Databases and Systems

Figure 2: Distribution of families according to the number of sequences they contain
(without redundancy) [HOVERGEN release 25, July 1997].
Protein multiple alignment and phylogenetic trees
Protein multiple alignments are computed with CLUSTALV [20] for each gene
family, except those that contain more than 150 sequences (Table 1). When several
redundant CDSs are available, only one is included in the alignment. Phylogenetic
trees are inferred from multiple alignments using the 'neighbor joining' method [21].
Updating of data and rate of growth
HOVERGEN is updated every two GenBank releases (every four months). New or
modified sequences from GenBank are compared to HOVERGEN sequences and
between each others, first at the DNA level to identify redundancy, and then at the
protein level to update the classification. Multiple alignments and phylogenetic trees
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