Search bioRxiv⌕ Search

bioRxiv · 10.1101/2025.11.02.686173

Tracking the opening of spike crowns on the surface of coronaviruses

Abstract

Circulating over years after the pandemic, SARS-CoV-2 still poses a threat to the human society. The onset of viral infection requires the opening of a trimeric protein, called spike, located on the viral surface essential for binding the host-cell receptors and the subsequent fusion into the host cells. Upon spike-crown opening, one to three Receptor Binding Domains (RBD) rise from the compactly assembled spike head, reaching for the host receptors. Many spike structures were solved that captured RBDs in the different down-to-up trimeric states. These structures not only depict spikes conformational change but also help design the more efficacious antiviral therapeutics. However, such a dynamic crown-opening pathway is hardly described by only few stationary pictures, and questions yet remain. Do all RBDs rise following the same track in the various studies? If they do, what does this track look like? Is there a common adaptive conformational change of spike as its crown opens? Do all trimeric RBDs rise cooperatively in each spike? And how does it relate to the antibody-binding event? Here, a general RBD-rising pathway, describing the crown-opening dynamics using two angular parameters, was proposed based on analyzing the published spike structures. These analyses describe not only the orientational change of individual RBDs, but also the asymmetric rising preference of the trimeric RBDs in a single-spike entity. In addition, the quantified map clearly describes RBDs spatial change upon antibody binding, which is often accompanied by an enlarged crown-opening scale. These findings may provide additional clues to develop therapeutics targeting viral spikes in the future. HighlightsO_LI778 spike structures were analyzed that revealed a general RBD-rising pathway. C_LIO_LIMore intermediate-state RBD structures were identified, one of which might be related to the high FRET-signal state. C_LIO_LIRBD twisted upon rotating up. C_LIO_LIAntibodies elicited larger RBD-rising scales. C_LI In summary and {beta} rotation-parameters were introduced that outlined a general RBD-rising pathway, along which the DOWN-, intermediate-, and UP-state RBDs were easily detected and compared that helped explain unresolved issues and provided additional clues in developing therapeutics targeting viral spikes. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=188 SRC="FIGDIR/small/686173v1_ufig1.gif" ALT="Figure 1"> View larger version (64K): org.highwire.dtl.DTLVardef@10a0be9org.highwire.dtl.DTLVardef@941aa3org.highwire.dtl.DTLVardef@160eeb6org.highwire.dtl.DTLVardef@d81356_HPS_FORMAT_FIGEXP M_FIG C_FIG

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Wu, D.. 2025-11-03. Tracking the opening of spike crowns on the surface of coronaviruses. https://doi.org/10.1101/2025.11.02.686173

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

KEEP EXPLORING

Related preprints

A population-scale landscape of the subgingival microbiome reveals divergent routes to periodontal dysbiosis

Periodontitis is an archetypical mucosal inflammatory disease in which microbiome dysbiosis at the tooth-epithelial interface interacts with host genetic and behavioral risk factors to drive immune-mediated tissue destruction. Although subgingival microbiome compositional shifts are thought to parallel disease severity, microbiome variation at the population-level and its relationship to periodontal clinical phenotypes and disease-modifying factors remain poorly defined. Here, we use unsupervised manifold learning to map the compositional landscape of the subgingival microbiome in 1,355 adults spanning periodontal health to severe periodontitis. We identified eight latent microbiome states organized along a branching continuum from eubiosis to dysbiosis. An intermediate microbial configuration marked ecological destabilization and bifurcation into two distinct periodontitis-associated dysbiotic trajectories, distinguished by links to gingival inflammation and smoking. Although the microbiome trajectories broadly tracked periodontal destruction, a minority of individuals showed discordant microbiome-clinical phenotypes, with some individuals with periodontitis retaining otherwise eubiotic microbiomes enriched for low-abundance pathobionts, while some cases of health or mild disease had highly dysbiotic communities, suggesting distinct host susceptibility. Together, these findings define a population-scale ecological landscape of the subgingival microbiome, reveal divergent trajectories to periodontal dysbiosis, and highlight heterogeneity in the relationship between microbial community structure and clinical disease expression.

microbiology↗

Beta-lactam enhancement against methicillin-resistant Staphylococcus aureus by cell wall blockade is autolysis-dependent: a butyrolactone derivative as case in point

Methicillin-resistant Staphylococcus aureus (MRSA) is non-susceptible to beta-lactams. Blockade of cell wall biosynthesis is a potential target for beta-lactam enhancement but requires further investigation. A butyrolactone derivative enhanced beta-lactams against MRSA strains by reducing the availability of D-Ala-D-Ala. Unlike D-cycloserine, it did not inhibit D-Ala-D-Ala ligase (Ddl). Nor did it show an additive or synergistic effect when combined with cycloserine, indicating a unique mechanism for blocking cell wall precursor production that does not involve the traditional Lipid II pathway. Notably, beta-lactam potentiation by our chemical or D-cycloserine was highly dependent on the intrinsic autolytic ability of the tested MRSA strains. Strains that resisted lysis upon Triton X-100 exposure showed a minimal increase in beta-lactam susceptibility, whereas highly autolytic strains showed significant changes in their beta-lactam MICs. We have thus identified autolytic ability as the Achilles Heel in the strategy of targeting cell wall biosynthesis for beta-lactam potentiation.

microbiology↗

Rapid and largely reversible shifts in the canine fecal metabolome during dietary change

Diet can rapidly change the fecal metabolome, but less is known about recovery after the original diet is restored. We used untargeted UPLC-MS metabolomics to analyze 72 fecal samples from nine Pumi dogs during an owner-managed switch from dry food to raw food and back to dry food. Diet phase accounted for a large proportion of variation in both ionization modes. More than 13,000 LC-MS features changed at the first sampling point after the switch to raw food, with a similarly large response after return to dry food. Among features significant in both comparisons, more than 99% changed in opposite directions. At the final sampling point, no positive-mode (ESI+) features and only 13 negative-mode (ESI-) features differed from the second dry-food baseline under the same threshold. BARF-associated patterns persisted in analyses excluding individual dogs and in pedigree-adjusted candidate models, although individual feature effects depended on normalization. Putative metabolites from several biochemical classes differed in their response and recovery. The fecal metabolome therefore changed rapidly and returned largely toward baseline, with differences among dogs.

microbiology↗