General description: Members of this group have homology members of original ECF20 (95.41%) and appear in Proteobacteria (97.64%) and Planctomycetes (2.36% of the total) from family Planctomycetaceae.
Anti-σ factor: Proteins in +1 are putative AS factors (except in ECF290s3) and harbor one transmembrane helix (42.54%, ~100% of the sequences from subgroups except for ECF290s3 in an MSA). These proteins do not appear in ECF290s3, which contains the coding sequence of flagellin instead.
Genomic context conservation: Conserved proteins encoded in the context of ECF290 include a membrane-bound heavy-metal resistance protein (+2 of ECF290s1 and ECF290s2), a diguanylate cyclase fused to a response regulator receiver domain (+3 of ECF290s2), an EF-hand (-1 of ECF290s2), a DUF983 (-2 of ECF290s2), a NUDIX domain (-3 of ECF290s2) from nucleoside diphosphate hydrolases. This genetic context, and especially the metal-resistance protein encoded in +2, is conserved in most groups from ECF290. Nevertheless, members of subgroup ECF290s3 are encoded near proteins involved in flagellum biosynthesis such as flagellin in +1, flagellar hook-associated protein 2 in +2 and FliS in +3.
Promoter motif conservation: Predicted target promoter motifs have low information content. The largest subgroups, ECF290s1 and ECF290s2, share an ACGG in -35 and CGT is conserved in several -10 elements. These motifs agree with the original group ECF20 (Staroń et al., 2009).
Summary: Members of ECF290 are associated with putative AS factors usually encoded in position +1. These putative AS factors contain one transmembrane helix and no Pfam domain. A conserved heavy metal resistance protein is encoded in +2, which points to metal detoxification as the function of members of ECF290. Subgroup ECF290s3 does not seem to encode any AS factor in its genomic context, and it contains proteins for the synthesis of the flagellum instead.
Number of representative ECFs: 838
Number of non-redundant ECFs: 980
Sequences with C-terminal extension: 0.20%
Sequences with N-terminal extension: 14.29%
Overrepresented phylum: Proteobacteria [98.57%]