Open AccessCrystallization and X‐ray diffraction analysis of a novel surface‐adhesin protein: protein E from Haemophilus influenzae
Author(s) -
Singh Birendra,
Al Jubair Tamim,
Förnvik Karolina,
Thunnissen Marjolein M.,
Riesbeck Kristian
Publication year - 2012
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309111055503
Subject(s) - bacterial adhesin , vitronectin , haemophilus influenzae , laminin , crystallization , bacterial outer membrane , extracellular matrix , microbiology and biotechnology , basement membrane , chemistry , biophysics , biology , materials science , escherichia coli , biochemistry , gene , fibronectin , organic chemistry , antibiotics
Protein E (PE) is a ubiquitous multifunctional surface protein of Haemophilus spp. and other bacterial pathogens of the Pasteurellaceae family. H. influenzae utilizes PE for attachment to respiratory epithelial cells. In addition, PE interacts directly with plasminogen and the extracellular matrix (ECM) components vitronectin and laminin. Vitronectin is a complement regulator that inhibits the formation of the membrane‐attack complex (MAC). PE‐mediated vitronectin recruitment at the H. influenzae surface thus inhibits MAC and protects against serum bactericidal activity. Laminin is an abundant ECM protein and is present in the basement membrane that helps in adherence of H. influenzae during colonization. Here, the expression, purification and crystallization of and the collection of high‐resolution data for this important H. influenzae adhesin are reported. To solve the phase problem for PE, Met residues were introduced and an SeMet variant was expressed and crystallized. Both native and SeMet‐containing PE gave plate‐like crystals in space group P 2 1 , with unit‐cell parameters a = 44, b = 57, c = 61 Å, β = 96°. Diffraction data collected from native and SeMet‐derivative crystals extended to resolutions of 1.8 and 2.6 Å, respectively.