Anti-σ factor: Members of ECF35 might be regulated by a putative AS factor encoded in position +1. This AS factor contains one transmembrane helix (67.68%, ~100% when looking at an MSA) and periplasmic tetratricopeptide repeats in some cases. Members of subgroups ECF35s17, ECF35s12, ECF35s1, ECF35s6, ECF35s14, ECF35s20 and ECF35s4 contain an average of ~1 protein with a DUF3520 in their genetic context, usually in positions -1 of -2. These proteins were identified as putative AS factors in groups ECF226 and ECF289, where they are fused to von Willebrand factors. Nevertheless, DUF3520-containing proteins do not bear any transmembrane helix when associated with members of ECF35.
Genomic context conservation: Other conserved domains include a UPF0029 (+2 of ECF35s2), the C-terminal domain of a TonB protein (-1 of ECF35s13), a diguanylate cyclase with an EAL and a GAF domain (-1 of ECF35s2), an oligopeptide/dipeptide ABC transporter (ECF35s11), a protein with a transglycosylase SLT domain (ECF35s7) and an AIR carboxylase (ECF35s7).
Studied members: A characterized member of ECF35 is SbrI from Pseudomonas aeruginosa (ECF35s1). SbrI is involved in cell envelope integrity in the control of swarming motility and biofilm formation. It is inhibited by the AS factor SbrR, encoded in +1 in the same operon (see review (Chevalier et al., 2018)).
Promoter motif conservation: Predicted target promoter motifs are subgroup-dependent. Subgroups ECF35s2 and ECF35s5 contain ACCC in -35 and CGT in -10, whereas subgroups ECF35s1 and ECF35s6 contain TAACCCG in -35 and CGTCT in -10. Indeed, this last motif agrees with the binding promoter motif of SbrI (Aires, Köhler, Nikaido, & Plésiat, 1999).
Summary: ECF35 is regulated by one-transmembrane helix AS factors encoded in +1. Members of this group might be involved in the control of swarming motility, biofilm formation and cell envelope integrity as in the case of SbrI from P. aeruginosa (ECF35s1).
Number of representative ECFs: 835
Number of non-redundant ECFs: 1027
Sequences with C-terminal extension: 0.00%
Sequences with N-terminal extension: 3.60%
Overrepresented phylum: Proteobacteria [99.88%]
|Involvement of an active efflux system in the natural resistance of Pseudomonas aeruginosa to aminoglycosides.||Antimicrobial agents and chemotherapy||1999||J. Aires, T. Köhler, H. Nikaido, P. Plésiat||PubMed: 10543738||ECF35|
|Extracytoplasmic function sigma factors in Pseudomonas aeruginosa.||Biochimica et biophysica acta. Gene regulatory mechanisms||2018||S. Chevalier, E. Bouffartigues, A. Bazire, A. Tahrioui, R. Duchesne, D. Tortuel, O. Maillot, T. Clamens, N. Orange, M. Feuilloley, O. Lesouhaitier, A. Dufour, P. Cornelis||PubMed: 29729420||ECF02, ECF102, ECF243, ECF293, ECF35|