Characterization of fructose-1, 6-bisphosphate aldolase in <i>Dermacentor silvarum</i>

Fructose-1, 6-bisphosphate aldolase (FBA) catalyses the conversion of fructose-1, 6-diphosphatein to dihydroxyacetone phosphate and glyceraldehyde-3-phosphate. It is an important enzyme for both glycolysis and gluconeogenesis in parasites. In this study, we cloned the open reading frame of the FBA gene from <i>Dermacentor silvarum</i>, which was 1095 bp and encoded a protein of 364 amino acids. The deduced amino acid sequence of <i>D. silvarum</i> FBA had high similarity with FBA homologues from other ticks. Phylogenetic analysis of FBA showed that <i>D. silvarum</i> and <i>Amblyomma variegatum</i> belonged to the same clade. The recombinant FBA of <i>D. silvarum</i> (rDsFBA) was expressed in <i>Escherichia coli</i> and the molecular weight was about 62 kDa, which was abundantly expressed in the supernatant of <i>E. coli</i> following induction by 0.5 mM IPTG for 8 h at 25°C. The activity of rDsFBA was characterized using a coupled enzymatic assay. The rDsFBA had a Km of 21.22 μM and a Vmax of 1.57 U/mg. Western blot analysis demonstrated that rDsFBA could be recognized by rabbit anti<i>-D. silvarum</i> polyclonal antibodies, suggesting it probably owned immunogenicity. The data reported here contribute to future research into the role of FBA in <i>D. silvarum</i>, and provides a new candidate antigen for controlling tick.