Fig. 1: Cryo-EM structure of the HKU5 S protein.
From: Molecular insights into species-specific ACE2 recognition of coronavirus HKU5
a Cryo-EM map shown in side view (Left) at a contour level of 4 σ and the atomic model shown in top view (Middle) of the HKU5 S protein, with protomers displayed in marine blue, purple, and forest green, respectively. Enlarged views of the boxed regions in the middle panel, showing the bound fatty acids (Right), with cryo-EM map shown at a contour level of 3 σ for palmitic acid (orange) and 4 σ for oleic acid (yellow), respectively. b, c Liquid chromatography-mass spectrometry (LC-MS) analysis of purified HKU5 S protein. Top: Chromatograms of C18 and C16 fatty acids. Bottom: Corresponding electrospray ionization time-of-flight (ESI-TOF) mass spectra, with molecular weights of C18H32O2 and C16H34O2 labeled. Intens. intensity, m/z mass/charge ratio. d, e Binding pockets of oleic acid (d) and palmitic acid (e) within the HKU5 S protein, highlighting key residues involved in polar interactions, with hydrophobic residues in pocket 1 (F393, L419, L422, L423, F426, V428, F431, P438, L441, L449, V451, V488, A490, F569, and V571) and pocket 2 (P402, P403, I404, A455, and P502). All residues are shown as sticks.
