Crystallization and preliminary x-ray crystallographic analysis of the 38-kda immunodominant antigen of mycobacterium tuberculosis

✍ Scribed by Abha Choudhary; Meenakshi N. Vyas; Nand K. Vyas; Zengyi Chang; Florante A. Quiocho

• Publisher: Cold Spring Harbor Laboratory Press
• Year: 1994
• Tongue: English
• Weight: 190 KB
• Volume: 3
• Category: Article
• ISSN: 0961-8368
• DOI: 10.1002/pro.5560031229

✦ Synopsis

Abstract

The 38‐kDa lipoprotein is one of the most potent cell surface immunogens of Mycobacterium tuberculosis in antibody‐and T cell‐mediated reactions. Using a pure recombinant form of the protein, we have recently shown that it binds phosphate much like that of the phosphate‐binding protein (M~r~ = 34.4 kDa) that is localized in the periplasm of Escherichia coli and is involved as an initial receptor for active transport of phosphate. The purified 38‐kDa protein has been crystallized in 2 forms that are suitable for high‐resolution structural analyses. One form belongs to the monoclinic space group P2~1~ with unit cell dimensions of a = 67.42 Å, b = 113.38 Å, c = 42.68 Å, and β = 108.53°. The other is of the orthorhombic space group P2~1~2~1~2 with a = 125.46 Å, b = 72.27 Å, and c = 73.43 Å. Both crystal forms diffract to about 2 Å resolution on a fine focus rotating anode.