Open AccessCrystallization and preliminary X‐ray diffraction studies of delta‐toxin from Clostridium perfringens
Author(s) -
Huyet Jessica,
Gilbert Maryse,
Popoff Michel R.,
Basak Ajit
Publication year - 2011
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309110054187
Subject(s) - toxin , clostridium perfringens , enterotoxin , microbiology and biotechnology , biology , clostridium , crystallization , bacteria , chemistry , escherichia coli , biochemistry , gene , genetics , organic chemistry
Clostridium perfringens is a Gram‐positive anaerobic bacterium that is responsible for a wide range of diseases in humans and both wild and domesticated animals, including birds. C. perfringens is notable for its ability to produce a plethora of toxins, e.g. phospholipases C (alpha‐toxin), pore‐forming toxins (epsilon‐toxin, beta‐toxin and enterotoxin) and binary toxins (iota‐toxin). Based on alpha‐, beta‐, epsilon‐ and iota‐toxin production, the bacterium is classified into five different toxinotypes (A–E). Delta‐toxin, which is a 32.6 kDa protein with 290 amino acids, is one of three haemolysins released by type C and possibly by type B strains of C. perfringens . This toxin is immunogenic and lytic to erythrocytes from the even‐toed ungulates sheep, goats and pigs, and is cytotoxic to other cell types such as rabbit macrophages, human monocytes and blood platelets from goats, rabbits, guinea pigs and humans. The recombinant delta‐toxin has been cloned, expressed, purified and crystallized in two different crystal forms by the hanging‐drop vapour‐diffusion method. Of these two different crystal forms, only the form II crystal diffracted to atomic resolution ( d min = 2.4 Å), while the form I crystal diffracted to only 15 Å resolution. The form II crystals belonged to space group P 2 1 2 1 2, with one molecule in the crystallographic asymmetric unit and unit‐cell parameters a = 49.66, b = 58.48, c = 112.93 Å.