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Applied and Environmental Microbiology Dec 2023Many parameters affect phage-bacteria interaction. Some of these parameters depend on the environment in which the bacteria are present. Anaerobiosis effect on phage...
Many parameters affect phage-bacteria interaction. Some of these parameters depend on the environment in which the bacteria are present. Anaerobiosis effect on phage infection in facultative anaerobic bacteria has not yet been studied. The absence of oxygen triggers metabolic changes in facultative bacteria and this affects phage infection and viral life cycle. Understanding how an anaerobic environment can alter the behavior of phages during infection is relevant for the phage therapy success.
Topics: Bacteriophages; Anaerobiosis; Bacteria
PubMed: 37966212
DOI: 10.1128/aem.01491-23 -
Current Biology : CB Mar 2020Oxygen is essential for many organisms who have therefore evolved mechanisms to enable survival during hypoxia. A new study describes how a well-known bacterial...
Oxygen is essential for many organisms who have therefore evolved mechanisms to enable survival during hypoxia. A new study describes how a well-known bacterial surfactant, called surfactin, facilitates bacterial viability when oxygen becomes limiting by reducing oxygen consumption.
Topics: Anaerobiosis; Bacillus subtilis; Microbial Viability; Oxygen; Surface-Active Agents
PubMed: 32208155
DOI: 10.1016/j.cub.2020.01.087 -
Trends in Genetics : TIG Jan 1997
Review
Topics: Adaptation, Physiological; Anaerobiosis; Animals; Biological Evolution; Cell Physiological Phenomena; DNA, Mitochondrial; DNA, Protozoan; Energy Metabolism; Genome; Humans; Kinetoplastida; Models, Biological; Mutation; Organelles; RNA; RNA Editing; RNA, Mitochondrial; Selection, Genetic
PubMed: 9009840
DOI: 10.1016/s0168-9525(96)30116-9 -
Molecular Microbiology May 2008Historically many bacteria have been classified as obligate anaerobes. They have been construed as wholly intolerant of oxygen, a feature that was originally ascribed to...
Historically many bacteria have been classified as obligate anaerobes. They have been construed as wholly intolerant of oxygen, a feature that was originally ascribed to their lack of superoxide dismutases and catalases. Clostridial species were regarded as classic examples. We now know that this view is quite wrong: enzymes that scavenge superoxide, hydrogen peroxide and even oxygen itself abound in anaerobes. In the current issue of Molecular Microbiology, Hillmann et al. demonstrate that full production of these proteins can allow Clostridium acetobutylicum to survive and even grow in oxygenated culture medium. Evidently, oxidative defences in anaerobes can be robust. In all likelihood, they are critical for the movement of bacteria through aerobic environments to new anaerobic habitats.
Topics: Anaerobiosis; Clostridium acetobutylicum; Gene Expression Regulation, Bacterial; Oxidative Stress; Repressor Proteins
PubMed: 18363793
DOI: 10.1111/j.1365-2958.2008.06213.x -
The Quarterly Review of Biology Jun 1990For many animals, the best defense against harsh environmental conditions is an escape to a hypometabolic or dormant state. Facultative metabolic rate depression is the... (Review)
Review
For many animals, the best defense against harsh environmental conditions is an escape to a hypometabolic or dormant state. Facultative metabolic rate depression is the common adaptive strategy of anaerobiosis, hibernation, and estivation, as well as a number of other arrested states. By reducing metabolic rate by a factor ranging from 5 to 100 fold or more, animals gain a comparable extension of survival time that can support months or even years of dormancy. The present review focuses on the molecular control mechanisms that regulate and coordinate cellular metabolism for the transition into dormancy. These include reversible control over the activity state of enzymes via protein phosphorylation or dephosphorylation reactions, pathway regulation via the association or dissociation of particle-bound enzyme complexes, and fructose-2,6-bisphosphate regulation of the use of carbohydrate reserves for biosynthetic purposes. These mechanisms, their interactions, and the regulatory signals (e.g., second messenger molecules, pH) that coordinate them form a common molecular basis for metabolic depression in anoxia-tolerant vertebrates (goldfish, turtles) and invertebrates (marine molluscs), hibernation in small mammals, and estivation in land snails and terrestrial toads.
Topics: Adaptation, Physiological; Anaerobiosis; Animals; Estivation; Glycolysis; Hibernation; Metabolism
PubMed: 2201054
DOI: 10.1086/416717 -
Bioresource Technology Nov 2020
Topics: Anaerobiosis; Bioreactors; Methane; Sewage
PubMed: 32799046
DOI: 10.1016/j.biortech.2020.123955 -
Nutrients Aug 2020Beta-alanine supplementation (BA) has a positive impact on physical performance. However, evidence showing a benefit of this amino acid in aerobic-anaerobic transition... (Meta-Analysis)
Meta-Analysis
Beta-alanine supplementation (BA) has a positive impact on physical performance. However, evidence showing a benefit of this amino acid in aerobic-anaerobic transition zones is scarce and the results controversial. The aim of this systematic review and meta-analysis is to analyze the effects of BA supplementation on physical performance in aerobic-anaerobic transition zones. At the same time, the effect of different dosages and durations of BA supplementation were identified. The search was designed in accordance with the PRISMA guidelines for systematic reviews and meta-analyses and performed in Web of Science (WOS), Scopus, SPORTDiscus, PubMed, and MEDLINE between 2010 and 2020. The methodological quality and risk of bias were evaluated with the Cochrane Collaboration tool. The main variables were the Time Trial Test (TTT) and Time to Exhaustion (TTE) tests, the latter separated into the Limited Time Test (LTT) and Limited Distance Test (LDT). The analysis was carried out with a pooled standardized mean difference (SMD) through Hedges' g test (95% CI). Nineteen studies were included in the systematic review and meta-analysis, revealing a small effect for time in the TTT (SMD, -0.36; 95% CI, -0.87-0.16; I = 59%; = 0.010), a small effect for LTT (SMD, 0.25; 95% CI, -0.01-0.51; I = 0%; = 0.53), and a large effect for LDT (SMD, 4.27; 95% CI, -0.25-8.79; I = 94%; = 0.00001). BA supplementation showed small effects on physical performance in aerobic-anaerobic transition zones. Evidence on acute supplementation is scarce (one study); therefore, exploration of acute supplementation with different dosages and formats on physical performance in aerobic-anaerobic transition zones is needed.
Topics: Aerobiosis; Anaerobiosis; Dietary Supplements; Humans; Physical Functional Performance; Sports Nutritional Physiological Phenomena; beta-Alanine
PubMed: 32824885
DOI: 10.3390/nu12092490 -
The Australian Journal of Experimental... Feb 1955
Topics: Anaerobiosis; Animals; Bacteria; Iron; Wool
PubMed: 14389171
DOI: 10.1038/icb.1955.4 -
Viruses Sep 2020Since the discovery of phages in 1915, these viruses have been studied mostly in aerobic systems, or without considering the availability of oxygen as a variable that... (Review)
Review
Since the discovery of phages in 1915, these viruses have been studied mostly in aerobic systems, or without considering the availability of oxygen as a variable that may affect the interaction between the virus and its host. However, with such great abundance of anaerobic environments on the planet, the effect that a lack of oxygen can have on the phage-bacteria relationship is an important consideration. There are few studies on obligate anaerobes that investigate the role of anoxia in causing infection. In the case of facultative anaerobes, it is a well-known fact that their shifting from an aerobic environment to an anaerobic one involves metabolic changes in the bacteria. As the phage infection process depends on the metabolic state of the host bacteria, these changes are also expected to affect the phage infection cycle. This review summarizes the available information on phages active on facultative and obligate anaerobes and discusses how anaerobiosis can be an important parameter in phage infection, especially among facultative anaerobes.
Topics: Anaerobiosis; Bacteria; Bacteriophages; Host Microbial Interactions; Oxygen; Virus Replication
PubMed: 32993161
DOI: 10.3390/v12101091 -
Archives of Biochemistry and Biophysics Apr 2021The discovery of a new energy-coupling mechanism termed flavin-based electron bifurcation (FBEB) in 2008 revealed a novel field of application for flavins in biology.... (Review)
Review
The discovery of a new energy-coupling mechanism termed flavin-based electron bifurcation (FBEB) in 2008 revealed a novel field of application for flavins in biology. The key component is the bifurcating flavin endowed with strongly inverted one-electron reduction potentials (FAD/FAD• ≪ FAD•/FADH) that cooperatively transfers in its reduced state one low and one high-energy electron into different directions and thereby drives an endergonic with an exergonic reduction reaction. As energy splitting at the bifurcating flavin apparently implicates one-electron chemistry, the FBEB machinery has to incorporate prior to and behind the central bifurcating flavin 2e-to-1e and 1e-to-2e switches, frequently also flavins, for oxidizing variable medium-potential two-electron donating substrates and for reducing high-potential two-electron accepting substrates. The one-electron carriers ferredoxin or flavodoxin serve as low-potential (high-energy) electron acceptors, which power endergonic processes almost exclusively in obligate anaerobic microorganisms to increase the efficiency of their energy metabolism. In this review, we outline the global organization of FBEB enzymes, the functions of the flavins therein and the surrounding of the isoalloxazine rings by which their reduction potentials are specifically adjusted in a finely tuned energy landscape.
Topics: Anaerobiosis; Electron Transport; Electrons; Energy Metabolism; Flavin-Adenine Dinucleotide; Flavodoxin
PubMed: 33609536
DOI: 10.1016/j.abb.2021.108796