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Miyaoka, R.

Publications and source records attributed to Miyaoka, R..

3 recordsLinked to original sources

Targeted single-cell genomics reveals novel host adaptation strategies of the symbiotic bacteria Endozoicomonas in Acropora tenuis coral

Endozoicomonas bacteria symbiose with various marine organisms and are known to be beneficial for coral health. However, genome analysis of coral-associated Endozoicomonas has been limited owing to the difficulty in cultivation and metagenomic approach by contamination of host-derived sequences. In this study, we applied a novel single-cell genomics technique using droplet microfluidics to obtain single-cell amplified genome (SAGs) for coral-associated Endozoicomonas spp. genome. We obtained seven novel Endozoicomonas genomes from Acropora tenuis coral. These genomes revealed that Endozoicomonas bacteria played host-associated functions in host corals and had undergone independent host-adaptive evolution in different clades. These adaptive evolutions were mediated by host-derived eukaryotic-like genes, some of which were speculated to influence host immune mechanisms. These genes are speculated to enhance coral tolerance to environmental stresses. This study suggests the possibility of host adaptation of Endozoicomonas spp. in symbiosis with corals and their contribution to coral bleaching tolerance.

microbiology↗

Single-cell metabolite detection and genomics reveals uncultivated talented producer

The production of bioactive metabolites is increasingly recognized as an important function of host-associated bacteria. An example is defensive symbiosis that might account for much of the chemical richness of marine invertebrates including sponges (Porifera), one of the oldest metazoans. However, as most complex microbiomes remain largely uncultivated and lack reference genomes, unequivocally linking metabolic functions to a cellular source is a challenge. Here we report an analysis pipeline of microfluidic encapsulation, Raman microscopy, and integrated digital genomics (MERMAID) for an efficient identification of uncultivated producers. We applied this method to the chemically rich bacteriosponge Theonella swinhoei, previously shown to contain Entotheonella symbionts providing most of its bioactive substances except for the antifungal aurantosides that lacked biosynthetic gene candidates in the metagenome. Raman-guided single-bacterial analysis and sequencing revealed a cryptic, distinct multiproducer, Candidatus Poriflexus aureus from a new Chloroflexi lineage. Its exceptionally large genome contains numerous biosynthetic loci and suggested an even higher chemical richness of this sponge than previously appreciated. This study highlights the importance of complementary technologies to uncover microbiome functions, reveals remarkable parallels between distantly related symbionts of the same host, and adds functional support for diverse chemically prolific lineages being present in microbial dark matter. Significance StatementThe production of bioactive metabolites is increasingly recognized as an important function of host-associated bacteria. However, the acquisition of integrated genomic and metabolic data from uncultivated environmental bacteria is still challenging. In this work, we explored the combination of Raman microscopy and single-cell sequencing to localize chemical features to a specific bacterium in an uncultivated microbiome, and we specified the bacteria in the uncultured lineage as a producer of aurantoside, an antifungal natural product, from a chemically and microbially complex sponge. This study offers a new methodology as well as insights into chemical functions of uncultivated life.

microbiology↗

Molecular profiling of lipid droplets inside HuH7 Cells with Raman micro-spectroscopy

Raman imaging has become an attractive technology in molecular biology because of its ability to detect multiple molecular components simultaneously without labeling. Two major limitations in accurately accounting for spectral features, viz. background removal and spectral unmixing, have been overcome by employing a modified and effective routine in multivariate curve resolution (MCR). With our improved strategy, we have spectrally isolated seven structurally specific biomolecules without any post-acquisition spectral treatments. Consequently, the isolated intensity profiles reflected concentrations of corresponding biomolecules with high statistical accuracy. Our study reveals the changes in the molecular composition of lipid droplets (LD) inside HuH7 cells and its relation to the physiological state of the cell. Further, we show that the accurate separation of spectral components permits analysis of in vivo structural modification of molecules after cellular uptake. A detailed discussion is presented to highlight the potential of Raman spectroscopy with MCR in semi-quantitative molecular profiling of living cells.

bioengineering↗