关键词: 猪嗜血支原体, 果糖-1,6-二磷酸醛缩酶, 原核表达, 纯化

Abstract: Mycoplasma suis is a pathogenic microorganism that is attached to the surface of the porcine erythrocyte membrane, free in plasma, or parasitized in bone marrow. The infection is characterized by anemia, fever, and jaundice as the main clinical symptoms, with a high lethality in the acute stage, resulting in significant economic losses to the livestock production industry. Mycoplasma relies on the glycolytic pathway for energy supply, and fructose-1,6-bisphosphate aldolase (FBA) is a key enzyme in the glycolytic pathway with many capabilities beyond its catalytic function. Prokaryotic expression and purification of fructose-1,6-bisphosphate aldolase (FBA) of Mycoplasma suis, construction of recombinant expression plasmid pET28a(+)-FBA, transformation of transetta receptor cells, induced expression with IPTG, detection of the expression product by using the Western-blot method were done, and the recombinant protein concentration was measured by the BCA method after the expression product was purified by nickel ion affinity chromatography. The results showed that: the prokaryotic expression vector was successfully constructed by double zymography identification and induced expression in DE3; the recombinant protein had a relative molecular mass of 31.5 ku, and it was expressed in both precipitation and supernatant; the purified target protein was obtained by nickel-ion affinity chromatography, and the concentration of the recombinant protein after dialysis and ultrafiltration treatment was 0.48 mg/mL. It can be utilized to investigate the role of FBA in Mycoplasma suis, as a possible vaccine or chemotherapeutic target.

Key words: Mycoplasma suis, fructose-1,6-bisphosphate aldolase, prokaryotic expression, purification