Biochemical and biophysical analysis of heptad repeat regions from the fusion protein of Menangle virus, a newly emergent paramyxovirus

• Published in: Archives of virology 2003-07, Vol.148 (7), p.1301-1316
• Main Authors: ZHU, J. Q, ZHANG, C. W.-H, RAO, Z, TIEN, P, GAO, G. F
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Australia; Base Sequence; Binding Sites; Biological and medical sciences; Circular Dichroism; DNA Primers; Fundamental and applied biological sciences. Psychology; Genes, Synthetic; Genomes; Influenza; Microbiology; Models, Molecular; Molecular Sequence Data; Morphology, structure, chemical composition, physicochemical properties; Pathogens; Peptide Fragments - chemistry; Peptides; Protein Structure, Secondary; Proteins; Recombinant Fusion Proteins - chemistry; Recombinant Fusion Proteins - metabolism; Repetitive Sequences, Amino Acid; Respirovirus - classification; Respirovirus - genetics; Respirovirus - isolation & purification; Viral Proteins - chemistry; Viral Proteins - genetics; Viral Proteins - metabolism; Virology; Viruses; Zoonoses
• ISSN: 0304-8608; 1432-8798
• DOI: 10.1007/s00705-003-0105-x

Menangle virus is a novel paramyxovirus isolated in Australia in 1997, but its classification position has not yet been finally settled. Here by using a computational program, LearnCoil-VMF, we determined the heptad repeat (HR) regions (HR1 and HR2) of Menangle virus F protein. Subsequently the HR1 and HR2 peptides were expressed as a single chain (named 2-Helix) connected by a six amino-acid linker as a GST fusion protein with an E. coli in vitro expression system. The GST-removed purified 2-Helix protein could form a stable trimer in vitro judging by gel-filtration and chemical cross-linking. CD spectra showed that the 2-Helix protein had a high percentage of alpha-helix and was very thermo-stable. Crystals of the 2-Helix protein preparations have been obtained in many conditions with hanging-drop diffusion method. These results indicated that Menangle virus has the common features of the fusion protein for other paramyxoviruses and should adopt a similar fusion mechanism to other members. As the HR regions of Menangle virus F protein could form stable six-helix bundle coiled coil structure, they should be used as drug target for the design of fusion inhibitors, as successfully used for other parmyxoviruses. This is especially relevant to such a newly emergent virus with zoonotic potentials.