Microbial Metal Respiration
Title | Microbial Metal Respiration PDF eBook |
Author | Johannes Gescher |
Publisher | Springer Science & Business Media |
Pages | 237 |
Release | 2014-02-21 |
Genre | Science |
ISBN | 3642328679 |
Microbes can respire on metals. This seemingly simple finding is one of the major discoveries that were made in the field of microbiology in the last few decades. The importance of this observation is evident. Metals are highly abundant on our planet. Iron is even the most abundant element on Earth and the forth most abundant element in the Earth’s crust. Hence, in some environments iron, but also other metals or metalloids, are the dominant respiratory electron acceptors. Their reduction massively drives the carbon cycle in these environments and establishes redox cycles of the metallic electron acceptors themselves. These redox cycles are not only a driving force for other biotic reactions but are furthermore necessary for initiating a number of geochemically relevant abiotic redox conversions. Although widespread and ecologically influential, electron transfer onto metals like ferric iron or manganese is biochemically challenging. The challenge is to transfer respiratory electrons onto metals that occur in nature at neutral pH in the form of metal oxides or oxihydroxides that are effectively insoluble. Obviously, it is necessary that the microbes specially adapt in order to catalyze the electron transfer onto insoluble electron acceptors. The elucidation of these adaptations is an exciting ongoing process. To sum it up, dissimilatory metal reduction has wide-spread implications in the field of microbiology, biochemistry and geochemistry and its discovery was one of the major reasons to establish a novel scientific field called geomicrobiology. Recently, the discovery of potential applications of dissimilatory metal reducers in bioremediation or current production in a microbial fuel cell further increased the interest in studying microbial metal reduction.
New Insights Into the Mechanism of Bacterial Metal Respiration
Title | New Insights Into the Mechanism of Bacterial Metal Respiration PDF eBook |
Author | Thomas J. DiChristina |
Publisher | |
Pages | |
Release | 2004 |
Genre | |
ISBN |
This project goal is to identify genes and gene products required for microbial metal reduction: reductive dissolution of iron; reductive dissolution of manganese; reductive precipitation of selenium; reductive precipitation of uranium; and reductive precipitation of technetium.
Molecular Mechanisms of Microbial Iron Respiration by Shewanella Oneidensis MR-1
Title | Molecular Mechanisms of Microbial Iron Respiration by Shewanella Oneidensis MR-1 PDF eBook |
Author | Justin Lee Burns |
Publisher | |
Pages | |
Release | 2010 |
Genre | Microbial respiration |
ISBN |
Metal-respiring bacteria occupy a central position in a variety of environmentally important processes including the biogeochemical cycling of metals and carbon, biocorrosion of steel surfaces, bioremediation of radionuclide-contaminated aquifers, and electricity generation in microbial fuel cells. Metal-respiring bacteria are presented, however, with a unique physiological challenge: they are required to respire anaerobically on electron acceptors (e.g., Fe(III) oxides, elemental sulfur) that are highly insoluble at circumneutral pH and unable to enter the cell and contact inner membrane-localized respiratory systems. To overcome these physiological problems, metal-respiring bacteria are postulated to employ a variety of novel respiratory strategies not found in other bacteria, including 1) direct enzymatic reduction at the cell surface, 2) electron shuttling between the cell and metal surfaces, and 3) metal solubilization by bacterially-produced organic ligands followed by respiration of the soluble organic-metal complexes. This work highlights my latest findings on the genetic and enzymatic mechanism of metal respiration by Shewanella oneidensis, a facultative anaerobe ubiquitous to redox-stratified natural waters and sediments.
Bacteria-Metal Interactions
Title | Bacteria-Metal Interactions PDF eBook |
Author | Daad Saffarini |
Publisher | Springer |
Pages | 92 |
Release | 2015-05-20 |
Genre | Science |
ISBN | 3319185705 |
This book provides a detailed description and analysis of the reduction and metabolism of metals and metalloids by sulfate reducing bacteria. The molecular mechanisms of bacterial resistance to copper are examined as well as extracellular electron transfer and bacterial metal oxide respiration. Furthermore, in this book enrichment, isolation, and physiology of magnetotactic bacteria are discussed. The interactions of bacteria with metals in natural environments and their role in metal cycling have been studied for decades. Advances in studies of bacteria-metal interactions identified numerous important aspects of these interactions, such as bioremediation of metal-contaminated environments, the role of metals in redox reactions and other cellular functions, as well as the role of metals in toxicity and infection. Microbiologists, environmental scientists, and students interested in microbe interactions with metals and their effect on the environment and their application in biotechnology will be interested in the topics discussed in the book.
A Novel Mode of Bacterial Respiration
Title | A Novel Mode of Bacterial Respiration PDF eBook |
Author | Christine Michelle Fennessey |
Publisher | |
Pages | |
Release | 2010 |
Genre | Microbial respiration |
ISBN |
Microbial iron respiration contributes significantly to the biogeochemical cycling of metals and may be one of the earliest respiratory processes to have evolved on early earth. Metal-respiring microbes also hold great potential for use in microbial fuel cells for the generation of "green" energy and for remediation of radionuclides in contaminated environments. Despite its significance in global metal cycling processes, the molecular mechanism of Fe(III) respiration has yet to be determined. Unlike many other terminal electron acceptors, Fe(III) is a solid at circumneutral pH and, therefore, cannot come into direct contact with the microbial inner membrane: the site of terminal electron transfer in gram-negative bacteria. It is postulated that metal-respiring organisms have developed alternate strategies for the reduction of solid iron. One such strategy involves the production of an Fe(III)-solublizing ligand by the metal-respiring bacteria which solubilizes the Fe(III) prior to respiration, rendering the metal more easily accessible to the Fe(III) reductase complex. :In this study, the genes involved in the solubilization of Fe(III) by the gram-negative dissimilatory metal reducing bacteria Shewanella oneidensis MR-1 were determined using random mutagenesis to generate mutations in the wild-type genome and high-throughput square-wave voltammetry to screen for the attenuation of Fe(III) production in the mutants. Two mutants unable to solubilize Fe(III) were identified and designated d29 and d64. After mutation complementation analysis, it was determined that the point mutations were both located in type II secretion genes: gspG and gspE respectively, indicating that the type II secretion system is required for Fe(III) solubilization prior to respiration.
Microbial Respiration
Title | Microbial Respiration PDF eBook |
Author | Walter P. Hempfling |
Publisher | Hutchinson Ross Publishing Company |
Pages | 360 |
Release | 1979 |
Genre | Medical |
ISBN |
Prokaryotic Metabolism and Physiology
Title | Prokaryotic Metabolism and Physiology PDF eBook |
Author | Byung Hong Kim |
Publisher | Cambridge University Press |
Pages | 509 |
Release | 2019-05-16 |
Genre | Medical |
ISBN | 1107171733 |
Extensive and up-to-date review of key metabolic processes in bacteria and archaea and how metabolism is regulated under various conditions.