. While symbiosis-proteins remain intracellular during axenic epibiont growth, they are transferred to the partner bacterium in the association. An RTX-like protein secreted towards the central bacterium is capable of degrading its alginate capsule, thereby promoting direct cell-to-cell contact. Two gigantic hemagglutinin-like proteins are predicted to fold when binding extracellular Ca2+ to form Type 6-like auto injection needles, explaining their observed transfer into the central bacterium. These functionalities extend far beyond the known pathogenic interactions of bacteria with eukaryotes and provide new perspectives on the evolution of bacterial virulence factors.
|
Scooped by
mhryu@live.com
March 20, 12:46 AM
|
Rice paddies naturally host methane-oxidizing bacteria known as methanotrophs, due to the production of methane in flooded soils. Enhancing the activity of native methanotrophs could improve the sustainability of rice cultivation, but knowledge of how this could impact other members of the rice microbiome remains incomplete. To gain insight into which members of the rice microbiome might benefit from increased methanotrophic activity, we passaged 51 aerobic microbial enrichment cultures from rice rhizosphere and tissue samples in a chemically-defined medium with methane as the primary carbon source and electron donor. We profiled the cultures over time by 16S rRNA gene amplicon sequencing and sequenced the genomes of 44 isolates to gain functional insights. Taxa whose relative abundance increased during community growth on methane represented more than a dozen families, many of which are not known to utilize one-carbon substrates. Several of the enriched genera have not previously been linked to methane cycling in rice fields, and genomic analysis of the sequenced isolates revealed considerable variation in predicted carbon source utilization and nitrogen cycling capabilities. Together, these findings broaden the understanding of how aerobic methanotrophs may impact microbiome assembly and nutrient cycling in rice paddies.
|
Scooped by
mhryu@live.com
March 20, 12:09 AM
|
Plastic biodegradation in natural environments is increasingly recognized as a multi-organism process, yet the mechanisms enabling coordinated depolymerization and metabolism of polyethylene terephthalate (PET) remain poorly understood. Previously, we demonstrated that a full consortium containing three Pseudomonas and two Bacillus strains isolated from hydrocarbon-rich coastal soils of Galveston Bay, Texas, can synergistically depolymerize PET plastic and utilize it as a sole carbon source, a capacity not observed in individual isolates. In this report, using integrated comparative genomics, proteomics, and chemical analyses, we show that PET degradation in this system reflects exaptation of hydrocarbon metabolism reinforced by metabolic division of labor. Within this naturally occurring consortium, Bacillus strains persist under environmental stress, establish biofilms, and perform essential secondary hydrolysis, while Pseudomonas strains catabolize aromatic monomers and buffer oxidative stress. Genes supporting these functions are enriched within the accessory genomes of the consortium strains, indicating consortium-enriched horizontal gene transfer (HGT). In addition to the canonical two-step hydrolytic pathway well documented in PET biodegradation, we identify a secondary methylation- and redox-associated process, mechanisms where the full consortium acts on the oligomer mono(2-hydroxyethyl) terephthalate (MHET), yielding nearly complete conversion to terephthalic acid (TPA) and methylated MHET (MMHET). Together, these findings demonstrate how cooperation and competition within consortia facilitate targeted gene exchange, enabling emergent plastic biodegradation in natural microbial communities.
|
Scooped by
mhryu@live.com
March 20, 12:02 AM
|
By mapping ribosome-protected fragments (RPFs) genome-wide, ribosome profiling (Ribo-seq) has uncovered extensive translation beyond conventional coding sequences, revealing non-canonical ORFs (ncORFs) with emerging roles in diverse biological processes. However, protocol-induced biases introduced during library construction can substantially distort RPF signals. Most existing ORF callers are not designed to explicitly account for such artifacts, limiting robust ncORF identification. Here, we present RiboBA, a bias-aware probabilistic framework to address this challenge. RiboBA consists of two main components: a generative module that recovers protocol-induced biases and codon-level ribosome occupancy, and a supervised module that identifies translated ORFs and initiation sites using the resulting bias-adjusted profiles. Evaluated through simulations and on a range of Ribo-seq datasets-particularly supported by cell-type-specific immunopeptidomics-RiboBA robustly recovers protocol-induced parameters and achieves superior accuracy and sensitivity in ncORF identification. Notably, RiboBA performs particularly well on RNase I libraries with attenuated three-nucleotide periodicity, as well as on MNase and nuclease P1 libraries, while maintaining competitive runtimes. In a Drosophila case study, RiboBA identifies conserved ncORFs with coding potential, including recurrent upstream translation of ThrRS and Mettl2 that suggests a potential threonine-specific translational control axis.
|
Scooped by
mhryu@live.com
March 19, 11:44 PM
|
Attaching and effacing pathogens, including enterohemorrhagic E. coli (EHEC), colonize their preferred intestinal niche by sensing diverse host-, diet-, and microbiota-derived signals and coordinating the expression of virulence factors. D-serine, a host metabolite abundant in urine but scarce in the intestine, restricts EHEC colonization by transcriptionally repressing the type 3 secretion system (T3SS) while activating the SOS stress response. However, the mechanism underlying virulence regulation by D-serine remains unestablished. Here, we show that multiple amino acids, including L-serine converge on this pathway, repressing the T3SS without inducing the SOS response. Transcriptomic analyses showed a common response to D- and L-serine dominated by repression of nitrogen stress response genes. Mutational analysis identified the response regulators NtrC and Nac as essential mediators of T3SS repression by both serine enantiomers. Disruption of L-serine deaminase enzymes crucially revealed that T3SS repression depends on cytoplasmic ammonia/ammonium release rather than sensing of intact serine. While EHEC lacks canonical D-serine catabolic capacity, through metabolomics we provide evidence of oxidative deamination activity, capable of producing this regulatory signal. Together, these findings establish a mechanistic link between amino acid catabolism, nitrogen stress signaling, and virulence regulation in EHEC, highlighting how metabolic flux fine-tunes pathogen adaptation to intestinal niches.
|
Scooped by
mhryu@live.com
March 19, 11:25 PM
|
Artificial intelligence (AI) is poised to reshape the research paradigm of the life sciences by rapidly advancing the adoption of protein language models and their derivative tools. These technologies are increasingly being applied to protein structure prediction, function analysis, and protein design throughout the life sciences, and have only recently begun to gain attention within the plant science community. Moreover, while the era of AI-driven bio-breeding is on the horizon, it remains largely in the proof-of-concept stage. Therefore, there is a pressing need not only to outline the fundamental principles, models, and tools in this rapidly evolving field, but also to explore their potential applications in plant research and crop breeding. This review begins by introducing general principles and widely used models for protein understanding and generation, supported by illustrative case studies that highlight how these tools are advancing fundamental plant research. For instance, the analyses of two maize (Zea mays) genes demonstrate how a structure-aware interpretation of the relationships between mutations and protein function enables more precise hypothesis generation and facilitates experimental validation. Subsequently, the review presents generic AI-enabled protein engineering strategies and pipelines, including rational, semi-rational, refactoring, and de novo design, tailored to diverse protein engineering objectives. These approaches aim to create artificial variants and synthetic proteins with improved or novel functions to foster innovation in crop breeding. Finally, the significant challenges of applying protein design in plants are discussed, particularly in light of the limited availability of experimentally resolved protein structures and the inherent complexity of plant biological systems.
|
Scooped by
mhryu@live.com
March 19, 11:00 PM
|
Protein structures provide a wealth of information regarding biological functions and underlying mechanisms. The growing availability of high-quality structure predictions and extended molecular simulations has further expanded the potential to leverage these data in a myriad of different ways. Yet, an abundance of data can obscure important information, making it difficult to focus on biologically relevant features. Residue interaction networks (RINs) address this challenge by condensing structural data into subsets of well-defined noncovalent molecular interactions. In this Protocol, we explore how the RIN generator (RING) software can be used to gain biological insights by constructing detailed RINs for proteins and protein–ligand complexes. We provide a step-by-step guide to performing both single- and multi-state protein analyses using the RING web server and a stand-alone software package. In addition, we include a dedicated procedure for sequential multi-file analysis, which can be performed exclusively through the command-line interface. All potential inputs and outputs are explained in detail, along with strategies for downstream data processing. Designed for researchers in biology and related fields with minimal or no programming experience, the entire workflow can be completed in <45 min. Residue interaction networks (RINs) describe noncovalent molecular interactions within and between proteins. This Protocol uses RING software to generate these networks from protein structures toward understanding protein structure and function.
|