4W4T

The crystal structure of the terminal R domain from the myxalamid PKS-NRPS biosynthetic pathway

Summary for 4W4T

• Entry DOI: 10.2210/pdb4w4t/pdb
• Related: 4U7W
• Descriptor: MxaA, ACETATE ION (3 entities in total)
• Functional Keywords: reductase, thioesterase, rossmann fold, polyketide, non-ribosomal peptide, polyketide synthase, non-ribosomal peptide synthetase, short-chain dehydrogenases, oxidoreductase
• Biological source: Stigmatella aurantiaca
• Total number of polymer chains: 2
• Total formula weight: 93246.92

Authors

Tsai, S.C.,Keasling, J.D.,Luo, R.,Barajas, J.F.,Phelan, R.M.,Schaub, A.J.,Kliewer, J. (deposition date: 2014-08-15, release date: 2015-08-12, Last modification date: 2024-11-06)

Primary citation

Barajas, J.F.,Phelan, R.M.,Schaub, A.J.,Kliewer, J.T.,Kelly, P.J.,Jackson, D.R.,Luo, R.,Keasling, J.D.,Tsai, S.C.
Comprehensive Structural and Biochemical Analysis of the Terminal Myxalamid Reductase Domain for the Engineered Production of Primary Alcohols.
Chem.Biol., 22:1018-1029, 2015

PubMed Abstract: The terminal reductase (R) domain from the non-ribosomal peptide synthetase (NRPS) module MxaA in Stigmatella aurantiaca Sga15 catalyzes a non-processive four-electron reduction to produce the myxalamide family of secondary metabolites. Despite widespread use in nature, a lack of structural and mechanistic information concerning reductive release from polyketide synthase (PKS) and NRPS assembly lines principally limits our ability to redesign R domains with altered or improved activity. Here we report crystal structures for MxaA R, both in the absence and, for the first time, in the presence of the NADPH cofactor. Molecular dynamics simulations were employed to provide a deeper understanding of this domain and further identify residues critical for structural integrity, substrate binding, and catalysis. Aggregate computational and structural findings provided a basis for mechanistic investigations and, in the process, delivered a rationally altered variant with improved activity toward highly reduced substrates.

PubMed: 26235055
DOI: 10.1016/j.chembiol.2015.06.022

Experimental method

X-RAY DIFFRACTION (1.845 Å)