Inhibition and Biochemical Characterization of Methicillin-Resistant Staphylococcus aureus Shikimate Dehydrogenase: An in Silico and Kinetic Study

Molecules

Claudia Avitia-Domínguez³  Erick Sierra-Campos⁴  José Manuel Salas-Pacheco²  Hugo Nájera¹  Arturo Rojo-Domínguez¹  Jorge Cisneros-Martínez³ 

[1] Departamento de Ciencias Naturales, Universidad Autónoma Metropolitana, Unidad Cuajimalpa. Av. Vasco de Quiroga 4871, Colonia Santa Fe Cuajimalpa, Delegación Cuajimalpa de Morelos, Distrito Federal, C.P. 05300, Mexico;Instituto de Investigación Científica, Universidad Juárez del Estado de Durango, Av. Universidad S/N., Durango, Durango, C.P. 34000, Mexico;Facultad de Medicina y Nutrición, Universidad Juárez del Estado de Durango, Av. Universidad y Fanny Anitúa S/N, Durango, Durango, C.P. 34000, Mexico;Facultad de Ciencias Químicas, Universidad Juárez del Estado de Durango, Av. Artículo 123 S/N Fracc. Filadelfia, Gómez Palacio, Durango, CP. 35010, Mexico

关键词: MRSA;    shikimate dehydrogenase;    homology modeling;    virtual screening;    flexible docking;    enzyme kinetics;   

DOI  :  10.3390/molecules19044491

来源: mdpi

【 摘 要 】

Methicillin-resistant Staphylococcus auerus (MRSA) strains are having a major impact worldwide, and due to their resistance to all β-lactams, an urgent need for new drugs is emerging. In this regard, the shikimate pathway is considered to be one of the metabolic features of bacteria and is absent in humans. Therefore enzymes involved in this route, such as shikimate dehydrogenase (SDH), are considered excellent targets for discovery of novel antibacterial drugs. In this study, the SDH from MRSA (SaSDH) was characterized. The results showed that the enzyme is a monomer with a molecular weight of 29 kDa, an optimum temperature of 65 °C, and a maximal pH range of 9–11 for its activity. Kinetic studies revealed that SDH showed Michaelis-Menten kinetics toward both substrates (shikimate and NADP⁺). Initial velocity analysis suggested that SaSDH catalysis followed a sequential random mechanism. Additionally, a tridimensional model of SaSDH was obtained by homology modeling and validated. Through virtual screening three inhibitors of SaSDH were found (compounds 238, 766 and 894) and their inhibition constants and mechanism were obtained. Flexible docking studies revealed that these molecules make interactions with catalytic residues. The data of this study could serve as starting point in the search of new chemotherapeutic agents against MRSA.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.