Crystal structure and substrate-binding mode of a novel pectate lyase from alkaliphilic Bacillus sp. N16-5

► We solve structures of Bsp165PelA in apo-form and in complex with trigalacturonate. ► Parallel β-helix motif, substrate binding cleft and catalytic residues are conserved. ► Some of the conserved Ca2+ binding residues or secondary structures are altered. ► Novel direct interactions between Bsp165PelA and TGA form without Ca2+ participation.