Autor: |
Dubovskii PV; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences , 16/10 Miklukho-Maklaya str., Moscow 117997, Russia., Dubinnyi MA; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences , 16/10 Miklukho-Maklaya str., Moscow 117997, Russia., Konshina AG; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences , 16/10 Miklukho-Maklaya str., Moscow 117997, Russia., Kazakova ED; Moscow Technological University , 86 Vernadsky pr., Moscow 119571, Russia., Sorokoumova GM; Moscow Technological University , 86 Vernadsky pr., Moscow 119571, Russia., Ilyasova TM; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences , 16/10 Miklukho-Maklaya str., Moscow 117997, Russia., Shulepko MA; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences , 16/10 Miklukho-Maklaya str., Moscow 117997, Russia., Chertkova RV; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences , 16/10 Miklukho-Maklaya str., Moscow 117997, Russia., Lyukmanova EN; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences , 16/10 Miklukho-Maklaya str., Moscow 117997, Russia.; Biological Faculty, Lomonosov Moscow State University , 119234 Moscow, Russia., Dolgikh DA; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences , 16/10 Miklukho-Maklaya str., Moscow 117997, Russia.; Biological Faculty, Lomonosov Moscow State University , 119234 Moscow, Russia., Arseniev AS; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences , 16/10 Miklukho-Maklaya str., Moscow 117997, Russia.; Moscow Institute of Physics and Technology (State University) , 9 Institutskiy per., Dolgoprudny, Moscow Region 141700, Russia., Efremov RG; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences , 16/10 Miklukho-Maklaya str., Moscow 117997, Russia.; Higher School of Economics , 20 Myasnitskaya, Moscow 101000, Russia.; Moscow Institute of Physics and Technology (State University) , 9 Institutskiy per., Dolgoprudny, Moscow Region 141700, Russia. |
Abstrakt: |
Today, recombinant proteins are quite widely used in biomedical and biotechnological applications. At the same time, the question about their full equivalence to the native analogues remains unanswered. To gain additional insight into this problem, intimate atomistic details of a relatively simple protein, small and structurally rigid recombinant cardiotoxin I (CTI) from cobra Naja oxiana venom, were characterized using nuclear magnetic resonance (NMR) spectroscopy and atomistic molecular dynamics (MD) simulations in water. Compared to the natural protein, it contains an additional Met residue at the N-terminus. In this work, the NMR-derived spatial structure of uniformly 13 C- and 15 N-labeled CTI and its dynamic behavior were investigated and subjected to comparative analysis with the corresponding data for the native toxin. The differences were found in dihedral angles of only a single residue, adjacent to the N-terminal methionine. Microsecond-long MD traces of the toxins reveal an increased flexibility in the residues spatially close to the N-Met. As the detected structural and dynamic changes of the two CTI models do not result in substantial differences in their cytotoxicities, we assume that the recombinant protein can be used for many purposes as a reasonable surrogate of the native one. In addition, we discuss general features of the spatial organization of cytotoxins, implied by the results of the current combined NMR and MD study. |