title: Deciphering the Structural Requirements of Nucleoside Bisubstrate Analogues for Inhibition of MbtA in Mycobacterium tuberculosis: A FB-QSAR Study and Combinatorial Library Generation for Identifying Potential Hits.
abstract: The re-emergence of tuberculosis infections, which are resistant to conventional drug therapy, has steadily risen in the last decade. Inhibitors of aryl acid adenylating enzyme known as MbtA, involved in siderophore biosynthesis in Mycobacterium tuberculosis, are being explored as potential antitubercular agents. The ability to identify fragments that interact with a biological target is a key step in fragment based drug design (FBDD). To expand the boundaries of quantitative structure activity relationship (QSAR) paradigm, we have proposed a Fragment Based QSAR methodology, referred here in as FB-QSAR, for deciphering the structural requirements of a series of nucleoside bisubstrate analogs for inhibition of MbtA, a key enzyme involved in siderophore biosynthetic pathway. For the development of FB-QSAR models, statistical techniques such as stepwise multiple linear regression (SMLR), genetic function approximation (GFA) and GFAspline were used. The predictive ability of the generated models was validated using different statistical metrics, and similarity-based coverage estimation was carried out to define applicability boundaries. To aid the creation of novel antituberculosis compounds, a bioisosteric database was enumerated using the combichem approach endorsed mining in a lead-like chemical space. The generated library was screened using an integrated in-silico approach and potential hits identified.
authors.affiliation: Structural Biology and Bioinformatics Division, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India phone: +91-33-2473-3491 ext.254/236; fax: +91-33-2473-0284/5197.
authors.forename: Lakshmi
authors.initials: L
authors.lastname: Maganti
authors.affiliation: Structural Biology and Bioinformatics Division, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India phone: +91-33-2473-3491 ext.254/236; fax: +91-33-2473-0284/5197.|Current address: Bengal School of Technology & Management, Sugandha, Delhi Road, Hooghly 712102, India.
authors.forename: Sanjit Kumar
authors.initials: SK
authors.lastname: Das
authors.affiliation: Structural Biology and Bioinformatics Division, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India phone: +91-33-2473-3491 ext.254/236; fax: +91-33-2473-0284/5197.|Current address: Computational Biochemistry Group, Institute for Theoretical Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569, Stuttgart, Germany.
authors.forename: Nahren Manuel
authors.initials: NM
authors.lastname: Mascarenhas
authors.affiliation: Structural Biology and Bioinformatics Division, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India phone: +91-33-2473-3491 ext.254/236; fax: +91-33-2473-0284/5197. nghoshal@iicb.res.in.
authors.forename: Nanda
authors.initials: N
authors.lastname: Ghoshal
keywords: Combinatorial library; FB-QSAR; Siderophore; Tuberculosis