The respiratory chain of Pseudomonas pseudoalcaligenes KF707 in membranes isolated from cells grown in the presence or absence of the toxic oxyanion tellurite () was examined. Aerobic growth in the absence of tellurite shows an NADH-dependent respiration which is 80% catalysed by the cytochrome (cyt) bc1-containing pathway leading to two terminal membrane-bound cyt c oxidases inhibited by different concentrations of KCN (IC50 0·2 and 1 μM). A third oxidase, catalysing the remaining 20% of the cyanide-resistant respiration and fully inhibited by 2–3 mM KCN, is also present; this latter pathway accounts for 60–70% of the total NADH-dependent respiration in membranes from cells grown in LB medium supplemented with potassium tellurite (35 μg ml−1). Two high-potential b-type haems (Em,7 +395 and 318 mV) are redox centres of a membrane-bound cyt c oxidase (possibly of the cbb3 type) which shows a 50% decrease of its activity in parallel with a similar decrease of the c-type haem content (mostly soluble cyt c) in membranes from tellurite-grown cells; the latter type of cells specifically contain a cyt b type at +203 mV (pH 9·0) which is likely to be involved in cyanide-resistant respiration. Comparison of the growth curve of KF707 cells in parallel with tellurite uptake showed that intracellular accumulation of tellurium (Te0) crystallites starts from the mid-exponential growth phase, whereas tellurite-induced changes of the respiratory chain are already evident during the early stages of growth. These data were interpreted as showing that reduction of tellurite to tellurium and tellurite-dependent modifications of the respiratory chain are unrelated processes in P. pseudoalcaligenes KF707.
AllenJ. F.,
HolmesN. G.
1986; Electron transport and redox titration. In Photosynthesis. Energy Transduction: a Practical Approach pp 103–141 Edited by
HipkinsM. F.,
BakerN. R.
Oxford: IRL Press;
AvazeriC.,
TurnerR. J.,
PommierJ.,
WeinerJ. H.,
GiordanoG.,
VermeglioA.
1997; Tellurite reductase activity of nitrate reductase is responsible for the basal resistance of Escherichia coli to tellurite. Microbiology 143:1181–1189[CrossRef]
BradfordM. M.
1976; A rapid and sensitive method for quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem 72:248–254[CrossRef]
CunninghamL.,
WilliamsH. D.
1995; Isolation and characterization of mutants defective in the cyanide-insensitive respiratory pathway of Pseudomonas aeruginosa
. J Bacteriol 177:432–438
DaldalF.,
MandaciS.,
WintersteinC.,
MyllykallioH.,
DuyckK.,
ZannoniD.
2001; Mobile cytochrome c 2 and membrane-anchored c y are both efficient electron donors to the cbb 3- and aa 3-type cytochrome c oxidases during respiratory growth of Rhodobacter sphaeroides
. J Bacteriol 183:2013–2024[CrossRef]
HochkoepplerA.,
JenneyF. E.,
LangS. E.,
ZannoniD.,
DaldalF.
1995; Membrane-associated cytochrome c y of Rhodobacter capsulatus is an electron carrier from the cytochrome bc 1 complex to the cytochrome c oxidase during respiration. J Bacteriol 177:608–613
JoblingM. G.,
RitchieD. A.
1988; Genetic and physical analysis of plasmid genes expressing inducible resistance of tellurite in Escherichia coli
. Mol Gen Genet 208:288–293
MooreM. D.,
KaplanS.
1992; Identification of intrinsic high-level resistance to rare-earth oxides and oxyanions in members of the class Proteobacteria : characterization of tellurite, selenite, and rhodium sesquioxide reduction in Rhodobacter sphaeroides
. J Bacteriol 174:1505–1514
MooreM. D.,
KaplanS.
1994; Members of the family Rhodospirillaceae reduce heavy-metal oxyanions to maintain redox poise during photosynthetic growth. ASM News 60:17–24
SchäggerH.,
von JagowG.
1987; Tricine-sodium dodecyl sulfate polyacrylamide gel electrophoresis for the separation of proteins in the range from 1 to 100 kDa. Anal Biochem 166:368–379[CrossRef]
ThomasP. E.,
RyanD.,
LevinD. W.
1976; An improved staining procedure for the detection of the peroxidase activity of cytochrome P-450 on sodium dodecyl sulfate polyacrylamide gels. Anal Biochem 75:168–176[CrossRef]
TrutkoS. M.,
AkimenkoV. K.,
SuzinaN. E.,
AnisimovaL. A.,
ShlyapnikovM. G.,
BaskunovB. P.,
DudaV. I.,
BoroninA. M.
2000; Involvement of the respiratory chain of gram-negative bacteria in the reduction of tellurite. Arch Microbiol 173:178–186[CrossRef]
TurnerR. J.,
WeinerJ. H.,
TaylorD. E.
1992; Use of diethyldithiocarbamate for quantitative determination of tellurite uptake by bacteria. Anal Biochem 204:292–295[CrossRef]
TurnerR. J.,
WeinerJ. H.,
TaylorD. E.
1995; The tellurite-resistance determinants tehAtehB and klaAklaBtelB have different biochemical requirements. Microbiology 141:3133–3140[CrossRef]
ZannoniD.
1995; Aerobic and anaerobic electron transport chains in anoxygenic phototrophic bacteria. In Anoxygenic Photosynthetic Bacteria pp 949–971 Edited by
BlankenshipR. E.,
MadiganM.,
BauerC. E.
Dordrecht: Kluwer;
ZannoniD.,
JasperP.,
MarrsB. L.
1978; Light induced oxygen reduction as a probe of electron transport between respiratory and photosynthetic components in membranes of Rps. capsulata
. Arch Biochem Biophys 191:625–631[CrossRef]
The membrane-bound respiratory chain of Pseudomonas pseudoalcaligenes KF707 cells grown in the presence or absence of potassium telluriteThis work is dedicated to my friend and colleague Franco Tatò, prematurely deceased on 7 July 2001.