General description: Two subgroups of ECF25, ECF25s1 and ECF25s11, have homology to original ECF25 (30.6%) and ECF20 (0.19%). ECF25 is one of the most diverse ECF groups in terms of taxonomic origin of the sequences. Proteins from ECF25 are present mainly in Cyanobaceria (ECF25s1 and ECF25s11, 50%), but also in Firmicutes (11.88%), Deltaproteobacteria (15.84%), Spirochaetes (ECF25s3, 2.97%), Fibrobacteres (ECF25s13, 0.5%), Nitrospirae (ECF25s12, 0.5%), Deinococcus-Thermus (ECF25s5, 6.44%), Chloroflexi (ECF25s17, ECF25s18 and ECF25s19, 6.44%), Gemmatimonadetes (ECF25s4, 1%), Ignavibacteriae (ECF25s9, 1%), Acidobacteria (1%) , Bacteroidetes (1.98%), and Calditrichaeota (0.5%).
Anti-σ factor: Similarly to original ECF25 (Staroń et al., 2009), proteins from ECF25 contain a putative AS factor in position +1, which are mainly single membrane-pass (74.75%). Nevertheless, variants with two or three transmembrane helices are possible. For instance, putative AS factors from Firmicutes order Thermoanaerobacterales (ECF25s14), and Chloroflexi (ECF25s16, ECF25s18, ECF25s19) contain two transmembrane helices, and proteins ECF25s20 contain three transmembrane helices. These putative AS factors typically contain a zinc-binding domain and/or a DUF4384 or a DUF4349.
Genomic context conservation: Other proteins conserved in the genetic neighborhood of ECF25 are a transglycosylase SLT from phages, T2SS, T3SS or T4SS (ECF25s2), a DNA polymerase family A with 5'-3' exonuclease activity involved in DNA repair (ECF25s2), a dephospho-CoA kinase (ECF25s2), a DUF1800 (ECF25s5) and an iron-dependent repressor (ECF25s5).
Studied members: The only member of ECF25 experimentally addressed, SigG from Nostoc punctiforme (ECF25s1) is in charge of the defense against cell wall stress arising from external sources (EDTA, heat, lysozyme, cold) or cellular differentiation (Bell, Lee, & Summers, 2017). SigG is regulated by a single membrane pass AS factor SapG.
Promoter motif conservation: The predicted target promoter motifs of ECF25s1 and ECF25s2 are GGAAC in -35 and GTC in -10. This promoter motif is similar to the original group ECF25 (Rhodius et al., 2013) and the binding motif of SigG in N. punctiforme (Bell et al., 2017).
Summary: ECF25 is regulated by AS factors located in +1 and seem to be involved in cell wall homeostasis.
Number of representative ECFs: 535
Number of non-redundant ECFs: 536
Sequences with C-terminal extension: 0.00%
Sequences with N-terminal extension: 6.16%
Overrepresented phylum: Cyanobacteria [35.70%]
|The third pillar of bacterial signal transduction: classification of the extracytoplasmic function (ECF) sigma factor protein family.||Molecular microbiology||2009||A. Staroń, H. Sofia, S. Dietrich, L. Ulrich, H. Liesegang, T. Mascher||PubMed: 19737356||ECF103, ECF21, ECF123, ECF51, ECF39, ECF281, ECF102, ECF130, ECF122, ECF291, ECF15, ECF242, ECF22, ECF285, ECF106, ECF27, ECF31, ECF240, ECF114, ECF16, ECF38, ECF41, ECF105, ECF116, ECF111, ECF03, ECF239, ECF42, ECF294, ECF17, ECF11, ECF29, ECF235, ECF293, ECF118, ECF265, ECF30, ECF23, ECF14, ECF249, ECF18, ECF115, ECF290, ECF25, ECF121, ECF02, ECF120, ECF289, ECF28, ECF243, ECF19, ECF43, ECF107, ECF12, ECF32, ECF36, ECF292, ECF286, ECF271, ECF26, ECF40, ECF56, ECF33|
|Design of orthogonal genetic switches based on a crosstalk map of σs, anti-σs, and promoters.||Molecular systems biology||2013||V. Rhodius, T. Segall-Shapiro, B. Sharon, A. Ghodasara, E. Orlova, H. Tabakh, D. Burkhardt, K. Clancy, T. Peterson, C. Gross, C. Voigt||PubMed: 24169405||ECF22, ECF27, ECF03, ECF21, ECF39, ECF25, ECF26, ECF42, ECF38, ECF14, ECF29, ECF33, ECF281, ECF290, ECF291|
|Characterization and in vivo regulon determination of an ECF sigma factor and its cognate anti-sigma factor in Nostoc punctiforme.||Molecular microbiology||2017||N. Bell, J. Lee, M. Summers||PubMed: 28105698||ECF25|