Project description:Carbapenem-resistant Acinetobacter baumannii (CRAB) is a critical nosocomial pathogen with limited treatment options. Although antibiotic resistance in CRAB is well-characterized, its interactions with host immunity and the contribution of outer membrane vesicles (OMVs) to pathogenesis remain poorly understood. We examined a clinical CRAB isolate and compared it with the reference strain A19606. Antimicrobial susceptibility testing revealed complete resistance of CRAB to commonly used antibiotics in clinical practice, while A19606 remained susceptible to most agents. In murine intranasal infection models and bone marrow-derived macrophages, CRAB induced significantly stronger activation of inflammatory signaling pathways and elevated levels of pro-inflammatory cytokines relative to A19606. Transcriptomic analysis of infected lung tissue identified differentially expressed genes, enriched for inflammatory response pathways. proteomics showed upregulated proteins in CRAB related to secretion systems. OMVs characterization revealed that CRAB-derived OMVs highly enriched in proteins associated with periplasmic and outer membrane spaces, and more potent in triggering macrophage inflammatory signaling. CRAB displays expansive antibiotic resistance and enhanced pro-inflammatory potential mediated in part by unique OMVs properties. Targeting OMVs formation or host immune modulation may represent effective strategies for combating CRAB infections.
Project description:Venomous animals have traditionally been studied from a proteomic (but also transcriptomic) perspective, often overlooking the study of venom from a genomic point of view until recently. The rise of genomics has led to an increase in the number of reference genomes for non-model organisms, including venomous taxa, enabling new questions on venom evolution from a genomic context. Although venomous snakes are the fundamental model system in venom research, the number of high-quality reference genomes in the group remains limited. In this study, we present a high-quality chromosome-level reference genome for the Arabian horned viper (Cerastes gasperettii), a highly venomous snake native to the Arabian Peninsula. Our highly-contiguous genome allowed us to explore macrochromosomal rearrangements within the Viperidae family, as well as across squamate reptile evolution. Furthermore, we identified a total of ten different toxins conforming the venom’s core, in line with our proteomic results. We also compared microsyntenic changes in the main toxin gene clusters with those of other venomous snake species, highlighting the pivotal role of gene duplication and loss in the emergence and diversification of the two main toxin families for Cerastes gasperettii. Using Illumina data, we reconstructed the demographic history and genome-wide diversity of the species, revealing how historical aridity likely drove population expansions. Finally, this study highlights the importance of using long-read sequencing as well as chromosome-level reference genomes to disentangle the origin and diversification of toxin families in venomous species.
Project description:Venomous animals have traditionally been studied from a proteomic (but also transcriptomic) perspective, often overlooking the study of venom from a genomic point of view until recently. The rise of genomics has led to an increase in the number of reference genomes for non-model organisms, including venomous taxa, enabling new questions on venom evolution from a genomic context. Although venomous snakes are the fundamental model system in venom research, the number of high-quality reference genomes in the group remains limited. In this study, we present a high-quality chromosome-level reference genome for the Arabian horned viper (Cerastes gasperettii), a highly venomous snake native to the Arabian Peninsula. Our highly-contiguous genome allowed us to explore macrochromosomal rearrangements within the Viperidae family, as well as across squamate reptile evolution. Furthermore, we identified a total of ten different toxins conforming the venom’s core, in line with our proteomic results. We also compared microsyntenic changes in the main toxin gene clusters with those of other venomous snake species, highlighting the pivotal role of gene duplication and loss in the emergence and diversification of the two main toxin families for Cerastes gasperettii. Using Illumina data, we reconstructed the demographic history and genome-wide diversity of the species, revealing how historical aridity likely drove population expansions. Finally, this study highlights the importance of using long-read sequencing as well as chromosome-level reference genomes to disentangle the origin and diversification of toxin families in venomous species.
2025-02-18 | PXD060783 | Pride
Project description:Reference genome sequencing for Dungeness crab (Cancer magister)