Role of proton motive force in phototactic and aerotactic responses of Rhodopseudomonas sphaeroides

Journal Article · Fri Mar 01 04:00:00 EST 1985 · J. Bacteriol.; (United States)

OSTI ID:5558726

Armitage, J P; Ingham, C; Evans, M C.W.

Rhodopseudomonas sphaeroides grown under nonrigorous anaerobic conditions in the light developed components of a branched respiratory electron transfer chain, and a photosynthetic electron transfer chain. Both respiratory pathways were sensitive to rotenone and high concentrations of cyanide, but oxygen uptake was only partially inhibited by the addition of low concentrations of cyanide or antimycin A. When incubated anaerobically in the dark, R. sphaeroides responded positively to an oxygen gradient in the absence of rotenone. In the presence of rotenone, aerotaxis only occurred when the antimycin A-sensitive branch of the pathway was functioning, although both branches still reduced oxygen. Although there was electron movement along the respiratory chain, aerotaxis only occurred in response to a change in proton motive force. When incubated anaerobically in the light, the movement of R. sphaeroides up to a light gradient depended on photosynthetic electron transport. When incubated aerobically, high-intensity actinic illumination inhibited oxygen uptake and aerotaxis. In a low-intensity light gradient the phototactic response was inhibited by oxygen. These results are discussed in relation to the interaction of the electron transfer chains and their roles in controlling tactic responses in R. sphaeroides.

• Research Organization: Univ. College of London, England
• OSTI ID: 5558726
• Journal Information: J. Bacteriol.; (United States), Journal Name: J. Bacteriol.; (United States) Vol. 161:3; ISSN JOBAA
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140505 -- Solar Energy Conversion-- Photochemical
Photobiological
& Thermochemical Conversion-- (1980-)
550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
AEROBIC CONDITIONS
ANAEROBIC CONDITIONS
BACTERIA
BARYONS
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL PATHWAYS
CHEMICAL REACTIONS
CYANIDES
ELECTRON TRANSFER
ELEMENTARY PARTICLES
ELEMENTS
FERMIONS
GROWTH
HADRONS
KINETICS
MICROORGANISMS
NONMETALS
NUCLEONS
OXYGEN
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PROTONS
REACTION KINETICS
RESPIRATION
RHODOPSEUDOMONAS
SYNTHESIS