enzyme 2  (Sino Biological)

Journal: bioRxiv

Article Title: Deep mutational scanning of recent SARS-CoV-2 variants highlights changing amino acid preferences within epistatic hotspot residues

doi: 10.64898/2026.03.11.711006

Figure Lengend Snippet: ( A ) Diagram of the RBD substitutions that distinguish Omicron BA.2.86 from Wuhan-Hu-1 (top), Omicron KP.3.1.1 from BA.2.86 (middle), and Omicron LP.8.1 from BA.2.86 (bottom). Dashed lines show propagation of BA.2.86 changes to KP.3.1.1 and LP.8.1, and italicized mutation in LP.8.1 (H445R) indicates a secondary substitution at a site that previously changed from Wuhan-Hu-1 to BA.2.86. Wuhan-Hu-1 reference spike numbering is used throughout the manuscript. ( B-D ) Quality control of the KP.3.1.1 and LP.8.1 RBD site-saturation mutagenesis library as assessed by PacBio sequencing, illustrating the distribution of number of amino acid mutations per barcoded variant (B), the average number of mutations of each type across library variants (C), and the distribution of mutations across sites in the RBD over all variants (D). ( E, F ) Representative FACS gates used to sort RBD + singlet cells for ACE2 binding (E) and singlet cells for RBD expression (F), which is followed by high-throughput sequencing of cells sorted into each bin. ( G, H ) Correlation in per-mutant deep mutational scanning measurements between independently barcoded replicate libraries for ACE2-binding affinity (G) and RBD expression (H) experiments. Red dash indicates the 1:1 line.

Article Snippet: Induced cells were washed with PBS-BSA (BSA 0.2 mg/L), split into 16-OD*mL aliquots, and incubated with biotinylated monomeric human ACE2 protein (ACROBiosystems AC2-H82E8) across a concentration range from 10 -6 to 10 -13 M at 1-log intervals, plus a 0 M sample.

Techniques: Mutagenesis, Control, PacBio Sequencing, Variant Assay, Binding Assay, Expressing, Next-Generation Sequencing

Journal: bioRxiv

Article Title: Deep mutational scanning of recent SARS-CoV-2 variants highlights changing amino acid preferences within epistatic hotspot residues

doi: 10.64898/2026.03.11.711006

Figure Lengend Snippet: ( A ) Heatmap illustrating the impacts of all mutations in the KP.3.1.1 and LP.8.1 RBD on ACE2-binding affinity as determined from FACS-seq experiments with yeast-displayed RBD mutant libraries. ACE2 contact residues (black squares, bottom) defined as RBD residues with non-hydrogen atoms <5Å from ACE2 in the BA.2.86 RBD structure (PDB 8QSQ ). Raw data available in Supplemental Data 1. ( B ) Deep mutational scanning data from (A) mapped to the ACE2-bound BA.2.86 RBD structure (PDB 8QSQ ), illustrating the average effect of mutations at a site (left), and the maximal effect of any mutation at a site (right). Sites of interest are labeled. ACE2 (key motifs only) is shown as transparent gray cartoon. ( C ) Heatmap illustrating the impacts of all mutations in the KP.3.1.1 and LP.8.1 RBD on yeast-surface expression levels, a proxy for folding and expression efficiency. Raw data available in Supplemental Data 1. An interactive version of these heatmaps alongside previously assayed SARS-CoV-2 variant RBDs is available at https://tstarrlab.github.io/SARS-CoV-2-RBD_DMS_Omicron-KP3-LP8/RBD-heatmaps/ .

Article Snippet: Induced cells were washed with PBS-BSA (BSA 0.2 mg/L), split into 16-OD*mL aliquots, and incubated with biotinylated monomeric human ACE2 protein (ACROBiosystems AC2-H82E8) across a concentration range from 10 -6 to 10 -13 M at 1-log intervals, plus a 0 M sample.

Techniques: Binding Assay, Mutagenesis, Labeling, Expressing, Variant Assay

Journal: bioRxiv

Article Title: Deep mutational scanning of recent SARS-CoV-2 variants highlights changing amino acid preferences within epistatic hotspot residues

doi: 10.64898/2026.03.11.711006

Figure Lengend Snippet: ( A ) Correlation between KP.3.1.1 mutant effects on ACE2 binding in the pseudovirus whole-spike DMS study of Dadonaite et al. (change in potency of pseudoviral neutralization via soluble ACE2 protein) versus the yeast-display RBD DMS study presented here (change in binding affinity from FACS-seq titration). Correlations are separated based on residue distance from the ACE2 interface in the ACE2-bound BA.2.86 RBD structure (PDB 8QSQ ). Mutations whose effect on spike-mediated pseudoviral entry was < -2 units per the assay of Dadonaite et al. were not included because it is difficult to reliably measure soluble-ACE2-inhibition of entry when entry is poor. ( B ) Structural context of residues F374 and H505 in the spike trimer (PDB 9ELH ). Center, overall top-down view of the spike trimer with two RBDs in the “down” and one in the “up” conformation. Left, zoom-in on the down-down interface of RBD packing; right, zoom-in on the up-down interface of RBD packing.

Article Snippet: Induced cells were washed with PBS-BSA (BSA 0.2 mg/L), split into 16-OD*mL aliquots, and incubated with biotinylated monomeric human ACE2 protein (ACROBiosystems AC2-H82E8) across a concentration range from 10 -6 to 10 -13 M at 1-log intervals, plus a 0 M sample.

Techniques: Mutagenesis, Binding Assay, Neutralization, Titration, Residue, Inhibition

Journal: bioRxiv

Article Title: Deep mutational scanning of recent SARS-CoV-2 variants highlights changing amino acid preferences within epistatic hotspot residues

doi: 10.64898/2026.03.11.711006

Figure Lengend Snippet: ( A ) Epistatic shift in the effects of mutations on ACE2 binding at each RBD position as measured in the Wuhan-Hu-1 (previously reported in ), KP.3.1.1 or LP.8.1 background compared to those previously measured in Omicron BA.2.86 (previously reported in ). ( B ) Mutation-level plots of epistatic shifts between BA.2.86 and KP.3.1.1 or LP.8.1 at sites of interest. Each scatterplot shows the measured ACE2-binding affinity of each amino acid (plotting character, – indicates deletion character) in the BA.2.86 versus KP.3.1.1 or LP.8.1 backgrounds. Red dashed lines mark the respective wildtype RBD affinities on each axis, and the gray dashed line indicates the additive (non-epistatic) expectation. Interactive plots enabling the comparison of all SARS-CoV-2 variants and scatterplots for all RBD sites are available at https://tstarrlab.github.io/SARS-CoV-2-RBD_DMS_Omicron-KP3-LP8/epistatic-shifts/ .

Article Snippet: Induced cells were washed with PBS-BSA (BSA 0.2 mg/L), split into 16-OD*mL aliquots, and incubated with biotinylated monomeric human ACE2 protein (ACROBiosystems AC2-H82E8) across a concentration range from 10 -6 to 10 -13 M at 1-log intervals, plus a 0 M sample.

Techniques: Binding Assay, Mutagenesis, Comparison