Structure of the monotopic membrane protein (S)-mandelate dehydrogenase at 2.2 Å resolution.

Structure of the monotopic membrane protein (S)-mandelate dehydrogenase at 2.2Å resolution. Biochimie. 2018 Jul 30;: Authors: Sukumar N, Liu S, Li W, Mathews FS, Mitra B, Kandavelu P Abstract The x-ray structure of the monotopic membrane protein (S)-mandelate dehydrogenase (MDH) from Pseudomonas putida reveals an inherent flexibility of its membrane binding segment that might be important for its biological activity. The surface of MDH exhibits a concentration of the positive charges on one side and the negative charges on the other side. The putative membrane binding surface of MDH has a concentric circular ridge, formed by positively charged residues, which projects away from the protein surface by ∼4Å; this is unique structural feature and not observed in other monotopic membrane proteins to our knowledge. There are three α-helixes in the membrane binding region. Based on the structure of MDH, it is possible to propose that the interaction of MDH with the membrane is stabilized by coplanar electrostatic interactions, between the positively charged concentric circular ridge and the negatively charged head-groups of the phospholipid bilayer, along with three α-helixes that provide additional stability by inserting into the membrane. The structure reveals the possible orientation of these helixes along with possible role for the individual residues which form those helixes. These α-helixes may play a role in the enzyme's mobil...
Source: Biochimie - Category: Biochemistry Authors: Tags: Biochimie Source Type: research