3FRL

The 2.25 A crystal structure of LipL32, the major surface antigen of Leptospira interrogans serovar Copenhageni

Summary for 3FRL

• Entry DOI: 10.2210/pdb3frl/pdb
• Descriptor: LipL32, 2,2',2''-NITRILOTRIETHANOL, OXALATE ION, ... (5 entities in total)
• Functional Keywords: core jelly-roll fold, membrane protein
• Biological source: Leptospira interrogans serovar Copenhageni
• Total number of polymer chains: 2
• Total formula weight: 55998.32

Authors

Farah, C.S.,Guzzo, C.R.,Hauk, P.,Ho, P.L. (deposition date: 2009-01-08, release date: 2009-06-16, Last modification date: 2024-10-09)

Primary citation

Hauk, P.,Guzzo, C.R.,Roman Ramos, H.,Ho, P.L.,Farah, C.S.
Structure and calcium-binding activity of LipL32, the major surface antigen of pathogenic Leptospira sp.
J.Mol.Biol., 390:722-736, 2009

PubMed Abstract: Leptospirosis, a spirochaetal zoonotic disease caused by Leptospira, has been recognized as an important emerging infectious disease. LipL32 is the major exposed outer membrane protein found exclusively in pathogenic leptospires, where it accounts for up to 75% of the total outer membrane proteins. It is highly immunogenic, and recent studies have implicated LipL32 as an extracellular matrix binding protein, interacting with collagens, fibronectin, and laminin. In order to better understand the biological role and the structural requirements for the function of this important lipoprotein, we have determined the 2.25-A-resolution structure of recombinant LipL32 protein corresponding to residues 21-272 of the wild-type protein (LipL32(21-272)). The LipL32(21-272) monomer is made of a jelly-roll fold core from which several peripheral secondary structures protrude. LipL32(21-272) is structurally similar to several other jelly-roll proteins, some of which bind calcium ions and extracellular matrix proteins. Indeed, spectroscopic data (circular dichroism, intrinsic tryptophan fluorescence, and extrinsic 1-amino-2-naphthol-4-sulfonic acid fluorescence) confirmed the calcium-binding properties of LipL32(21-272). Ca(2+) binding resulted in a significant increase in the thermal stability of the protein, and binding was specific for Ca(2+) as no structural or stability perturbations were observed for Mg(2+), Zn(2+), or Cu(2+). Careful examination of the crystallographic structure suggests the locations of putative regions that could mediate Ca(2+) binding as well as binding to other interacting host proteins, such as collagens, fibronectin, and laminin.

PubMed: 19477185
DOI: 10.1016/j.jmb.2009.05.034

Experimental method

X-RAY DIFFRACTION (2.25 Å)