title: Crystallization and preliminary X-ray diffraction studies of sortase A from Streptococcus pneumoniae.
abstract: Sortases are cell-membrane-anchored cysteine transpeptidases that are essential for the assembly and anchoring of cell-surface adhesins in Gram-positive bacteria. Thus, they play critical roles in virulence, infection and colonization by pathogens. Sortases have been classified into four types based on their primary sequence and the target-protein motifs that they recognize. All Gram-positive bacteria express a class A housekeeping sortase (SrtA). Sortase A from Streptococcus pneumoniae (NP_358691) has been crystallized in two crystal forms. Diamond-shaped crystals of ΔN(59)SrtA diffracted to 4.0 Å resolution and belonged to a tetragonal system with unit-cell parameters a = b = 122.8, c = 86.5 Å, α = β = γ = 90°, while rod-shaped crystals of ΔN(81)SrtA diffracted to 2.91 Å resolution and belonged to the monoclinic space group P2(1) with unit-cell parameters a = 66.8, b = 103.47, c = 74.79 Å, α = γ = 90, β = 115.65°. The Matthews coefficient (V(M) = 2.77 Å(3) Da(-1)) with ~56% solvent content suggested the presence of four molecules in the asymmetric unit for ΔN(81)SrtA. Also, a multi-copy search using a monomer as a probe in the molecular-replacement method resulted in the successful location of four sortase molecules in the asymmetric unit, with statistics R = 41.61, R(free) = 46.44, correlation coefficient (CC) = 64.31, CC(free) = 57.67.
authors.affiliation: Department of Physics, Indian Institute of Science, Bangalore 560 012, India.
authors.forename: Anurag
authors.initials: A
authors.lastname: Misra
authors.forename: Tora
authors.initials: T
authors.lastname: Biswas
authors.forename: Sreetama
authors.initials: S
authors.lastname: Das
authors.forename: Uttara
authors.initials: U
authors.lastname: Marathe
authors.forename: Devinder
authors.initials: D
authors.lastname: Sehgal
authors.forename: Rajendra P
authors.initials: RP
authors.lastname: Roy
authors.forename: Ramakumar
authors.initials: R
authors.lastname: Suryanarayanarao
mesh_terms: D019881:Aminoacyltransferases / Q000737:chemistry*; D001426:Bacterial Proteins / Q000737:chemistry*; D018360:Crystallography, X-Ray; D003546:Cysteine Endopeptidases / Q000737:chemistry*; D013296:Streptococcus pneumoniae / Q000201:enzymology*
chemical_list: D001426:Bacterial Proteins; D019881:Aminoacyltransferases; C120542:sortase A; D003546:Cysteine Endopeptidases
references.citation: J Biol Chem. 2009 Mar 13;284(11):6924-33
references.pmid: 19129180
references.citation: Biotechnol Lett. 2010 Jan;32(1):1-10
references.pmid: 19728105
references.citation: Proc Natl Acad Sci U S A. 2001 May 22;98(11):6056-61
references.pmid: 11371637
references.citation: Science. 1999 Jul 30;285(5428):760-3
references.pmid: 10427003
references.citation: J Biol Chem. 2004 Jul 23;279(30):31383-9
references.pmid: 15117963
references.citation: J Am Chem Soc. 2008 Feb 20;130(7):2132-3
references.pmid: 18229923
references.citation: Biochemistry. 2007 Aug 14;46(32):9346-54
references.pmid: 17658894
references.citation: Biopolymers. 2010;94(4):385-96
references.pmid: 20593474
references.citation: Proc Natl Acad Sci U S A. 2000 May 9;97(10):5013-5
references.pmid: 10805759
references.citation: Nat Rev Microbiol. 2011 Mar;9(3):166-76
references.pmid: 21326273
references.citation: Acta Crystallogr D Biol Crystallogr. 2009 Jan;65(Pt 1):1-10
references.pmid: 19153460
references.citation: Acta Crystallogr D Biol Crystallogr. 2004 Mar;60(Pt 3):432-8
references.pmid: 14993666
references.citation: EMBO J. 1993 Dec;12(12):4803-11
references.pmid: 8223489
references.citation: J Mol Biol. 1968 Apr 28;33(2):491-7
references.pmid: 5700707
references.citation: Acta Crystallogr D Biol Crystallogr. 2001 Oct;57(Pt 10):1373-82
references.pmid: 11567148
references.citation: Acta Crystallogr D Biol Crystallogr. 2006 Jan;62(Pt 1):48-57
references.pmid: 16369093