PMID: 23387095Feb 2, 1990

Comparison of the contribution from different energy-linked reactions to the function of a membrane potential in photosynthetic bacteria

Biochimica Et Biophysica Acta
B F NoreM Baltscheffsky


The steady-state membrane potentials generated by light, PP(i), ATP or the reverse transhydrogenase reaction were studied in chromatophores from two different phototrophic bacteria, Rhodospirillum rubrum and Rhodopseudomonas viridis. The membrane potentials generated by the different energy-linked reactions were evaluated by a tetraphenylboron(TPB(-)) ion-selective electrode. The generated by light was estimated to be 110 mV and 50 mV in R. rubrum and Rps. viridis chromatophores, respectively. In the dark, PP (i), ATP and reversed transhydrogenase generated membrane potentials in R. rubrum and Rps. viridis chromatophores 50, 60 and 35 mV, and 14, 35 and 25 mV,respectively. The effect of magnesium ion on the membrane potential generated by different energy-linked reactions was also studied. The induced by different energy-generating reactions in R. rubrum and Rps. viridis chromatophores and the possible relationship to the chromatophore structures are discussed.

Related Concepts

Resting Potentials
Proton-translocating pyrophosphatase
Rhabdoderma rubrum
Ion-Selective Electrodes
Ribes rubrum
DNA-dependent ATPase
Magnesium Ions

Trending Feeds


Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Synapse Loss as Therapeutic Target in MS

As we age, the number of synapses present in the human brain starts to decline, but in neurodegenerative diseases this occurs at an accelerated rate. In MS, it has been shown that there is a reduction in synaptic density, which presents a potential target for treatment. Here is the latest research on synapse loss as a therapeutic target in MS.

Artificial Intelligence in Cardiac Imaging

Artificial intelligence (ai) techniques are increasingly applied to cardiovascular (cv) medicine in cardiac imaging analysis. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

Social Learning

Social learning involves learning new behaviors through observation, imitation and modeling. Follow this feed to stay up to date on the latest research.

Cell Atlas of the Human Eye

Constructing a cell atlas of the human eye will require transcriptomic and histologic analysis over the lifespan. This understanding will aid in the study of development and disease. Find the latest research pertaining to the Cell Atlas of the Human Eye here.

Single Cell Chromatin Profiling

Techniques like ATAC-seq and CUT&Tag have the potential to allow single cell profiling of chromatin accessibility, histones, and TFs. This will provide novel insight into cellular heterogeneity and cell states. Discover the latest research on single cell chromatin profiling here.

Genetic Screens in iPSC-derived Brain Cells

Genetic screening is a critical tool that can be employed to define and understand gene function and interaction. This feed focuses on genetic screens conducted using induced pluripotent stem cell (iPSC)-derived brain cells.