Fig. 1. Sequence analysis of the chlamydial isolates examined in this study. For each isolate, the strain designation is indicated in the left column and the accession number for the incA sequence is indicated in the right column. The complete incA sequence was determined for the isolates shown in bold, whereas the first 450–500 nt were analysed for all other isolates. The sequences of incA from five additional wild-type isolates (E9332, J2364, J3464, J9311 and J9325) were identical to that of the serovar D sequence in the Chlamydia genome-project database (Stephens et al., 1998 ), and these sequences are not represented in the figure. One recent IncA-positive variant, J(s)9045, was not subjected to sequence analysis. The results of the fluorescence-microscopy analysis are listed under IncA IF, with a + indicating labelling of the IM in cells infected with the isolate. The length of the IncA sequence in the ORF predicted from the nucleotide-sequence analysis is indicated by the open bar for each isolate. , Silent base changes in incA; *, a base change that leads to an amino-acid substitution; , single base deletions or insertions that lead to premature truncation of the protein; , single base changes that lead directly to a stop codon. Solid bars indicate larger deletions and are drawn to scale.