title: [Studies on the spectral characteristics of efficient HIV-1 fusion inhibitor C22].
abstract: Acquired immune deficiency syndrome (AIDS) is increasing its negative influences on human society and economy. In the present paper, HIV-1 cell fusion peptide inhibitor C22 was expressed and purified based on the C-terminal sequence of HIV-1 membrane fusion glycoprotein gp41. The gene coding for C22 was totally synthesized using gp41 gene as a template and amplified by PCR The cloned C22 gene was confirmed by restriction endonuclease and sequence analysis and then cloned into plasmid pTMHa30-51. The prepared plasmid was transformed into E. coli BL21 (DE3) and the expressing products were analyzed on SDS-PAGE and tested with mass spectrum. The results indicated that C22 showed high HIV-1 fusion inhibiting capacity, meanwhile, with good thermal stability and water-solubility, and showed no cell toxicity in tested concentrations. The spectral characteristics were tested with circular dichroism (CD). When treated at different temperature in solution condition, the content of a helix of C22 increased at 37 degrees C while decreased sharply at 80 degrees C. The peak value changed significantly with different pH values. The content of a helix of C22 decreased as pH varied toward acid and alkali and the random coiling increased, which led to a relaxed structure. This result indicated that the C22 structure is stable with pH 6. This research may provide a theoretic foundation for the new type HIV-1 peptide inhibitor designing and spectral characteristics study.
authors.affiliation: School of Life Science and Technology, Tongji University, Shanghai 200092, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Shi
authors.forename: Jiao-juan
authors.initials: JJ
authors.lastname: He
authors.forename: Shi-long
authors.initials: SL
authors.lastname: Wang
authors.forename: Xiao-Yu
authors.initials: XY
authors.lastname: Sun
authors.forename: Qing-Yu
authors.initials: QY
authors.lastname: Chen
mesh_terms: D000595:Amino Acid Sequence; D004269:DNA, Bacterial; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli; D015700:HIV Envelope Protein gp41 / Q000737:chemistry*; D023581:HIV Fusion Inhibitors / Q000737:chemistry*; D015497:HIV-1 / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D013058:Mass Spectrometry; D010446:Peptide Fragments / Q000032:analysis / Q000737:chemistry*; D010957:Plasmids; D016133:Polymerase Chain Reaction; D015202:Protein Engineering / Q000379:methods
chemical_list: D004269:DNA, Bacterial; D015700:HIV Envelope Protein gp41; D023581:HIV Fusion Inhibitors; D010446:Peptide Fragments