Differences between CusA and AcrB crystallisation highlighted by protein flexibility

Until very recently, AcrB was the only Resistance Nodulation and cell Division transporter for which the structure has been elucidated. Towards a general understanding of this protein family, CusA and AcrB were compared. In dodecylmaltoside, AcrB crystallised in many different conditions, while CusA does not. This could be due to the difference in dynamic between these proteins as judged from limited proteolysis assays. Addition of various compounds, in particular heavy metal cations, stabilises CusA. This approach could constitute a first step towards CusA crystallisation.