Table 12. ECF  factors and their regulons in various bacteria

Organism
/ ECF  / Known Stimuli / Regulon / Proposed function / Regulation / References
Stress Responses
B. subtilis / W / antimicrobial compounds that inhibit cell wall synthesis; alkali pH / ~50 proteins / Detoxification, antibiosis / RsiW (anti-) / (Cao et al., 2001; Huang et al., 1999; Turner and Helmann, 2000)
B. subtilis / M / salt stress / survival in high concentrations of salt / YhdL-YhdK (anti-) / (Horsburgh and Moir, 1999)
Bartonella henselae / E / heat shock / HtrA / (Resto-Ruiz et al., 2000)
E. coli / E / misfolded proteins in periplasm; extreme heat shock / ~20 proteins / folding of proteins in periplasm / RseA-RseB (anti-) / (Danese and Silhavy, 1997; Dartigalongue et al., 2001; De Las Penas et al., 1997a; 1997b; Missiakas et al., 1997)
M. tuberculosis / E / heat shock, acidic pH, detergent, oxidative stress / (Wu et al., 1997)
M. tuberculosis / H / heat shock; disulfide stress, organic peroxides / respond to heat shock and / (Fernandes et al., 1999)
P. fluorescens LS107d2 / PrtI / temperatures above 25OC / AprX (protease) / protease production / PrtR (anti-) / (Burger et al., 2000)
S. coelicolor / R / disulfide stress / ~28 proteins (TrxB, TrxA, HrdD, et) / maintains intracellular reducing environment / RsrA (anti-) / (Kang et al., 1999; Paget et al., 2001; 1998)
Vibrio angustum / E / high temperature / (Hild et al., 2000)
Metal Transport
B. bronchiseptica / BupI / siderophore / BfrZ (siderophore receptor) / iron uptake / BupR (anti-) / (Pradel and Locht, 2001)
E. coli / FecI / Iron starvation; ferric-citrate / FecA, B, C, D, E / ferric citrate transport / FecR (anti-) / (Angerer et al., 1995; Ochs et al., 1996)
P. aeruginosa / PvdS / iron starvation / RegA, PvdA, PvdD, PvdE, PvcA,B,C,D, PtxR, ToxA and PrpL / regulates biosynthesis of pyoverdine, exotoxin A and PrpL (extracellular proteinase) / Repressed by Fur in iron-rich media / (Leoni et al., 2000; Wilson and Lamont, 2000; Wilson et al., 2001)
P. fluorescens M114 / PbrA / Iron starvation / PbuA (receptor), a casein protease / Iron uptake / Repressed by Fur in iron-rich media / (Sexton et al., 1995; Sexton et al., 1996)
Rhizobium leguminosarum / RpoI / Regulates siderophore production / (Yeoman et al., 1999)
Ralstonia eutropha CH34 / CnrH / Nickel, cobalt / CnrY, CnrX, CnrH, CnrC, CnrB, CnrA / Cobalt and nickel resistance / (Tibazarwa et al., 2000)
Virulence-related
Azotobacter vinelandii / AlgU / AlgD / regulate alginate production and cysts formation / repressed by MucA, MucC (anti-) / (Martinez-Salazar et al., 1996; Moreno et al., 1998; Nunez et al., 2000)
P. aeruginosa / E / AlgD / alginate production and tolerance to environmental stress / MucA-MucB / (Hershberger et al., 1995; Mathee et al., 1997; Rowen and Deretic, 2000; Xie et al., 1996)
P. syringae / AlgT / Heat, osmotic stress, H2O2, paraquat, and copper sulfate / AlgD / alginate production and tolerance to environmental stress / (Keith and Bender, 1999)
Salmonella typhimurium / E / HtrA, FkpA / Virulence and immunogenicity / RseA-RseB (possible anti-) / (Humphreys et al., 1999)
Erwinia amylovora Ea321 / HrpL / Nutrition (carbon, nitrogen), pH, temperature / HrpN, HrpI / hypersensitive response, pathogenesis / HrpS / (Wei and Beer, 1995)
P. syringae / HrpL / Nutrition (carbon, nitrogen), pH, osmotic stress / Hrp proteins, HrmA / Hypersensitive response, pathogenesis / Activated by HrpR-HrpS / (Xiao et al., 1994)
Cell surface-related
B. subtilis / X / cell density signals, and antimicrobial compounds / >10 proteins / Modification of cell envelope / RsiX (anti-) / (Huang et al., 1997; Huang and Helmann, 1998; Turner and Helmann, 2000)
S. coelicolor / E / cell wall active antibiotics; lysozyme / HrdD / requiredfor normal cell wall structure / CseB-CseC / (Paget et al., 1999a; Paget et al., 1999b)
P. aeruginosa and
P. fluorescens / X / OprF / Regulate the expression of major outer membrane protein / (Brinkman et al., 1999)
Photobacterium species strain SS9 / E / Cold temperature and high pressure / Controls outer membrane protein synthesis / (Chi and Bartlett, 1995)
M. xanthus / RpoE1 / motility / (Ward et al., 1998)
Xanthomonas campestris / RfaY / Lipopolysaccharide biosynthnesis / (Dow et al., 1995)
Developmental and mophological changes
Caulobacter crescentus / T, U / G1-S phase transition / Regulates early S-phase gene expression / Repressed by CtrA / (Laub et al., 2000)
S. coelicolor A3(2) / BldN / BldM / Aerial mycelium formation / Regulated by BldG, H / (Bibb et al., 2000)
S. griseus / AdsA / A-factor
(-butyrolactone) / Aerial hyphae formation / Activated by AdpA / (Yamazaki et al., 2000)
Others
M. xanthus / CarQ / light / CarC, CarS / Regulation of carotenoid biosynthesis / CarR (anti-) / (Gorham et al., 1996; Martinez-Argudo et al., 1998)
Rhodobacter sphaeroides / E / a signal from tetrapyrrole biosynthesis / CycA / Regulation of cytochrome c2 biosynthesis / ChrR (anti-) / (Newman et al., 1999)
S. antibioticus / E / Actinomycin production / (Jones et al., 1997)
Starkeya novella / E / SorAB / thiosulfate oxidation / (Kappler et al., 2001)