title: [Purification and structural analysis of the nucleocapsid of PRRS virus expressed from Escherichia coli].
abstract: The DNA fragment encoding the nucleocapsid protein (N) of PRRSV BJ4 strain were cloned into the BamH I / EcoR I sites of pET28a vector to construct the expression plasmid pET28-N by designing special primers. The soluble protein (P28-N) were obtained by introducing the expression plasmid into E. coli BL21 (DE3) host cell, and the amount of recombinant protein reached to 28% of the total mass of bacterial protein. PET28-N were purified by nickel-affinity column of Proband resin. The circular dichroism (CD) analysis showed that the purified PET28-N shared a significant (26%) alpha-helical structure, beta-sheet (23.7%), beta-turn (19.8%), and random coil (30.3%), respectively. Finally,the secondary structure of N protein of PRRSV was deduced.
authors.affiliation: Key Laboratory of Preventive Veterinary Medicine of Ministry of Agriculture, College of Veterinary Medicine, China Agirictural University, Beijing 100094, China.
authors.forename: Jin-Hai
authors.initials: JH
authors.lastname: Huang
authors.forename: Han-Chun
authors.initials: HC
authors.lastname: Yang
authors.forename: Xin
authors.initials: X
authors.lastname: Guo
authors.forename: Yan-Hong
authors.initials: YH
authors.lastname: Chen
authors.forename: Zhen-Lin
authors.initials: ZL
authors.lastname: Zha
mesh_terms: D002942:Circular Dichroism; D004926:Escherichia coli / Q000235:genetics; D019590:Nucleocapsid Proteins / Q000737:chemistry / Q000302:isolation & purification*; D019316:Porcine respiratory and reproductive syndrome virus / Q000737:chemistry*; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D019590:Nucleocapsid Proteins; D011994:Recombinant Proteins