title: Selenomethionine labeling of large biological macromolecular complexes: probing the structure of marine bacterial virus PM2.
abstract: There is a need for improved tools for labeling protein species within large macromolecular assemblies. Here we describe a method for the efficient selenomethionine labeling of the membrane-containing bacterial virus PM2 for structural studies. By examining potential host cells a strain was found which was auxotrophic for methionine, and by performing a multiparameter search of conditions it was possible to derive a robust protocol which simultaneously minimized the toxic effects of the selenomethionine, so that a reasonable virus yield was maintained, whilst still achieving essentially complete labeling. This has allowed us to fingerprint the protein constituents of the virus in a relatively low resolution electron density map. Such a technique can be adapted to other macromolecule complexes studied by X-ray crystallography.
authors: Department of Biological and Environmental Science and Nanoscience Centre, University of Jyväskylä, P.O. Box 35 (Survontie 9), 40014 Jyväskylä, Finland.
authors: Hanna M
authors: HM
authors: Kivelä
authors: Nicola G A
authors: NG
authors: Abrescia
authors: Jaana K H
authors: JK
authors: Bamford
authors: Jonathan M
authors: JM
authors: Grimes
authors: David I
authors: DI
authors: Stuart
authors: Dennis H
authors: DH
authors: Bamford
mesh_terms: D019240:Corticoviridae / Q000737:chemistry* / Q000648:ultrastructure*; D018360:Crystallography, X-Ray; D008722:Methods; D012645:Selenomethionine / Q000737:chemistry*
chemical_list: D012645:Selenomethionine