title: Crystallization and preliminary X-ray diffraction studies on the N-utilizing substance A (NusA) from Mycobacterium tuberculosis.
abstract: N-utilizing substance A (NusA) is a protein which performs several roles as a cofactor of DNA-dependent RNA polymerase. Its acts as an elongation factor and facilitates pausing, termination and the formation of a complex assembly that mediates transcription antitermination in eubacteria. Biochemical and biophysical data in the literature suggest that this protein performs these functions by binding to the core RNA polymerase, other protein factors and certain RNA fragments having specific signal sequences. The NusA of Mycobacterium tuberculosis has been cloned and overexpressed in Escherichia coli and crystallized using the hanging-drop vapour-diffusion method. The space group is P3(1)21, with unit-cell parameters a = b = 78.1, c = 180.3 A. A native data set complete to 1.7 A resolution has been collected from a single crystal.
authors.affiliation: Division of Protein Structure, The National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, England.
authors.forename: B
authors.initials: B
authors.lastname: Gopal
authors.forename: K G
authors.initials: KG
authors.lastname: Papavinasasundaram
authors.forename: M J
authors.initials: MJ
authors.lastname: Colston
authors.forename: G
authors.initials: G
authors.lastname: Dodson
authors.forename: L F
authors.initials: LF
authors.lastname: Haire
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification; D003001:Cloning, Molecular; D003460:Crystallization; D018360:Crystallography, X-Ray; D029968:Escherichia coli Proteins; D009169:Mycobacterium tuberculosis / Q000737:chemistry*; D010445:Peptide Elongation Factors; D011487:Protein Conformation; D014157:Transcription Factors / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification; D035602:Transcriptional Elongation Factors
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D010445:Peptide Elongation Factors; D014157:Transcription Factors; D035602:Transcriptional Elongation Factors; C068727:nusA protein, E coli