Restriction map of 4.9-kb λ phage insert digested with
XbaI and subcloned into pZErO (A), and nucleotide sequence
of C. immitis BGL2 gene and deduced amino acid sequence
(B). The 423-bp probe in panel A is derived from PCR product (a) in
Fig. 1. The two underlined amino acid sequences represent matched
peptide sequence of the Lys-C-digested, native 120-kDa
glycoprotein. The amino acid sequence in boldface type (aa
559 to 577) matched the peptide sequence of Lys-C-digested recombinant
BGL2. The boxed sequence represents the 18-aa signature motif of family
3 glycosyl hydrolases. The aspartic acid residue within this sequence
(boldface type) is the putative active site. Residues contained within
square brackets are putative N glycosylation sites. The
arrow between aa 18 and 19 indicates a putative cleavage site of the
signal peptide. The double-underlined nucleotide sequences indicate
conserved 5′-3′ sequences of introns. The gene-specific primers used
for RACE and RT-PCR are indicated. The putative CAAT box (boldface
type), 5′ end of the UTR (c̊), stop codon (asterisk), and putative
poly(A) addition sites (•) are also indicated.