title: Expression, purification, crystallization and preliminary crystallographic analysis of SpaA, a major pilin from Corynebacterium diphtheriae.
abstract: Bacterial pili are cell-surface organelles that are critically involved in adhesion to host cells, leading to the colonization of host tissues and the establishment of infections. Whereas the pili of Gram-negative bacteria have been extensively studied, those of Gram-positive bacteria came to light only recently after the discovery and characterization of Corynebacterium diphtheriae pili. These newly discovered pili are formed by the covalent polymerization of pilin subunits catalyzed by sortase enzymes, making them fundamentally different from the noncovalent pilin assemblies of Gram-negative bacteria. Here, the expression, crystallization and preliminary crystallographic analysis of SpaA, which forms the shaft of one of the three types of pili expressed by C. diphtheriae, are reported. SpaA(53-486) crystals diffracted to 1.6 A resolution and belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 34.9, b = 64.1, c = 198.7 A, alpha = beta = gamma = 90 degrees .
authors: School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand.
authors: Hae Joo
authors: HJ
authors: Kang
authors: Neil G
authors: NG
authors: Paterson
authors: Edward N
authors: EN
authors: Baker
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D001483:Base Sequence; D003001:Cloning, Molecular; D003353:Corynebacterium diphtheriae / Q000737:chemistry*; D003460:Crystallization; D018360:Crystallography, X-Ray; D017931:DNA Primers; D036781:Fimbriae Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D001426:Bacterial Proteins; D017931:DNA Primers; D036781:Fimbriae Proteins