Search bioRxiv⌕ Search

bioRxiv · 10.1101/812727

Characterisation of Quorum Sensing System and Its Role in Global Regulation in Hafnia alvei

Abstract

Quorum sensing (QS) is a regulatory process achieved via cell-to-cell communication that involves release and detection of autoinducers (AIs), and which occurs in a wide range of bacteria. To date, QS has been associated to events of pathogenesis, biofilm formation, and antibiotic resistance in clinical, industrial, and agricultural contexts. The main objective of this study was to characterise the role of N-Acyl homoserine lactone (AHL) type QS in Hafnia alvei FB1, a bacterial strain isolated from frozen vacuum-packed fish paste meatballs, via identification of QS core genes using a genomic approach, followed by comparative transcriptomic profiling between QS-deficient mutants and wild-type strains. H. alvei FB1 is known to produce two types of AHLs, namely, N-(3-oxohexanoyl) homoserine lactone (3OC6-HSL) and N-(3-oxooctanoyl) homoserine lactone (3OC8-HSL). The complete genome sequence of strain FB1 was obtained and a single gene for AHL synthase (halI) and its cognate receptor (halR) were identified. QS-deficient mutants of FB1 were constructed via the {lambda}-Red recombineering method. Removal of the QS genes in strain FB1 affected mainly mechanisms in cell division and nutrient uptake, as well as resistance to a number of antibiotics, which are crucial for survival, adaptation and colonisation of both food and the host gut environment. Impact statementThe Hafnia genus is known as opportunistic pathogen in both nosocomial and community-acquired infections, however, involvement and mechanism of pathogenesis of Hafnia in infection diseases is uncertain. We investigate the role of the signalling molecule, N-acyl homoserine lactones (AHLs), in a Hafnia alvei strain, since AHLs play important roles in pathogenicity, survival or adaptation in other pathogen. This comparative transciptomic study has revealed that AHLs are involved in mechanisms in cell division and nutrient uptake, as well as resistance to a number of antibiotics, which are crucial for survival, adaptation and colonisation of both food and the host gut environment. This finding provides insight and possible strategy to combat this opportunistic pathogen. Data summaryGenome sequence is deposited in NCBI GenBank under accession number CP009706. The transcriptomic data, have been deposited in the Gene Expression Omnibus (GEO) database (https://www.ncbi.nlm.nih.gov/gds) under accession number GSE93000.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Tan, J.-Y., See-Too, W.-S., Convey, P., Chan, K.-G.. 2019-10-21. Characterisation of Quorum Sensing System and Its Role in Global Regulation in Hafnia alvei. https://doi.org/10.1101/812727

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

KEEP EXPLORING

Related preprints

MicroDUET: a dual-headed genomic foundation model for pathogen surveillance

Pathogen genomic surveillance works from raw reads, assembled genomes and alignments, representations that are slow and costly to compare at scale. Compact embeddings from genomic language models offer an alternative, but surveillance requires resolving both evolutionary ancestry (phylogeny) and phenotypic capability (function) - which need not co-vary. Here we present MicroDUET, which adapts a 26.6-million-parameter ProkBERT backbone with two 3.5-million-parameter adapter heads: a phylogeny head trained contrastively on genome windows from the same microbes, and a function head trained to identify genes across taxa. On held-out retrieval benchmarks, the phylogeny head returned the correct species for 80.3% and 66.6% of cellular and viral queries, and the function head the correct gene family for 97.3% and 97.2%, reaching 74.4% accuracy on an independent antimicrobial resistance-class benchmark. Across all three benchmarks MicroDUET outranked 17 other genomic encoders. Without training on lineage, clade or drug-susceptibility tasks, MicroDUET identified Mycobacterium tuberculosis and mpox virus lineages and clades (0.965, 0.975 accuracy), discriminated rifampicin resistance without lineage adjustment (AUROC 0.985), and retrospectively identified an emerging mpox lineage as anomalous (AUROC 0.974). MicroDUET operates 10^3 - 10^4 times faster than single-threaded sequence-based alignments. MicroDUET therefore provides a compact, reusable representation for scalable pathogen surveillance and sequence triage.

genomics↗

A chromosome-level genome assembly of northern dragonhead, Dracocephalum ruyschiana L., 1753

We present a chromosome-level genome assembly for the vascular plant northern dragonhead, Dracocephalum ruyschiana. The assembly comprises two pseudo-haplotypes, hap1 and hap2, of 661 Mb and 681 Mb, with 93.6% and 92.5%, respectively, scaffolded into seven chromosomes each - in line with the known karyotype. Assembly quality was high, with conserved single-copy ortholog completeness scores of 97.9% and 97.8%, combined k-mer completeness of 98.1%, and 38,141 and 38,617 annotated protein-coding genes for hap1 and hap2, respectively. This assembly provides a high-quality genomic resource for future research and conservation of northern dragonhead, as well as the endangered northern dragonhead sap beetle, which depends on the plant for reproduction and whose genome assembly is described in a complementary genome note.

genomics↗

Elucidating Bat SuperImmunity: Insights from the Bent-Wing Bat Genome Assembly and Multi-Omics Analysis

Bats have evolved a range of unique adaptations, including powered flight, echolocation, and exceptional longevity. They have also attracted considerable scientific attention, particularly since the COVID-19 pandemic, due to their association with a broad diversity of viruses and their potential role in zoonotic transmission and emerging infectious diseases. Despite hosting numerous viruses, bats often exhibit limited clinical manifestations of infection, suggesting the evolution of distinctive mechanisms of immune regulation and tolerance. Understanding the molecular basis of these mechanisms has become a major focus of current research, with genome-wide analyses providing important insights into the genetic adaptations underlying bat immunity. Nevertheless, the regulatory complexity of bat genomes, particularly the contribution of non-coding RNAs and post-transcriptional RNA editing, remains comparatively underexplored. Here, we present an integrated multi-omic framework for the common bent-wing bat (Miniopterus schreibersii), combining a contiguous chromosome-scale genome assembly with multi-tissue transcriptomic profiling, long non-coding RNA (lncRNA) identification and synteny analysis, endogenous viral elements (EVE) mapping, and same-individual RNA editomic analyses. This study provides a comprehensive resource for investigating genome organization, transcriptional regulation, evolutionary relationships, and post-transcriptional modifications in this species. In particular, it offers an opportunity to explore the potential contribution of non-coding regulatory elements and RNA editing to the molecular mechanisms underlying viral interactions and immune regulation in bats. Collectively, these resources provide a valuable foundation for advancing our understanding of bat genome evolution and the regulatory mechanisms potentially associated with their distinctive responses to viral infections.

genomics↗