Streltsov, Victor A.Luang, SukanyaPeisley, AlysVarghese, Joseph N.Ketudat Cairns, James R.Fort, SebastienHijnen, MarcelTvaroška, IgorArda, AnaJiménez-Barbero, JesúsAlfonso-Prieto, MercedesRovira, CarmeMendoza, FernandaTiessler-Sala, LauraSánchez-Aparicio, José-EmilioRodríguez-Guerra, JaimeM. Lluch, JoséMaréchal, Jean-DidierMasgrau, LauraHrmova, Maria2021-09-152021-09-152019-12Nature Communications Volume 10, Issue 11 December 2019 Article number 22222041-1723http://repositorio.unab.cl/xmlui/handle/ria/20270Indexación: ScopuSubstrates associate and products dissociate from enzyme catalytic sites rapidly, which hampers investigations of their trajectories. The high-resolution structure of the native Hordeum exo-hydrolase HvExoI isolated from seedlings reveals that non-covalently trapped glucose forms a stable enzyme-product complex. Here, we report that the alkyl β-d-glucoside and methyl 6-thio-β-gentiobioside substrate analogues perfused in crystalline HvExoI bind across the catalytic site after they displace glucose, while methyl 2-thio-β-sophoroside attaches nearby. Structural analyses and multi-scale molecular modelling of nanoscale reactant movements in HvExoI reveal that upon productive binding of incoming substrates, the glucose product modifies its binding patterns and evokes the formation of a transient lateral cavity, which serves as a conduit for glucose departure to allow for the next catalytic round. This path enables substrate-product assisted processive catalysis through multiple hydrolytic events without HvExoI losing contact with oligo- or polymeric substrates. We anticipate that such enzyme plasticity could be prevalent among exo-hydrolases. © 2019, Crown.enBiocatalysisCatalytic DomainCrystallography, X-RayEnzyme AssaysGlucosidasesGlycosidesHordeumModels, MolecularMolecular Dynamics SimulationNuclear Magnetic Resonance, BiomolecularPlant ProteinsRecombinant ProteinsSeedlingsSubstrate SpecificityArtículoAtribución 4.0 Internacional (CC BY 4.0)10.1038/s41467-019-09691-z