title: Molecular characterization of a Brugia malayi transglutaminase.
abstract: Prior studies have demonstrated that transglutaminase (TGase) from the human filarial parasite Brugia malayi is critical for the growth and development of the larval stages. In this report, we describe the cloning and partial characterization of a cDNA encoding the B. malayi TGase (BmTGase). Using RT-PCR and RACE-PCR, the cDNA was amplified from adult worm mRNA. BmTGase is 1,881 bp long and codes for a protein with a predicted molecular mass of 54 kDa. Amino acid sequence analysis of BmTGase revealed significant homology to the protein disulfide isomerase (PDI), particularly, to the PDI-related protein ERp60, a PDI isoform found in the lumen of endoplasmic reticulum. The activity of recombinant B. malayi TGase enzyme (rBmTG) was found to be calcium-dependent and could be inhibited by EDTA. ELISA studies showed that approximately 88% of 48 sera from healthy Indian patients living in a bancroftian filariasis endemic area were reactive with rBmTG. In contrast, only 33% of sera from patients with clinical filariasis were reactive to rBmTG. Non-endemic sera were uniformly non-reactive. Additional studies are needed to elucidate the role, if any, of B. malayi TGase in protective immunity to filariasis.
authors.affiliation: Department of Bioimmunotherapy, M.D. Anderson Cancer Center, University of Texas, 1515 Holocombe Blvd., TX 77030, Houston, USA.
authors.forename: Eswaran
authors.initials: E
authors.lastname: Devarajan
authors.forename: Pankaj Kumar
authors.initials: PK
authors.lastname: Mishra
authors.forename: Shiva
authors.initials: S
authors.lastname: Thirugnanam
authors.forename: Kapil
authors.initials: K
authors.lastname: Mehta
authors.forename: Ramaswamy
authors.initials: R
authors.lastname: Chandrashekar
authors.forename: Kaliraj
authors.initials: K
authors.lastname: Perumal
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D017178:Brugia malayi / Q000201:enzymology* / Q000235:genetics; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005368:Filariasis / Q000276:immunology / Q000469:parasitology; D006801:Humans; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D011503:Transglutaminases / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D000909:Antibodies, Helminth; D018076:DNA, Complementary; D011994:Recombinant Proteins; D011503:Transglutaminases