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Medecine Sciences : M/S Dec 2018
Topics: Aerobiosis; Animals; Carcinoma, Hepatocellular; Cell Transformation, Neoplastic; Fermentation; Glycolysis; Humans; Liver Neoplasms; Mice; Oxygen Consumption; Tumor Hypoxia
PubMed: 30623768
DOI: 10.1051/medsci/2018303 -
Journal of Bacteriology Apr 1983The role of protein induction and repression in the adaptation of Escherichia coli to changes in the supply of oxygen and other electron acceptors is only poorly...
The role of protein induction and repression in the adaptation of Escherichia coli to changes in the supply of oxygen and other electron acceptors is only poorly understood. We have studied the changes in cellular protein composition associated with this adaptation by measuring the levels of 170 individual polypeptides produced during aerobic or anaerobic growth of E. coli, with and without nitrate. Nineteen polypeptides had levels highest during aerobic growth. These proteins include the enzymes of the pyruvate dehydrogenase complex, several tricarboxylic acid cycle enzymes, superoxide dismutase, and tetrahydropteroyltriglutamate transmethylase. The other aerobiosis-induced proteins have not been identified. These polypeptides are major cellular proteins during aerobic growth and display several different patterns of regulation in response to medium composition. Induction ratios for oxygen ranged from 2.2 to 11.2, with one exceptional member, superoxide dismutase, increasing 71-fold with aeration. Most of the proteins were also induced by nitrate during anaerobic growth. The time course of induction after shifts in oxygen supply revealed similarities in response among proteins of related function or metabolic regulation class. These results are discussed in relation to previously reported information on the identified aerobiosis-induced proteins.
Topics: Aerobiosis; Bacterial Proteins; Escherichia coli; Time Factors
PubMed: 6339477
DOI: 10.1128/jb.154.1.344-350.1983 -
Environmental Science and Pollution... Oct 2023Chloroethenes are globally prevalent groundwater contaminants. Since 2014, TCE has been shown to be degradable in an aerobic metabolic process where it is used as sole...
Chloroethenes are globally prevalent groundwater contaminants. Since 2014, TCE has been shown to be degradable in an aerobic metabolic process where it is used as sole energy source and growth substrate by a mixed bacteria culture (SF culture). In 2019, the SF culture was shown to be successfully used in bioaugmentation approaches under field-relevant conditions. In this study, a combined bio-/electro-approach to stimulate the TCE degradation by the SF culture was investigated in laboratory experiments. Column experiments were set up to compare a bioaugmentation approach with an electrochemical biostimulated bioaugmentation approach. Low strength direct current increased the amount of degraded TCE to about 150 % of the control. Through lowering the inflow concentration of oxygen, the effect of the electro-biostimulation in a low oxygen setting confirmed the potential of the bio-electro process for treatment of oxygen-deprived, TCE-contaminated sites.
Topics: Biodegradation, Environmental; Water Pollutants, Chemical; Aerobiosis; Groundwater; Oxygen
PubMed: 37735338
DOI: 10.1007/s11356-023-29839-1 -
Microbiological Reviews Sep 1996Our review of the metabolic pathways of pyridines and aza-arenes showed that biodegradation of heterocyclic aromatic compounds occurs under both aerobic and anaerobic... (Review)
Review
Our review of the metabolic pathways of pyridines and aza-arenes showed that biodegradation of heterocyclic aromatic compounds occurs under both aerobic and anaerobic conditions. Depending upon the environmental conditions, different types of bacteria, fungi, and enzymes are involved in the degradation process of these compounds. Our review indicated that different organisms are using different pathways to biotransform a substrate. Our review also showed that the transformation rate of the pyridine derivatives is dependent on the substituents. For example, pyridine carboxylic acids have the highest transformation rate followed by mono-hydroxypyridines, methylpyridines, aminopyridines, and halogenated pyridines. Through the isolation of metabolites, it was possible to demonstrate the mineralization pathway of various heterocyclic aromatic compounds. By using 14C-labeled substrates, it was possible to show that ring fission of a specific heterocyclic compound occurs at a specific position of the ring. Furthermore, many researchers have been able to isolate and characterize the microorganisms or even the enzymes involved in the transformation of these compounds or their derivatives. In studies involving 18O labeling as well as the use of cofactors and coenzymes, it was possible to prove that specific enzymes (e.g., mono- or dioxygenases) are involved in a particular degradation step. By using H2 18O, it could be shown that in certain transformation reactions, the oxygen was derived from water and that therefore these reactions might also occur under anaerobic conditions.
Topics: Acridines; Aerobiosis; Anaerobiosis; Bacteria; Biodegradation, Environmental; Fungi; Pyridines; Quinolines
PubMed: 8840783
DOI: 10.1128/mr.60.3.483-498.1996 -
American Journal of Physiology.... Dec 2017Muscle contraction requires the physiology to adapt rapidly to meet the surge in energy demand. To investigate the shift in metabolic control, especially between oxygen...
Muscle contraction requires the physiology to adapt rapidly to meet the surge in energy demand. To investigate the shift in metabolic control, especially between oxygen and metabolism, researchers often depend on near-infrared spectroscopy (NIRS) to measure noninvasively the tissue O Because NIRS detects the overlapping myoglobin (Mb) and hemoglobin (Hb) signals in muscle, interpreting the data as an index of cellular or vascular O requires deconvoluting the relative contribution. Currently, many in the NIRS field ascribe the signal to Hb. In contrast, H NMR has only detected the Mb signal in contracting muscle, and comparative NIRS and NMR experiments indicate a predominant Mb contribution. The present study has examined the question of the NIRS signal origin by measuring simultaneously the H NMR, P NMR, and NIRS signals in finger flexor muscles during the transition from rest to contraction, recovery, ischemia, and reperfusion. The experiment results confirm a predominant Mb contribution to the NIRS signal from muscle. Given the NMR and NIRS corroborated changes in the intracellular O, the analysis shows that at the onset of muscle contraction, O declines immediately and reaches new steady states as contraction intensity rises. Moreover, lactate formation increases even under quite aerobic condition.
Topics: Adult; Aerobiosis; Energy Metabolism; Ergometry; Exercise; Fingers; Hemoglobins; Humans; Ischemia; Magnetic Resonance Spectroscopy; Male; Muscle Contraction; Muscle, Skeletal; Myoglobin; Oxygen; Oxygen Consumption; Regional Blood Flow; Spectroscopy, Near-Infrared
PubMed: 28877871
DOI: 10.1152/ajpregu.00203.2017 -
Scientific Reports Apr 2020The present study aimed to evaluate the chemical composition, profile and fermentative losses, microbial population and the aerobic stability of mixed silages of cactus...
The present study aimed to evaluate the chemical composition, profile and fermentative losses, microbial population and the aerobic stability of mixed silages of cactus pear and gliricidia. The treatments corresponded to the addition levels of gliricidia (Gliricidia sepium (Jacq.) Steud), in the silages of cactus pear (Opuntia ficus indica Mill.), at ratios 0%, 25%, 50%, 75% and 100% gliricidia. The data were subjected to analysis of variance and regression to evaluate the effect of the addition levels of gliricidia. The average related to the opening days were compared by the Tukey's test and the average hours of exposure to air were compared by the Student's t-test. The addition of gliricidia in cactus pear silage provided a linear increasing effect for pH, crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL), neutral detergent insoluble protein (NDIP), and increased aerobic stability (AS). The highest dry matter recovery was estimated in the silages with 58% gliricidia. Based on the fermentative, chemical composition and silage losses, all the silages tested were adequate. However, considering aerobic stability, the addition of at least 25% gliricidia is recommended to provide the animal a feed with important quality and high nutritional value.
Topics: Aerobiosis; Fabaceae; Microbial Consortia; Opuntia; Silage
PubMed: 32321984
DOI: 10.1038/s41598-020-63905-9 -
Genome Biology 2009The growth-rate of an organism is an important phenotypic trait, directly affecting its ability to survive in a given environment. Here we present the first large scale...
BACKGROUND
The growth-rate of an organism is an important phenotypic trait, directly affecting its ability to survive in a given environment. Here we present the first large scale computational study of the association between ecological strategies and growth rate across 113 bacterial species, occupying a variety of metabolic habitats. Genomic data are used to reconstruct the species' metabolic networks and habitable metabolic environments. These reconstructions are then used to investigate the typical ecological strategies taken by organisms in terms of two basic species-specific measures: metabolic variability--the ability of a species to survive in a variety of different environments; and co-habitation score vector--the distribution of other species that co-inhabit each environment.
RESULTS
We find that growth rate is significantly correlated with metabolic variability and the level of co-habitation (that is, competition) encountered by an organism. Most bacterial organisms adopt one of two main ecological strategies: a specialized niche with little co-habitation, associated with a typically slow rate of growth; or ecological diversity with intense co-habitation, associated with a typically fast rate of growth.
CONCLUSIONS
The pattern observed suggests a universal principle where metabolic flexibility is associated with a need to grow fast, possibly in the face of competition. This new ability to produce a quantitative description of the growth rate-metabolism-community relationship lays a computational foundation for the study of a variety of aspects of the communal metabolic life.
Topics: Aerobiosis; Bacteria; Ecosystem; Genome, Bacterial; Metabolic Networks and Pathways; Models, Biological; Time Factors
PubMed: 19500338
DOI: 10.1186/gb-2009-10-6-r61 -
Scientific Reports Aug 2019Anemia defined as reduced hemoglobin levels of red blood cells may carry less oxygen to skeletal muscle and impair physical performance. Previous studies have...
Anemia defined as reduced hemoglobin levels of red blood cells may carry less oxygen to skeletal muscle and impair physical performance. Previous studies have shown that exercise intolerance was related to moderate or severe anemia, however, the relationship to mild anemia was unknown. We investigated the cross-sectional association of mild anemia defined as a hemoglobin level of 10.0-13.9 g/dL with physical fitness in 3,666 military young males in Taiwan in 2014. Aerobic fitness was evaluated by 3000-meter run test, and anaerobic fitness was evaluated by 2-minute sit-ups and 2-minute push-ups, respectively. Multiple logistic regressions for the best 10% and the worst 10% performers were used to determine the relationship. There were 343 mild anemic males in whom 47.8% were microcytic anemia and 3,323 non-anemic males for the analysis. The multiple logistic regression shows that as compared with non-anemic males, mild anemic males were more likely to be the worst 10% performers in the 3000-meter run test (odds ratios (OR) and 95% confidence intervals: 1.47, 1.01-2.14) after adjusting for age, service specialty, body mass index, waist size, mean blood pressure, unhealthy behaviors, lipid profiles, and exercise frequency. On the contrary, mild anemic males had higher possibility to be the best 10% performers in the 2-minute push-ups test (OR: 1.48, 1.08-2.04). However, there was no association between mild anemia and 2-minute sit-ups. Our findings suggest that unspecified mild anemia might be associated with lower cardiorespiratory fitness but not with anaerobic fitness in physically active military males.
Topics: Aerobiosis; Anaerobiosis; Anemia; Cardiorespiratory Fitness; Cross-Sectional Studies; Exercise; Humans; Male; Military Personnel; Physical Fitness; Taiwan; Young Adult
PubMed: 31371766
DOI: 10.1038/s41598-019-47625-3 -
Open Biology Oct 2012Alternative splicing of the pyruvate kinase M gene involves a choice between mutually exclusive exons 9 and 10. Use of exon 10 to generate the M2 isoform is crucial for...
Alternative splicing of the pyruvate kinase M gene involves a choice between mutually exclusive exons 9 and 10. Use of exon 10 to generate the M2 isoform is crucial for aerobic glycolysis (the Warburg effect) and tumour growth. We previously demonstrated that splicing enhancer elements that activate exon 10 are mainly found in exon 10 itself, and deleting or mutating these elements increases the inclusion of exon 9 in cancer cells. To systematically search for new enhancer elements in exon 10 and develop an effective pharmacological method to force a switch from PK-M2 to PK-M1, we carried out an antisense oligonucleotide (ASO) screen. We found potent ASOs that target a novel enhancer in exon 10 and strongly switch the splicing of endogenous PK-M transcripts to include exon 9. We further show that the ASO-mediated switch in alternative splicing leads to apoptosis in glioblastoma cell lines, and this is caused by the downregulation of PK-M2, and not by the upregulation of PK-M1. These data highlight the potential of ASO-mediated inhibition of PK-M2 splicing as therapy for cancer.
Topics: Aerobiosis; Alternative Splicing; Cell Line, Tumor; Enhancer Elements, Genetic; Exons; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Neoplastic; Glycolysis; HEK293 Cells; Humans; Isoenzymes; Neoplasm Proteins; Neoplasms; Oligonucleotides, Antisense; Pyruvate Kinase
PubMed: 23155487
DOI: 10.1098/rsob.120133 -
BioMed Research International 2013Propionibacterium acnes is one of the dominant commensals on the human skin and also an opportunistic pathogen in relation to acne, sarcoidosis, prostate cancer, and... (Comparative Study)
Comparative Study
Correlation between phylogroups and intracellular proteomes of Propionibacterium acnes and differences in the protein expression profiles between anaerobically and aerobically grown cells.
Propionibacterium acnes is one of the dominant commensals on the human skin and also an opportunistic pathogen in relation to acne, sarcoidosis, prostate cancer, and various infections. Recent investigations using housekeeping and virulence genes have revealed that the species consists of three major evolutionary clades (types I, II, and III). In order to investigate protein expression differences between these phylogroups, proteomic profiles of 21 strains of P. acnes were investigated. The proteins extracted from cells cultured under anaerobic and aerobic conditions were analysed using a SELDI-TOF mass spectrometer, high-resolution capillary gel electrophoresis, and LC-MS/ MS. The SELDI spectral profiles were visualised as a heat map and a dendrogram, which resulted in four proteomic groups. Strains belonging to type I were represented in the proteome Group A, while Group B contained type III strains. Groups C and D contained mixtures of types I and II. Each of these groups was not influenced by differences in culture conditions. Under anoxic growth conditions, a type IB strain yielded high expressions of some proteins, such as methylmalonyl-CoA epimerase and the Christie-Atkins-Munch-Petersen (CAMP) factor. The present study revealed good congruence between genomic and proteomic data suggesting that the microenvironment of each subtype may influence protein expression.
Topics: Aerobiosis; Anaerobiosis; Bacterial Proteins; Gene Expression Regulation, Bacterial; Oxygen; Propionibacterium acnes; Proteome
PubMed: 23878795
DOI: 10.1155/2013/151797