Fig. 1
Identification of Hp-TGM. a Fractionation of HES by gel filtration FPLC. 1 mg of HES was separated on a Superdex 200 10/300 GL column and 1 ml fractions collected for assay with MFB-F11 reporter cells; responses were calibrated with recombinant human TGF-β1. b as a, fractionation by ion exchange FPLC on a Mono QTM 5/50 G column. c Abundance of a candidate protein, Hp_I03161_IG00349_L1408, calculated by the exponentially modified Protein Abundance Index (emPAI) in each fraction, compared to the activation of TGFβ-responsive cells by the same fraction. d TGF-β bioassay screen of four candidate recombinant clones designated A–D; clone B corresponds to candidate Hp_I03161_IG00349_L1408 shown in panel c. Supernatants of cells transfected with clones A–D were assayed in duplicate, and mean values ± SEM are shown. Two-tailed t tests found Clone B to be significantly (p < 0.05) higher than all others. e Alignment of five similar domains within Hp-TGM encompassing the entire amino acid sequence apart from the predicted signal peptide (aa 1–18), with conserved cysteine (white on red) and other residues indicated, together with a Complement Control Protein (CCP) module from the nematode Ascaris suum (domain 12 of ASU_08405, aa 954–1018), and an archetypal CCP domain, human Factor H module 1 (X07523, aa 20–83). Other conserved residues are shown in red and potential N-glycosylation sites outlined in green. Amino acid positions for each domain of Hp-TGM are indicated on the left. Note the presence of a 15-aa insertion near the N-terminal of each domain of Hp-TGM which is not typical of the CCP family. Positions of disulfide bonds in Factor H are shown below the alignment by linked cysteine residues CI – CIV. f Exon-intron structure of Hp-TGM in the H. polygyrus genome; domains are colored corresponding to symbols in panel e; positions of cysteine residues indicated in black circles
