[Effect of the redox potential on the growth of aerobic microorganisms].

E A Andreeva; I L Rabotnova

PubMed · 30023

[Effect of the redox potential on the growth of aerobic microorganisms].

Abstract

The effect of redox potential was studied on the growth of the following aerobic microorganisms: Candida utilis, Bacillus megaterium, Pseudomonas fluorescens. The action of oxidizing agents (K3Fe(CN)6, KIO3, K2Cr207 and KMnO4) and reducing agents (ascorbic acid, sodium thioglycolate, K4Fe (CN)6 and Na2S2O3) on the growth rate was investigated. K3Fe(CN)6, ascorbic acid, sodium thioglycolate and K4Fe(CN)6 were found to be suitable for buffering the Eh of the medium. The potential could be shifted by 50--200 mV by adding various reducing and oxidizing agents. The rate of growth of C. utilis, Bac. megaterium and Ps. fluorescens did not depend on the potential value.

Explore related subjects

Aerobiosis Bacillus megaterium Candida Culture Media Hydrogen-Ion Concentration Oxidation-Reduction Oxygen Consumption Pseudomonas fluorescens Time Factors Journal Article

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

E A Andreeva, I L Rabotnova. [Effect of the redox potential on the growth of aerobic microorganisms].. https://pubmed.ncbi.nlm.nih.gov/30023/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed1979

Use of lac operon fusions to isolate Escherichia coli mutants with altered expression of the fumarate reductase system in response to substrate and respiratory controls.

Explore the source record for details and available documents.

Aerobiosis↗

PubMed1979

Aerobic lactate synthesis by cardiac muscle.

Cardiac lactate production under aerobic conditions is absolutely dependent upon the availability of extracellular pyruvate. In the steady state, aerobic lactate output is largely independent of cardiac work load, but increases slightly when octanoate is included in addition to pyruvate in the perfusion fluid. Transient episodes of supra-normal lactate production are seen after sudden increases in cardiac work output, and also after transitions from octanoate to pyruvate in the perfusion media. These pulses of lactate production are invariably associated with the slow activation of pyruvate dehydrogenase in response to a sudden change in cardiac metabolic state, and they are abolished by pre-perfusion with dichloracetate, which converts pyruvate dehydrogenase into the fully active form. A second, additional component of the lactate pulses is sensitive to pre-perfusion with the transaminase inhibitor aminooxyacetate. The size of the second component is markedly dependent upon the precise protocol adopted for the experiment, and these variations suggest that the second component is associated with a major redistribution of cardiac Krebs' cycle intermediates and amino acids following the initial exposure to pyruvate-containing media. Steadystate aerobic lactate production is insensitive to both dichloroacetate and aminooxyacetate, and is thought to result from a direct exchange of malate for oxaloacetate across the heart mitochondrial membranes.

Aerobiosis↗

PubMed1979

Effects of inhibitory ligands on the aerobic carbon monoxide complex of cytochrome c oxidase.

1. In the presence of both CO and O2, ox heart cytochrome c oxidase forms a 607 nm-peak intermediate distinct from both the cytochrome a2+a3 2+CO and the cytochrome a3+a3 2+CO ('mixed-valence') CO complexes. 2. This aerobic CO compound is stable towards ferricyanide addition, but decomposed on treatment with ferric cytochrome a2 ligands such as formate, cyanide and azide. 3. Addition of formate or cyanves rise to a complex with alpha-peak at 598 nm, not identical with any azide complex of the free enzyme, but possibly a cytochrome a3 2+NO complex produced by oxidative attack of partially reduced O2 on the azide. 4. The results support the idea that although the initial reaction of oxygen is with cytochrome a3 2+, the next step is not an oxidation of the ferrous cytochrome a3, but a transfer of O2 to a neighbouring group, such as Cu+, to give Cu2+O2- or similar complexes. 5. The aerobic CO complex is then identified as a3+a3 2+COCu2+O2-; a similar compound ('Compound C') is formed by photolysis of a3+a3 2+CO (the 'mixed-valence' CO complex) in the presence of oxygen at low temperatures.

Aerobiosis↗