Immunoprotection of chickens against Eimeria acervulina by recombinant α-tubulin protein

Abstract

Tubulins are heterodimeric molecules responsible for the polymerization of microtubules in apicomplexan parasites. The alpha-tubulin, a subcellular structural protein of Eimeria acervulina, was cloned and expressed in Escherichia coli as an alpha-tubulin-GST fusion protein. Immunogenicity of the recombinant protein was studied in chickens by subcutaneous injection of 50, 100, or 150 microg of the protein with or without Freund's adjuvant. Immunization with 150 microg alpha-tubulin-GST protein in combination with Freund's adjuvant conferred partial protection against E. acervulina oocyst challenge, as shown by a 36% reduction in oocyst shedding, a marked decrease in intestinal lesion score and a significant increase in body weight gain in comparison with the nonimmunized controls. The results suggest that alpha-tubulin protein may be used as an effective vaccine antigen for the control of Eimeria infection.

Expression of recombinant alpha and beta tubulins from the yew Taxus cuspidata and analysis of the microtubule assembly in the presence of taxol

“…13) Most of those residues were well conserved between the different species. However, 26 Glu was only shared by T. cuspidata, T. baccata, and E. grandis. In addition, 359 Typ and 361…”

“…3(B), taxol at a concentration of 1.0 μM (solid line with open circles) or 10 μM (solid line with closed circles) did not cause an increase in OD 350 compared with the control (MeOH, solid line), clearly indicating that the microtubule assembly was suppressed. The mutant carrying 26 Asp instead of Glu (E26D) exhibited higher sensitivity toward taxol than the wild type (Fig. 3(C)).…”

“…3(D)), suggesting that the mutation at W359 may not affect taxol binding. Thus, the reduced binding affinity to taxol of the Taxus microtubule was achieved by the variation at 26 Glu in the beta tubulin, which would infer a self-defense mechanism for T. cuspidata. Notes: (A) The extracted amino acid sequences of the beta tubulins from HEK293T cells and plants were aligned.…”

“…2(B)). [25][26][27] Lanes 1 and 2 present the mixture of the alpha and beta tubulins from T. cuspidata and HEK293T cells, respectively. The sizes of the two bands are ca.…”

“…Modeling studies based on the crystal structure of the taxol and beta tubulin complex projected the interaction site of taxol. 13,14) The 23 Val in the H1 helix forms a hydrophobic interaction with both of the N′ and 3′ phenyl rings, and 26 Asp is positioned within hydrogen bonding distance from the nitrogen group in the side chain. In the H6-H7 loop, 215 Leu and 217 Leu form hydrophobic interactions with the 2-phenyl ring, which is located near 227 His and 228 Leu in helix H7.…”