title: Evaluation of stereo-array isotope labeling (SAIL) patterns for automated structural analysis of proteins with CYANA.
abstract: Recently we have developed the stereo-array isotope labeling (SAIL) technique to overcome the conventional molecular size limitation in NMR protein structure determination by employing complete stereo- and regiospecific patterns of stable isotopes. SAIL sharpens signals and simplifies spectra without the loss of requisite structural information, thus making large classes of proteins newly accessible to detailed solution structure determination. The automated structure calculation program CYANA can efficiently analyze SAIL-NOESY spectra and calculate structures without manual analysis. Nevertheless, the original SAIL method might not be capable of determining the structures of proteins larger than 50 kDa or membrane proteins, for which the spectra are characterized by many broadened and overlapped peaks. Here we have carried out simulations of new SAIL patterns optimized for minimal relaxation and overlap, to evaluate the combined use of SAIL and CYANA for solving the structures of larger proteins and membrane proteins. The modified approach reduces the number of peaks to nearly half of that observed with uniform labeling, while still yielding well-defined structures and is expected to enable NMR structure determinations of these challenging systems.
authors.affiliation: Japan Biological Informatics Consortium (JBIC), Japan.
authors.forename: Teppei
authors.initials: T
authors.lastname: Ikeya
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Terauchi
authors.forename: Peter
authors.initials: P
authors.lastname: Güntert
authors.forename: Masatsune
authors.initials: M
authors.lastname: Kainosho
mesh_terms: D000581:Amidohydrolases / Q000737:chemistry; D000596:Amino Acids / Q000737:chemistry; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry; D002147:Calmodulin / Q000737:chemistry; D007553:Isotope Labeling / Q000379:methods*; D007554:Isotopes / Q000032:analysis; D008432:Mathematical Computing; D019906:Nuclear Magnetic Resonance, Biomolecular; D011487:Protein Conformation; D012984:Software
chemical_list: D000596:Amino Acids; D001425:Bacterial Outer Membrane Proteins; D002147:Calmodulin; D007554:Isotopes; C078167:OMPA outer membrane proteins; D000581:Amidohydrolases; C097307:UDP-3-O-acyl-N-acetylglucosamine deacetylase