NUCLEOTIDE-SEQUENCE AND PHYLOGENETIC ANALYSIS OF THE MEDIUM (M) GENOMIC RNA SEGMENTS OF 3 HANTAVIRUSES ISOLATED IN CHINA

The medium (M) genome segment of hantaviruses (family Bunyaviridae) en codes the two virion glycoproteins, G1 and G2, as a precursor protein in the complementary sense RNA. We determined the nucleotide sequences of the M genome segments of three Chinese hantavirus isolates, a Hant aan-type (HTN) virus designated A9 and two Seoul-type (SEO) viruses de signated L99 and HB55, and compared them to those of other HTN or SEO viruses isolated in Eastern Asia. The M segment of A9 is 3616 nucleoti des in length and shows 99.5% identity at the nucleotide level and 99. 1% identity at the amino acid level to that of the Chinese HTN isolate HV114. The M segments of L99 and HB55 are 3652 nucleotides in length, one nucleotide longer than the M segments of other sequenced SEO isol ates such as SEO 80-39, SR-11, and Biken-1. The Chinese SEO isolates s howed 95% nucleotide sequence identity and 99% amino acid sequence ide ntity to SEO 80-39. We also sequenced a 736 nucleotides region of the M genome segment of another Chinese SEO isolate, R22, which revealed e rrors in the published data. Phylogenetic analysis of the available se quences indicated that both the Chinese HTN- and SEO-type viruses form lineages distinct from those of the isolates from other parts of East ern Asia. (C) 1998 Elsevier Science B.V. All rights reserved.