Full Length Research Paper

Comparative analysis of human coronavirus-NL63 ORF3 protein homologues

Burtram C. Fielding* and Tasnim Suliman

Molecular Virology Laboratory, Department of Medical BioSciences, University of the Western Cape, Department of Natural Sciences, Western Cape, South Africa.

*Corresponding author. E-mail: bfielding@uwc.ac.za. Tel: 27-21-959 3620.

Fax: 27-21-959 1339.

Accepted 17 April, 2009

   Abstract

It has been reported in some studies that the newly discovered human coronavirus NL-63 (HCoV-NL63) is one of the most common coronaviruses associated with acute respiratory infections. HCoV-NL63 was first isolated in 2004 from a 7 month old infant in Holland. The HCoV-NL63 genome encodes for one accessory protein, ORF3. This reports the computational analysis of human coronavirus NL63 ORF3 by comparing the amino acid sequences of coronavirus ORF3-homologues. The HCoV-NL63 ORF3 gene was found to encode a putative protein ~25.6 kDa in size. ORF3 was predicted to contain three potential transmembrane regions. The amino acid sequence of HCoV-NL63 ORF3 was shown to be most similar to HCoV 229E ORF4 (43% identity; 62% similarity).

Key words: Human coronavirus, NL-63, accessory protein ORF3, gene analysis.