Metals in Biology

Pure and Applied Chemistry, 2007

Metals have complex environmental chemistry. When metals are present at elevated levels, they cause toxicity. Some metals are essential for living organisms, and those metals occur naturally in the environment. The latter aspect has allowed biological species to adapt to long- and short-term variations in metal levels. Chemical speciation, bioavailability, bioaccumulation, toxicity, and mixture effects are key issues in assessing the hazards of metals.In the present contribution, a global overview is given of the interactions between the chemistry and biology of metals, mostly at the interface of biological and environmental matrices. The environmental chemistry of metals and resulting methods for assessing metal availability are assumed as tokens, and the emphasis is thus on biological processes affecting the fate and effects of metals following interaction of the organism with the bioavailable metal fraction. The overview culminates in linking metal compartmentalization in organis...

Communications Chemistry, 2020

First-row transition metals play several roles in biological processes and in medicine, but can be toxic in high concentrations. Here the authors comment on the sensitive biochemistry and speciation chemistry of the first-row transition metals, and outline some of the remaining questions that have yet to be answered. Five of the ten first-row transition metals are essential to human health, including manganese, iron, cobalt, copper, and zinc 1,2. Three more first-row transition elements have shown some beneficial biological effects including chromium, vanadium, and nickel. Typically, these metals are consumed in a varied diet or as nutritional additives where, in the human body, they serve both structural and functional roles including the maintenance of cellular functions involved in a wide range of biological activities. However, normal function requires that the levels of the metal ions are maintained within an acceptable range; lower concentrations may result in a nutritional deficiency and higher concentrations may result in toxicity (Fig. 1) 3. In addition, the physical properties of first-row elements, particularly titanium and nickel, are important for preparation of new materials and alloys, resulting in technological advantages that improve the quality of life. Nine of the ten first-row transition metals have densities larger than 5.0 g/cm 3 which, by some definitions, classifies them as 'heavy metals'. Although this definition may be commonly used by some, it is not embraced by chemists primarily because this definition depends on the density of the metal rather than its chemical properties. Furthermore, the negative connotation associated with the term 'heavy metal' and the toxicity of metals such as cadmium and mercury stands in opposition to the fact that five of the first-row transition elements are essential to life. A more concise definition of the vague term 'heavy metal' can be based on chemical properties and would include the block of metals in Groups 3 to 16 that are in periods 4 and greater 4. This definition of 'heavy metals' does not involve first-row elements but only second and third-row transition metals. However, even this definition is debated 4. It is however clear that none of the five essential first-row transition metals are toxic 'heavy metals'. The chemistry of all first-row transition metals is very sensitive to their environment 6. In the presence of water, each metal ion forms hydrated ions which undergo pH and concentrationdependent chemistry that is dictated by the presence of metabolites, proteins, and other biological components (Fig. 1a). It is important to recognize that redox active metal ions do not exist

Journal of Analytical Atomic Spectrometry, 2004

In this paper, ''metallomics'' is proposed as a new scientific field in order to integrate the research fields related to biometals. Metallomics should be a scientific field in symbiosis with genomics and proteomics, because syntheses and metabolic functions of genes (DNA and RNA) and proteins cannot be performed without the aid of various metal ions and metalloenzymes. In metallomics, metalloproteins, metalloenzymes and other metal-containing biomolecules are defined as ''metallomes'', in a similar manner to genomes in genomics as well as proteomes in proteomics. Since the identification of metallomes and the elucidation of their biological or physiological functions in the biological systems is the main research target of metallomics, chemical speciation for specific identification of bioactive metallomes is one of the most important analytical technologies to establish metallomics as the integrated bio-metal science. In order to rationalize the concept of metallomics, the distributions of the elements in man, human blood serum and sea-water, a challenge to allelements analysis of one biological cell, and some other research topics are introduced with emphasis on recent development of chemical speciation of trace metals in some biological samples.

2020

Biological transition metal-sulfur sites are known for almost all so-called essential transition metal ions. Metalloenzymes based on such metal-sulfur sites catalyze some red-hot chemical reactions and a better understanding of the related processes might therefore solve existential problems of mankind in future. Enzymes with metal-sulfur sites promising such an impact are for example nitrogenases with P-cluster and a [Mo-7Fe-9S-C]-homocitrate catalytic site or carbon monoxide dehydrogenases and hydrogenases with NiFeS sites, just to name a few examples. Therefore, the 20th volume of the ‘Metal Ions in Life Sciences’ series edited by ‘the Sigels’ (Astrid Sigel, Eva Freisinger, Roland K.O. Sigel) is dedicated to sulfur and metal-sulfur sites and covers many aspects and a tremendous amount of information one could hardly extract and compile oneself in 12 chapters. Thus, this 20th volume certainly fills a gap in the metal ions in life science field and answers several questions a lectu...

Current Opinion in Biotechnology, 2012

The vital nature of metal uptake and balance in biology is evident in the highly evolved strategies to facilitate metal homeostasis in all three domains of life. Several decades of study on metals and metalloproteins have revealed numerous essential bio-metal functions. Recent advances in mass spectrometry, X-ray scattering/absorption, and proteomics have exposed a much broader usage of metals in biology than expected. Even elements such as uranium, arsenic, and lead are implicated in biological processes as part of an emerging and expansive view of bio-metals. Here we discuss opportunities and challenges for established and newer approaches to study metalloproteins with a focus on technologies that promise to rapidly expand our knowledge of metalloproteins and metal functions in biology.

Frontiers in Cell and Developmental Biology, 2022

Investigations of biology and the origins of life regularly focus on the components of the central dogma and thus the elements that compose nucleic acids and peptides. Less attention is given to the inorganic components of a biological cell, which are required for biological polymers to function. The Earth was and continues to be rich in metals, and so investigations of the emergence and evolution of life must account for the role that metal ions play. Evolution is shaped by what is present, and not all elements of the periodic table are equally accessible. The presence of metals, the solubility of their ions, and their intrinsic reactivity all impacted the composition of the cells that emerged. Geological and bioinformatic analyses clearly show that the suite of accessible metal ions changed over the history of the Earth; however, such analyses tend to be interpreted in comparison to average oceanic conditions, which do not represent well the many niche environments present on the ...

Open Journal of Plant Science, 2018

Research activities and data collection of metals present in living organisms are called as "metallomics". In metallomics, biomolecules incorporating metal ions viz. metalloenzymes and metalloproteins, are known as "metallomes". Metallomics aims to identify metallomes of living organisms and to annotate the physiological signifi cance as well as the biological functions. However, in order to ascertain metallomics to be the part of biometal science, recent analytical technologies like chemical speciation are required to analyze the metallomes. Environmental applications like bioleaching, phytoremediation of soil by using microbes, and to deal with the uptake, transport, storage of trace metals necessary for protein functions and biomarkers identifi cation under ecotoxicological studies really require metallomics involvement. As an interdisciplinary research area, metallomics cover plant and animal physiology, nutrition and become a potential candidate in pharmacology, biogeochemistry and clinical chemistry. Metallomics uses analytical and spectroscopic methods to fi nd the quantitative and qualitative information about metal ions that are present as ligands a well multifaceted biological matrix in trace amounts or occur as noncovalent complexes in order to perform different biological processes. Latest spectroscopic methods along with in-silico approaches including bioinformatics are the important tools needed for research activities in metallomics. The present review highlights the basics of metallomics in biological sciences and its emergence as a novel omics era in relation to other fi elds. Besides the above aspects, applications and future prospects of metallomics have been highlighted.

2000

Coordination Chemistry Reviews, 2005