Global genetic diversity of human metapneumovirus fusion gene

Abstract

We analyzed 64 human metapneumovirus strains from eight countries. Phylogenetic analysis identified two groups (A and B, amino acid identity 93%-96%) and four subgroups. Although group A strains predominated, accounting for 69% of all strains, as many B as A strains were found in persons >3 years of age.

Figure 1

Phylogenetic analysis of the fusion (F) gene of 64 human metapneumovirus (HMPV) strains recovered from various countries (CAN, Canada; RSA, Republic of South Africa; FRA, France; AUS, Australia; NETH, the Netherlands). Neighbor-Joining consensus tree was obtained from the nucleic acid alignment representing nucleotides 60–708 of the HMPV prototype sequence NETH-001. Numbers represent the frequency of occurrence of nodes in 500 bootstrap replicas.

Figure 2

Amino acid sequence alignment of the fusion (F) protein of various human metapneumovirus (HMPV) strains and other paramyxoviruses. Amino acid numbering is based on the sequence of the HMPV strain NETH-001 (GenBank accession no. AF371337). Amino acids shown are those different than NETH-001. Boxed residues represent conserved cysteines. Potential N-glycosylation sites are underlined. The fusion domain is indicated by italics in the consensus sequence, whereas the heptad repeat A region is indicated by bold characters. Shaded residues represent significant substitutions between HMPV groups and subgroups. Note that only distinct HMPV strains were included in the alignment. PVM, pneumonia virus of mice; BRSV, bovine respiratory syncytial virus; HRSV, human respiratory syncytial virus; APV, avian pneumovirus; RSA, Republic of South Africa; CAN, Canada; FRA, France; AUS, Australia; NETH, the Netherlands.