Duplicated sporulation genes in bacteria

This is the authors' abstract. We don't add key points for this paper.

Statistical analysis indicates that about 150 genes might be needed for spore formation in Bacillus subtilis [1]. We have sequenced 11 of these and examined the predicted amino acid sequences for the possibility that present‐day sporulating bacteria may have evolved from ancestral forms in which sporulation was governed by a smaller number of genes. We have identified two pairs of duplicated genes. The first of them involves a sequence which shows major homologies with both the sigma factor (σ) of RNA polymerase in Escherichia coli and σ 29 in B. subtilis . Another example of homology involves no less than 4 separate genes coding for the acid‐soluble proteins of the spore [2]. We conclude that sporulation may have evolved from a much smaller number of genes that we first envisaged and it is likely, anyway, to be no more complex than replication of the larger coliphages.