9 research outputs found

    Crystallization and preliminary X-ray analysis of \u3ci\u3eNa\u3c/i\u3e-ASP-1, a multi-domain pathogenesis-related-1 protein from the human hookworm parasite \u3ci\u3eNecator americanus\u3c/i\u3e

    Get PDF
    Human hookworm infection is a major cause of anemia and malnutrition in the developing world. In an effort to control hookworm infection, the Human Hookworm Vaccine Initiative has identified candidate vaccine antigens from the infective larval stage (L3) of the parasite, including a family of pathogenesis-related-1 (PR-1) proteins known as the ancylostoma-secreted proteins (ASPs). The functions of the ASPs are unknown. In addition, it is unclear why some ASPs have one while others have multiple PR-1 domains. There are no known structures of a multi-domain ASP and in an effort to remedy this situation, recombinant Na-ASP-1 has been expressed, purified and crystallized. Na-ASP-1 is a 406-amino-acid multi-domain ASP from the prevalent human hookworm parasite Necator americanus. Useful X-ray data to 2.2 A ° have been collected from a crystal that belongs to the monoclinic space group P21 with unit-cell parameters a = 67.7, b = 74.27, c = 84.60 Å, β = 112.12°. An initial molecular-replacement solution has been obtained with one monomer in the asymmetric unit

    Crystallization and preliminary X-ray analysis of \u3ci\u3eNa\u3c/i\u3e-ASP-1, a multi-domain pathogenesis-related-1 protein from the human hookworm parasite \u3ci\u3eNecator americanus\u3c/i\u3e

    Get PDF
    Human hookworm infection is a major cause of anemia and malnutrition in the developing world. In an effort to control hookworm infection, the Human Hookworm Vaccine Initiative has identified candidate vaccine antigens from the infective larval stage (L3) of the parasite, including a family of pathogenesis-related-1 (PR-1) proteins known as the ancylostoma-secreted proteins (ASPs). The functions of the ASPs are unknown. In addition, it is unclear why some ASPs have one while others have multiple PR-1 domains. There are no known structures of a multi-domain ASP and in an effort to remedy this situation, recombinant Na-ASP-1 has been expressed, purified and crystallized. Na-ASP-1 is a 406-amino-acid multi-domain ASP from the prevalent human hookworm parasite Necator americanus. Useful X-ray data to 2.2 A ° have been collected from a crystal that belongs to the monoclinic space group P21 with unit-cell parameters a = 67.7, b = 74.27, c = 84.60 Å, β = 112.12°. An initial molecular-replacement solution has been obtained with one monomer in the asymmetric unit

    Cell bank characterization and fermentation optimization for production of recombinant heavy chain C-terminal fragment of botulinum neurotoxin serotype E (rBoNTE(H\u3csub\u3ec\u3c/sub\u3e): Antigen E) by \u3ci\u3ePichia pastoris\u3c/i\u3e

    Get PDF
    A process was developed for production of a candidate vaccine antigen, recombinant C-terminal heavy chain fragment of the botulinum neurotoxin serotype E, rBoNTE(Hc)in Pichia pastoris. P. pastoris strain GS115 was transformed with the rBoNTE(Hc) gene inserted into pHILD4 Escherichia coli—P. pastoris shuttle plasmid. The clone was characterized for genetic stability, copy number, and BoNTE(Hc) sequence. Expression of rBoNTE(Hc) from the Mut+ HIS4 clone was confirmed in the shake-flask, prior to developing a fed-batch fermentation process at 5 and 19 L scale. The fermentation process consists of a glycerol growth phase in batch and fed-batch mode using a defined medium followed by a glycerol/methanol transition phase for adaptation to growth on methanol and a methanol induction phase resulting in the production of rBoNTE(Hc). Specific growth rate, ratio of growth to induction phase, and time of induction were critical for optimal rBoNTE(Hc) production and minimal proteolytic degradation. A computer-controlled exponential growth model was used for process automation and off-gas analysis was used for process monitoring. The optimized process had an induction time of 9 h on methanol and produced up to 3 mg of rBoNTE(Hc) per gram wet cell mass as determined by HPLC and Western blot analysis

    Cell bank characterization and fermentation optimization for production of recombinant heavy chain C-terminal fragment of botulinum neurotoxin serotype E (rBoNTE(H\u3csub\u3ec\u3c/sub\u3e): Antigen E) by \u3ci\u3ePichia pastoris\u3c/i\u3e

    Get PDF
    A process was developed for production of a candidate vaccine antigen, recombinant C-terminal heavy chain fragment of the botulinum neurotoxin serotype E, rBoNTE(Hc)in Pichia pastoris. P. pastoris strain GS115 was transformed with the rBoNTE(Hc) gene inserted into pHILD4 Escherichia coli—P. pastoris shuttle plasmid. The clone was characterized for genetic stability, copy number, and BoNTE(Hc) sequence. Expression of rBoNTE(Hc) from the Mut+ HIS4 clone was confirmed in the shake-flask, prior to developing a fed-batch fermentation process at 5 and 19 L scale. The fermentation process consists of a glycerol growth phase in batch and fed-batch mode using a defined medium followed by a glycerol/methanol transition phase for adaptation to growth on methanol and a methanol induction phase resulting in the production of rBoNTE(Hc). Specific growth rate, ratio of growth to induction phase, and time of induction were critical for optimal rBoNTE(Hc) production and minimal proteolytic degradation. A computer-controlled exponential growth model was used for process automation and off-gas analysis was used for process monitoring. The optimized process had an induction time of 9 h on methanol and produced up to 3 mg of rBoNTE(Hc) per gram wet cell mass as determined by HPLC and Western blot analysis

    Purification of a recombinant heavy chain fragment C vaccine candidate against botulinum serotype C neurotoxin [rBoNTC(H\u3csub\u3ec\u3c/sub\u3e)] expressed in \u3ci\u3ePichia pastoris\u3c/i\u3e

    Get PDF
    A purification process for the manufacture of a recombinant C-terminus heavy chain fragment from botulinum neurotoxin serotype C [rBoNTC(Hc)], a potential vaccine candidate, has been defined and successfully scaled-up. The rBoNTC(Hc) was produced intracellularly in Pichia pastoris X-33 using a three step fermentation process, i.e., glycerol batch phase, a glycerol fed-batch phase to achieve high cell densities, followed by a methanol induction phase. The rBoNTC(Hc) was captured from the soluble protein fraction of cell lysate using hydrophobic charge induction chromatography (HCIC; MEP HyperCel™), and then further purified using a CM 650M ion exchange chromatography step followed by a polishing step using HCIC once again. Method development at the bench scale was achieved using 5–100 mL columns and the process was performed at the pilot scale using 0.6–1.6 L columns in preparation for technology transfer to cGMP manufacturing. The process yielded approximately 2.5 g of rBoNTC(Hc)/kg wet cell - weight (WCW) at the bench scale and 1.6 g rBoNTC(Hc)/kg WCW at the pilot scale. The purified rBoNTC(Hc) was stable for at least 3 months at 5 and -80 °C as determined by reverse phase-HPLC and SDS–PAGE and was stable for 24 months at -80 °C based on mouse potency bioassay. N-Terminal amino acid sequencing confirmed that the N-terminus of the purified rBoNTC(Hc) was intact

    Purification and Scale-Up of a Recombinant Heavy Chain Fragment C of Botulinum Neurotoxin Serotype E in \u3ci\u3ePichia Pastoris\u3c/i\u3e GS115

    Get PDF
    A recombinant C-terminus heavy chain fragment from botulinum neurotoxin serotype E (BoNT/E) is proposed as a vaccine against the serotype E neurotoxin. This fragment, rBoNTE(Hc), was produced intracellular in Pichia pastoris GS115 by a three-step fermentation process, i.e., glycerol batch phase and a glycerol fed-batch phase to achieve high cell densities, followed by a methanol fed-batch induction phase. The rBoNTE(Hc) protein was purified from the soluble fraction of cell lysates using three ion-exchange chromatography steps (SP Sepharose Fast Flow, Q Sepharose Fast Flow, Sp Sepharose High Performance) and polished with a hydrophobic charge induction chromatography step (MEP HyperCel). Method development at the bench scale was achieved using 7– 380 mL columns and the process was performed at the pilot scale using 0.5–3.1 L columns in preparation for technology transfer to cGMP manufacturing. The purification process resulted in greater than 98% pure rBoNTE(Hc) based on HPLC and yielded up to 1.01 g of rBoNTE(Hc)/kg cells at the bench scale and 580mg vaccine/kg cells at the pilot scale. N-terminal sequencing showed that the purified rBoNTE(Hc) N-terminus is intact and was found to protect mice against a challenge of 1000 mouse intraperitoneal LD50’s of BoNT/E

    Purification and scale-up of a recombinant heavy chain fragment C of botulinum neurotoxin serotype E in Pichia pastoris GS115

    Get PDF
    A recombinant C-terminus heavy chain fragment from botulinum neurotoxin serotype E (BoNT/E) is proposed as a vaccine against the serotype E neurotoxin. This fragment, rBoNTE(Hc), was produced intracellular in Pichia pastoris GS115 by a three-step fermentation process, i.e., glycerol batch phase and a glycerol fed-batch phase to achieve high cell densities, followed by a methanol fed-batch induction phase. The rBoNTE(Hc) protein was purified from the soluble fraction of cell lysates using three ion-exchange chromatography steps (SP Sepharose Fast Flow, Q Sepharose Fast Flow, Sp Sepharose High Performance) and polished with a hydrophobic charge induction chromatography step (MEP HyperCel). Method development at the bench scale was achieved using 7– 380 mL columns and the process was performed at the pilot scale using 0.5–3.1 L columns in preparation for technology transfer to cGMP manufacturing. The purification process resulted in greater than 98% pure rBoNTE(Hc) based on HPLC and yielded up to 1.01 g of rBoNTE(Hc)/kg cells at the bench scale and 580 mg vaccine/kg cells at the pilot scale. N-terminal sequencing showed that the purified rBoNTE(Hc) N-terminus is intact and was found to protect mice against a challenge of 1000 mouse intraperitoneal LD50’s of BoNT/E

    Crystallization and preliminary X-ray analysis of Na-ASP-1, a multi-domain pathogenesis-related-1 protein from the human hookworm parasite Necator americanus

    Get PDF
    In order to clarify the structural basis of the pathogenesis-related-1 domain, Na-ASP-1, the first multi-domain ASP from the human hookworm parasite N. americanus, has been crystallized. 2.2 Å resolution data have been collected from a crystal belonging to the monoclinic space group P21
    corecore