Project description:To understand what molecular mechanisms determine the unique interspecies interactions between two predominant oral commensals Streptococcus sanguinis and Corynebacterium durum in the healthy oral cavity. We further investigated the regulatory connection between lipid metabolism and chain elongation based on the global gene expression profiling of the dual species cultures, as well as characterized S. sanguinis glycerol kinase (glpK) as a key gene involved in the interspecies interactions.
Project description:Bacterial interspecies interactions shape the function and structural dynamics of microbial communities and affect disease progression of polymicrobial infections. Here, we present data suggesting that the FemA-FemR-FemI (Fem) cell surface signaling system in P. aeruginosa serves as an interspecies signaling pathway between P. aeruginosa and Mycobacterium species. The Fem system is regulated by the type three secretion system (T3SS) regulator ExsA. Fem system significantly influenced virulence factors in P. aeruginosa, including the quorum sensing systems, pyocyanin production, biofilm formation and the type six secretion systems (T6SSs). Our study using a Galleria mellonella infection model indicates femA deletion significantly increased the host survival rate while femI over-expression decreased it, demonstrating that the Fem system’s role in bacterial pathogenicity in vivo. We propose that the Fem system functions as an interspecies signaling pathway enabling P. aeruginosa to alter its behaviours in response to the presence of mycobacteria.
Project description:we develop an interspecies pluripotent stem cell (PSC) co-culture strategy and uncover a previously unknown mode of cell competition. Interspecies PSC competition occurs during primed but not naive pluripotency, and between evolutionarily distant species. We identified genes related to NF-κB signaling pathways, among others, were upregulated in loser cells and genetic inactivation of RELA, a core component of canonical NF-κB pathway, could overcome interspecies PSC competition. We further showed that an upstream regulator of the NF-κB signaling, MYD88 innate immune signal transduction adaptor, was also involved in promoting loser PSC elimination. Suppressing interspecies PSC competition via genetic perturbation of MYD88 or P65 improved engraftment of human cells in early post-implantation mouse embryos. Our study discovers a new paradigm of cell competition and paves the way for studying evolutionarily conserved cell competition mechanisms during early mammalian development. Strategies developed here to overcome interspecies PSC competition may facilitate interspecies organogenesis between evolutionary distant species, including humans.
Project description:In present, interspecies cloning and interspecies-pregnancy were studied for endangered species rescue. However, the low implantation and survival ratio, spontaneous abortion, and unknown reason embryos absorption are the common and difficult problems of interspecies-pregnancy. In order to discover the mechanism of interspecies-pregnant failure and find ways to overcome the xeon-pregnant obstacles, we chosen the rat embryos pregnant in mouse uterus as a interspecies-pregnancy model. Three groups were set, mouse embryos to mouse recipients (MM) as control group, rat embryos to mouse recipients (RM), and rat and mouse embryos to mouse recipients together (RMM) as experiment groups. The former studies showed that rat embryos live no longer than day 7 of mouse pregnancy (D7). Our results showed that rat embryos survived to D7, and still existed to day 9 of mouse pregnancy (D9) in RM group. Surprisingly, the rat embryos survived to day 13 of the mouse gestation (D13) in RMM group. Microarray analysis was used to detect the global-gene expression profile changes of the whole implantation sites among the three groups at D7 and D9. By this way, we screened out the genes promoting the implanted rat embryos development in a mouse uterus which helped the rat embryos survive to D13 in RMM group compared with RM group, and the genes hindering the rat embryos development in a mouse uterus which prevented rat embryos living longer than D7 in RM group and D13 in RMM group compared with MM group. These findings provide insights into the mechanism of interspecies pregnant failure and new idea for interspecies pregnant studies. Experiment Overall Design: microarray was use to screen the genes among the day 7 and day 9 implantation sites of rat embryos implantation sites in a mouse uterus between rat embryos transfer to mouse recipients and rat embryos transfer to mouse recipients with mouse embryos. The mouse day7 and day 9 embryos implantation sites were use as control. Experiment Overall Design: totally 6 samples were analyzed, each samples two replications (one of them had three replications).
Project description:An in-depth characterization of an observed interspecies interaction between two co-isolated bacteria, Xanthomonas retroflexus and Paenibacillus amylolyticus. Using microsensor measurements for mapping the chemical environment, we show how X. retroflexus promoted an alkalization of its local environment through degradation of amino acids and release of ammonia. When the two species were grown in proximity, the modified local environment induced a morphological change and increased growth of P. amylolyticus followed by sporulation. 2D spatial metabolomics enabled visualization and mapping of the degradation of oligopeptide structures by X. retroflexus and morphological changes of P. amylolyticus through e.g. the release of membrane-associated metabolites. Proteome analysis and microscopy were used to validate the shift from vegetative growth towards sporulation. In summary, we demonstrate how environmental profiling by combined application of microsensor, microscopy, metabolomics and proteomics approaches can reveal growth and sporulation promoting effects resulting from interspecies interactions.
Project description:An in-depth characterization of an observed interspecies interaction between two co-isolated bacteria, Xanthomonas retroflexus and Paenibacillus amylolyticus. Using microsensor measurements for mapping the chemical environment, we show how X. retroflexus promoted an alkalization of its local environment through degradation of amino acids and release of ammonia. When the two species were grown in proximity, the modified local environment induced a morphological change and increased growth of P. amylolyticus followed by sporulation. 2D spatial metabolomics enabled visualization and mapping of the degradation of oligopeptide structures by X. retroflexus and morphological changes of P. amylolyticus through e.g. the release of membrane-associated metabolites. Proteome analysis and microscopy were used to validate the shift from vegetative growth towards sporulation. In summary, we demonstrate how environmental profiling by combined application of microsensor, microscopy, metabolomics and proteomics approaches can reveal growth and sporulation promoting effects resulting from interspecies interactions.
Project description:Application of genome-scale 'omics approaches to dissect subcellular pathways and regulatory networks governing interspecies interactions is dependent, at least initially, on the availability of model systems with well-annotated genomes and tractable genetics. We employed controlled cultivation and next-generation sequencing technology to identify transcriptional responses of euryhaline unicellular cyanobacterium Synechococcus sp. PCC 7002 and a marine facultative aerobe Shewanella putrefaciens W3-18-1 to investigate the effect of C sources and C flux directions on the interactions between these organisms.