Search bioRxiv⌕ Search

bioRxiv · 10.1101/2020.10.20.340307

Nanotube mediated cell-to-cell communication and cannibalism in Halobacillus sp. GSS1 isolated from Sundarbans, India: A cryptic story of survival under nutrient-limiting condition

Abstract

Microorganisms play a self-protective role by evolving their genetic and metabolic machinery to thrive in extreme environmental habitats. Halophiles are such salt-loving extremophilic microorganisms able to adapt, survive, and tend to grow at high salt concentrations. In this study, we have isolated Halobacillus sp. GSS1 from Sundarbans mangrove, India having a strong salt-tolerant ability (up to 4M) in Zobell Marine 2216 medium. The salt adaptation mechanism of Halobacillus sp. was investigated by Confocal microscopy using [Na+] specific dye, Sodium Green indicating the salt-in strategy for their osmoadaptation. Electron microscopic studies revealed that a contact-dependent cell-to-cell communication was profound among the Halobacillus sp. under nutrient limiting condition. This communication is mediated by nanotube, which is highly recommended for the exchange of molecular information between the two individual bacteria. The existence of the ymdB gene strongly supports our claim for nanotube formation by Halobacillus sp. GSS1. Surprisingly, Halobacillus sp. not only utilizing the nanotubes for communication, rather they desperately use nanotubes as a survival weapon under nutrient limiting conditions by triggering cannibalism. This is the first-ever report on the existence of nanotube mediated cell-to-cell communication and cannibalism in any halophilic bacteria, isolated from Sundarbans mangrove forest, India. HighlightsO_LIThe existence of nanotube mediated cell-to-cell communication was discovered in Halobacillus sp. GSS1, isolated from Sundarbans mangrove, India. C_LIO_LIThe communication of Halobacillus sp. GSS1 was established through single or multiple nanotubes with the neighboring cells. C_LIO_LIIntercellular nanotube communication was possible only after the participation of two individual bacteria. C_LIO_LIHalobacillus sp. GSS1 also uses these nanotubes as a survival weapon by triggering the cannibalism to kill their genetically identical siblings. C_LIO_LIThe presence of the ymdB gene in Halobacillus sp. GSS1 strongly confers the evidence of nanotube formation. C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=191 SRC="FIGDIR/small/340307v1_ufig1.gif" ALT="Figure 1"> View larger version (44K): org.highwire.dtl.DTLVardef@1491155org.highwire.dtl.DTLVardef@1123b5org.highwire.dtl.DTLVardef@13f6509org.highwire.dtl.DTLVardef@10261b2_HPS_FORMAT_FIGEXP M_FIG C_FIG

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Guria, M. K., Sengupta, S., Bhattacharyya, M., Karmakar, P.. 2020-10-20. Nanotube mediated cell-to-cell communication and cannibalism in Halobacillus sp. GSS1 isolated from Sundarbans, India: A cryptic story of survival under nutrient-limiting condition. https://doi.org/10.1101/2020.10.20.340307

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Polyphyletic origins and lineage-specific expansion of chemosensory systems in phylum Actinomycetota

Phylum Actinomycetota (syn. Actinobacteriota or Actinobacteria), one of the largest well-studied bacterial phyla, is renowned for complex morphology, non-motility, ecological versatility, and secondary metabolite production. Chemosensory systems (CSS) are among the most sophisticated prokaryotic signal transduction architectures, yet their evolutionary distribution in this phylum remains poorly understood. Here, a comparative genomic analysis of 693 high-quality genomes spanning the phylum resolves the diversity, distribution, and evolutionary trajectories of CSS. Despite extensive genomic complexity and ecological versatility, only 6.9% of genomes encode complete CSS clusters, confined to a subset of lineages within a few classes, indicating lineage-specific retention or loss. In contrast, two-component systems (TCS) are ubiquitously abundant, with hybrid kinases enriched in CSS-deficient classes, suggesting functional compensation for the absence of dedicated chemosensory pathways. Basal lineages retain simplified CSS (F1 or F5), whereas Actinomycetes show lineage-specific expansion into multiple classes (F5, F8, F9, and ACF), often co-occurring, indicative of enhanced sensory complexity. The phylogeny of CheA homologs shows a polyphyletic distribution, supporting a mosaic evolutionary history shaped by multiple independent acquisitions, diversification, and gene loss. Collectively, our findings show that, unlike motile bacteria, members of Actinomycetota rely predominantly on TCS-driven regulatory networks, with CSS retained only in select lineages where ecological demands require enhanced environmental sensing. This work provides a phylum-wide evolutionary framework for the emergence, diversification, and functional specialization of CSS in non-motile bacteria.

microbiology↗

Integrating Microbial Ecology and Sustainability: Linking Agricultural Waste Gas Streams to Microbial Community Shifts in a Photobioreactor

Photobioreactors (PBRs) coupled to animal housing offer potential for mitigating gaseous emissions such as CO2 and NH3 while simultaneously producing biomass. Here, we present a time-resolved characterization of microbial community dynamics, with a focus on the genetic potential for carbon and nitrogen metabolism. Using a cone-shaped, helical PBR cultivating Arthrospira platensis (Spirulina) and supplied with exhaust air from a chicken house, we characterized microbial communities over continuous exhaust-air exposure and periodic biomass harvesting. Microbiome and gene-centric profiling revealed temporal variation in community composition and in the representation of genes associated with carbon and nitrogen metabolism. Cycle-based dissolved inorganic nitrogen balances showed that the decrease in dissolved inorganic nitrogen was only partially recovered in harvested biomass, while ammonia-oxidizing microorganisms were associated with structured, low-light niches. These observations indicate ammonia-oxidizing potential but do not establish a quantitatively relevant nitrification flux. Structured carrier matrices provided attached-growth niches harboring microbial populations underrepresented in the circulating suspension, while pre-colonized carriers facilitated biomass development during re-inoculation. Overall, our results show that coupling PBRs to agricultural exhaust streams can support biomass production while sustaining spatially structured microbial communities with taxonomic and functional potential. These findings may inform their further development for emission mitigation and circular biomass production.

microbiology↗

Engineered DNA materials shape microbial physiology and ecological selection

Extracellular DNA (eDNA) is both a structural component of microbial biofilms and a potential reservoir of genetic information, yet its role as an ecological material remains largely unexplored. Here we establish engineered extracellular materials as determinants of microbial physiology and community assembly across increasing biological complexity. A three-dimensional DNA hydrogel altered bacterial stress-associated responses, elicited species-dependent phenotypes and transcriptional changes in a defined consortium, and shaped community succession in wastewater-derived microbiomes. Distinct responses to surface-bound oligonucleotides reveal that DNA presentation matters beyond its mere presence. Strikingly, metagenomic sequencing identified rare, hydrogel-specific candidate junctions linking material-derived DNA to microbial genomic sequences, suggesting a previously unexplored interface between extracellular DNA materials and microbial genetic information. These findings reveal a dual role for engineered DNA: its material organization shapes microbial physiology and ecological selection, while its encoded sequences may engage with microbial genomic processes.

microbiology↗