Parasitology

Research Article

Characterization of hydrophobic-ligand-binding proteins of Taenia solium that are expressed specifically in the adult stage

M. RAHMANa1, E.-G. LEEa1, S.-H. KIMa1, Y.-A. BAEa1, H. WANGa2, Y. YANGa3 and Y. KONGa1 c1

a1 Department of Molecular Parasitology, Sungkyunkwan University School of Medicine and Center for Molecular Medicine, Samsung Biomedical Research Institute, Suwon 446-740, Republic of Korea

a2 Qinghai Province Institute for Endemic Diseases Prevention and Control, Qinghai Centers for Disease Prevention and Control, Xining, China

a3 Parasitology Institute, Guangxi Centers for Disease Prevention and Control, Nanning, China

SUMMARY

Taenia solium, a causative agent of taeniasis and cysticercosis, has evolved a repertoire of lipid uptake mechanisms. Proteome analysis of T. solium excretory-secretory products (TsESP) identified 10 kDa proteins displaying significant sequence identity with cestode hydrophobic-ligand-binding-proteins (HLBPs). Two distinct 362- and 352-bp-long cDNAs encoding 264- and 258-bp-long open reading frames (87 and 85 amino acid polypeptides) were isolated by mining the T. solium expressed sequence tags and a cDNA library screening (TsHLBP1 and TsHLBP2; 94% sequence identity). They clustered into the same clade with those found in Moniezia expansa and Hymenolepis diminuta. Genomic structure analysis revealed that these genes might have originated from a common ancestor. Both the crude TsESP and bacterially expressed recombinant proteins exhibited binding activity toward 1-anilinonaphthalene-8-sulfonic acid (1,8-ANS), which was competitively inhibited by oleic acid. The proteins also bound to cis-parinaric acid (cPnA) and 16-(9-anthroyloxy) palmitic acid (16-AP), but showed no binding activity against 11-[(5-dimethylaminonaphthalene-1-sulfonyl) amino] undecanoic acid (DAUDA) and dansyl-DL-α-aminocaprylic acid (DACA). Unsaturated fatty acids (FAs) showed greater affinity than saturated FAs. The proteins were specifically expressed in adult worms throughout the strobila. The TsHLBPs might be involved in uptake and/or sequestration of hydrophobic molecules provided by their hosts, thus contributing to host-parasite interface interrelationships.

(Received October 19 2011)

(Revised December 12 2011)

(Revised February 14 2012)

(Accepted March 17 2012)

(Online publication June 01 2012)

Correspondence:

c1 Corresponding author: Department of Molecular Parasitology, Sungkyunkwan University School of Medicine, 300 Cheoncheon-dong, Jangan-gu, Suwon 440-746, Korea. Tel: +82 31 299 6251. Fax: +82 31 299 6269. E-mail: kongy@skku.edu

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