3BKR

Crystal Structure of Sterol Carrier Protein-2 like-3 (SCP2-L3) from Aedes Aegypti

Summary for 3BKR

• Entry DOI: 10.2210/pdb3bkr/pdb
• Related: 1PZ4 2QZT 3BDQ 3BKS
• Descriptor: Sterol Carrier Protein-2 like-3, PALMITIC ACID (3 entities in total)
• Functional Keywords: sterol carrier, mosquito, fatty acid, palmitic acid, cholesterol, lipid binding protein
• Biological source: Aedes aegypti (Yellowfever mosquito)
• Total number of polymer chains: 1
• Total formula weight: 14437.56

Authors

Dyer, D.H.,Lan, Q.,Forest, K.T. (deposition date: 2007-12-07, release date: 2008-12-09, Last modification date: 2023-08-30)

Primary citation

Dyer, D.H.,Vyazunova, I.,Lorch, J.M.,Forest, K.T.,Lan, Q.
Characterization of the yellow fever mosquito sterol carrier protein-2 like 3 gene and ligand-bound protein structure.
Mol.Cell.Biochem., 326:67-77, 2009

PubMed Abstract: The sterol carrier protein-2 like 3 gene (AeSCP-2L3), a new member of the SCP-2 protein family, is identified from the yellow fever mosquito, Aedes aegypti. The predicted molecular weight of AeSCP-2L3 is 13.4 kDa with a calculated pI of 4.98. AeSCP-2L3 transcription occurs in the larval feeding stages and the mRNA levels decrease in pupae and adults. The highest levels of AeSCP-2L3 gene expression are found in the body wall, and possibly originated in the fat body. This is the first report of a mosquito SCP-2-like protein with prominent expression in tissue other than the midgut. The X-ray protein crystal structure of AeSCP-2L3 reveals a bound C16 fatty acid whose acyl tail penetrates deeply into a hydrophobic cavity. Interestingly, the ligand-binding cavity is slightly larger than previously described for AeSCP-2 (Dyer et al. J Biol Chem 278:39085-39091, 2003) and AeSCP-2L2 (Dyer et al. J Lipid Res M700460-JLR200, 2007). There are also an additional 10 amino acids in SCP-2L3 that are not present in other characterized mosquito SCP-2s forming an extended loop between beta 3 and beta 4. Otherwise, the protein backbone is exceedingly similar to other SCP-2 and SCP-2-like proteins. In contrast to this observed high structural homology of members in the mosquito SCP2 family, the amino acid sequence identity between the members is less than 30%. The results from structural analysis imply that there have been evolutionary constraints that favor the SCP-2 C(alpha) backbone fold while the specificity of ligand binding can be altered.

PubMed: 19130179
DOI: 10.1007/s11010-008-0007-z

Experimental method

X-RAY DIFFRACTION (1.4 Å)