Fig. 5: Conformational changes between the AdhE compact and extended states.

a Sub-domain motion in the AlDH domain. Ribbon representation of the AlDH domain from AdhE. The NAD-binding domain (residues 1–214) is colored in green. The catalytic domain (residues 215–448) is represented in blue. The NAD-binding domains are represented in the same position for the compact and extended state. The catalytic domain moves relative to the NAD-binding domain between AdhE compact and extended states. The axis of the catalytic domain is represented in red for the compact conformation (C) and yellow for the extended conformation (E). Top, side view of the AlDH domain. Bottom, view from the catalytic domain. b Zoomed view of the AlDH catalytic site of compact and extended AdhE and monofunctional propionaldehyde dehydrogenase from R. palustris. The proteins are represented as blue ribbons. The catalytic histidine, glutamate and cysteine are represented as sticks and volumes. They are colored in yellow. The NAD⁺ molecules are represented as sticks. c Surface representation of the AdhE filament in its extended (left) and compact (right) conformation. The ADH domains are colored in beige and the AlDH domains are colored in pink. The NAD⁺ molecules are colored in green.