Metallomics最新文献_第10页

Diet, cellular, and systemic homeostasis control the cycling of potassium stable isotopes in endothermic vertebrates. 饮食、细胞和系统稳态控制吸热脊椎动物中钾稳定同位素的循环。

IF 3.4 3区生物学

Metallomics Pub Date : 2023-11-02 DOI: 10.1093/mtomcs/mfad065

T Tacail, J Lewis, M Clauss, C D Coath, R Evershed, E Albalat, T R Elliott, T Tütken

{"title":"Diet, cellular, and systemic homeostasis control the cycling of potassium stable isotopes in endothermic vertebrates.","authors":"T Tacail, J Lewis, M Clauss, C D Coath, R Evershed, E Albalat, T R Elliott, T Tütken","doi":"10.1093/mtomcs/mfad065","DOIUrl":"10.1093/mtomcs/mfad065","url":null,"abstract":"The naturally occurring stable isotopes of potassium (41K/39K, expressed as δ41K) have the potential to make significant contributions to vertebrate and human biology. The utility of K stable isotopes is, however, conditioned by the understanding of the dietary and biological factors controlling natural variability of δ41K. This paper reports a systematic study of K isotopes in extant terrestrial endothermic vertebrates. δ41K has been measured in 158 samples of tissues, biofluids, and excreta from 40 individuals of four vertebrate species (rat, guinea pig, pig and quail) reared in two controlled feeding experiments. We show that biological processing of K by endothermic vertebrates produces remarkable intra-organism δ41K variations of ca. 1.6‰. Dietary δ41K is the primary control of interindividual variability and δ41K of bodily K is +0.5-0.6‰ higher than diet. Such a trophic isotope effect is expected to propagate throughout trophic chains, opening promising use for reconstructing dietary behaviors in vertebrate ecosystems. In individuals, cellular δ41K is related to the intensity of K cycling and effectors of K homeostasis, including plasma membrane permeability and electrical potential. Renal and intestinal transepithelial transports also control fractionation of K isotopes. Using a box-modeling approach, we establish a first model of K isotope homeostasis. We predict a strong sensitivity of δ41K to variations of intracellular and renal K cycling in normal and pathological contexts. Thus, K isotopes constitute a promising tool for the study of K dyshomeostasis.","PeriodicalId":89,"journal":{"name":"Metallomics","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49671783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thallium hyperaccumulation status of the violets of the Allchar arsenic-thallium deposit (North Macedonia) confirmed through synchrotron µXRF imaging. 通过同步加速器μXRF成像证实了Allchar砷铊矿床（北马其顿）紫罗兰的铊超富集状态。

IF 3.4 3区生物学

Metallomics Pub Date : 2023-11-02 DOI: 10.1093/mtomcs/mfad063

Ksenija Jakovljević, Tomica Mišljenović, Katerina Bačeva Andonovska, Guillaume Echevarria, Alan J M Baker, Dennis Brueckner, Antony van der Ent

{"title":"Thallium hyperaccumulation status of the violets of the Allchar arsenic-thallium deposit (North Macedonia) confirmed through synchrotron µXRF imaging.","authors":"Ksenija Jakovljević, Tomica Mišljenović, Katerina Bačeva Andonovska, Guillaume Echevarria, Alan J M Baker, Dennis Brueckner, Antony van der Ent","doi":"10.1093/mtomcs/mfad063","DOIUrl":"10.1093/mtomcs/mfad063","url":null,"abstract":"The abandoned Allchar Mine in the Republic of North Macedonia is a globally unique deposit with the highest known grades of thallium (Tl) and arsenic (As) mineralization. We aimed to determine the distribution of As and Tl in whole dehydrated shoots of the three Viola taxa using synchrotron micro-X-ray fluorescence analysis. Additionally, soil and plant organ samples were collected from all three Viola taxa at the Allchar site and analysed using inductively coupled plasma-atomic emission spectrometry. Concentrations of Tl were extremely high in all three Viola taxa (up to 58 900 mg kg-1), but concentrations of As were highly variable with V. tricolor subsp. macedonica and V. allchariensis having low As (up to 20.2 and 26.3 mg kg-1, respectively) and V. arsenica having the highest concentrations (up to 381 mg kg-1). The extremely high Tl in all three species is endogenous and not a result of contamination. Arsenic in V. tricolor subsp. macedonica and V. allcharensis is strongly affected by contamination, but not in V. arsenica where it appears to be endogenous. The pattern of As enrichment in V. arsenica is very unusual and coincides with Ca-oxalate deposits and Br hotspots. The results of this study could form the basis for more detailed investigations under controlled conditions, including plant dosing experiments.","PeriodicalId":89,"journal":{"name":"Metallomics","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10639103/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41230547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Copper isotope ratios in serum do not track cancerous tumor evolution, but organ failure. 血清中的铜同位素比率不能追踪癌性肿瘤的演变，但可以追踪器官衰竭。

IF 3.4 3区生物学

Metallomics Pub Date : 2023-11-02 DOI: 10.1093/mtomcs/mfad060

Emily Miaou, François L H Tissot

{"title":"Copper isotope ratios in serum do not track cancerous tumor evolution, but organ failure.","authors":"Emily Miaou, François L H Tissot","doi":"10.1093/mtomcs/mfad060","DOIUrl":"10.1093/mtomcs/mfad060","url":null,"abstract":"Relative to healthy controls, lighter copper isotopic compositions have been observed in the serum of breast cancer and end-stage liver disease patients, raising the possibility that Cu isotope ratios could be used as a tracer for disease progression. Here, we assess the potential of natural Cu isotopic variations (expressed as δ65Cu) as diagnostic tools for cancer progression and/or liver failure by performing a first-order analysis of Cu isotopic cycling in the human body. Using a box model, we simulate the kinetics of Cu mass transfer throughout significant reservoirs in the body, allowing isotopic fractionation to occur during Cu uptake/release from these reservoirs. With this model, we determine under which conditions the serum δ65Cu values would reflect perturbation related to cancer growth and/or liver failure at a level resolvable with modern mass spectrometry. We find that tumor growth alone is unable to explain the light isotopic signature observed in serum. Instead, we find that metabolic changes to the liver function resulting in a ∼1‰ isotope fractionation during Cu uptake from the blood into the liver can readily explain the long-term serum isotopic shift of ∼0.2‰ observed in cancer patients. A similar fractionation (∼1.3‰) during Cu uptake into the liver also readily explains the -1.2‰ shift observed in the serum of cirrhosis patients with ascites, suggesting a potentially common driver of isotopic fractionation in both cases. Using this model, we then test hypotheses put forward by previous studies and begin to probe the mechanisms behind the measured isotopic compositions.","PeriodicalId":89,"journal":{"name":"Metallomics","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41098193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Selenomethionine supplementation and expression of selenosugars, selenocysteine, and other selenometabolites in rat liver. 硒代蛋氨酸的补充和硒糖、硒代半胱氨酸和其他硒代代谢产物在大鼠肝脏中的表达。

IF 3.4 3区生物学

Metallomics Pub Date : 2023-11-02 DOI: 10.1093/mtomcs/mfad067

Katarzyna Bierla, Joanna Szpunar, Ryszard Lobinski, Roger A Sunde

{"title":"Selenomethionine supplementation and expression of selenosugars, selenocysteine, and other selenometabolites in rat liver.","authors":"Katarzyna Bierla, Joanna Szpunar, Ryszard Lobinski, Roger A Sunde","doi":"10.1093/mtomcs/mfad067","DOIUrl":"10.1093/mtomcs/mfad067","url":null,"abstract":"Selenomethionine (SeMet) as a methionine analog can be incorporated into protein. In turkeys, we recently found that selenium (Se) as selenite is not metabolized to SeMet but rather to selenosugars (seleno-N-acetyl galactosamine) bound to protein as well as to selenocysteine (Sec) in selenoproteins. To characterize the metabolism of SeMet, we fed rats graded levels of SeMet from 0 to 5 µg Se/g in a Se-deficient diet for 4 wk, and investigated the fate and accumulation of liver Se using high pressure liquid chromatography (HPLC) coupled with Se-specific inductively coupled plasma mass spectrometry (ICP-MS) and molecule specific (Orbitrap MS/MS) detection. Up to 0.24 µg Se/g (Se requirement for maximal glutathione peroxidase activity), Sec accounted for ∼40% of total liver Se whereas SeMet only accounted for 3-11%. Analysis of water-soluble extracts found negligible low molecular weight (LMW) Se species in rats fed 0 and 0.08 µg Se/g, including no SeMet. At 0.24 µg Se/g and above, SeMet accounted for only 10% of LMW Se species, whereas methyl- and glutathionyl-selenosugars accounted for 70% of LMW Se species. Above the Se requirement, SeMet was ∼30% of the proteinaceous amino acids, whereas Sec levels fell to 5% in rats fed 5 µg Se/g as SeMet. Last, considerably less inorganic Se was bound to liver protein with high SeMet as compared to selenite in a parallel study. SeMet is efficiently metabolized and mixes with the common Se metabolite pool, where Se is preferentially incorporated into Sec and Sec-selenoproteins until selenoproteins plateau; with high SeMet intake, Se is increasingly accumulated as LMW selenosugars and as selenosugar-decorated proteins.","PeriodicalId":89,"journal":{"name":"Metallomics","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66783242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of graded levels of selenium supplementation as selenite on expression of selenosugars, selenocysteine, and other selenometabolites in rat liver. 以亚硒酸盐形式分级补充硒对大鼠肝脏中硒糖、硒代半胱氨酸和其他硒代谢产物表达的影响。

IF 3.4 3区生物学

Metallomics Pub Date : 2023-11-02 DOI: 10.1093/mtomcs/mfad066

Katarzyna Bierla, Joanna Szpunar, Ryszard Lobinski, Roger A Sunde

{"title":"Effect of graded levels of selenium supplementation as selenite on expression of selenosugars, selenocysteine, and other selenometabolites in rat liver.","authors":"Katarzyna Bierla, Joanna Szpunar, Ryszard Lobinski, Roger A Sunde","doi":"10.1093/mtomcs/mfad066","DOIUrl":"10.1093/mtomcs/mfad066","url":null,"abstract":"Using high pressure liquid chromatography (HPLC) coupled with selenium-specific inductively coupled plasma mass spectrometry (ICP-MS) and molecule specific (Orbitrap MS/MS) detection, we previously found that far more selenium (Se) is present as selenosugar (seleno-N-acetyl galactosamine) in Se-adequate turkey liver than is present as selenocysteine (Sec) in true selenoproteins, and that selenosugars account for half of the Se in high-Se turkey liver. To expand these observations to mammals, we studied Se metabolism in rats fed graded levels of selenite from 0 to 5 μg Se/g for 4 wk. In Se-adequate (0.24 μg Se/g) rats, 43% of liver Se was present as Sec, 32% was present as selenosugars, and 22% as inorganic Se bound to protein. In liver of rats fed 5 μg Se/g as selenite, the quantity of Sec remained at the Se-adequate plateau (11% of total Se), 22% was present as low molecular weight (LMW) selenosugars with substantial additional selenosugars linked to protein, but 64% was present as inorganic Se bound to protein. No selenomethionine was found at any level of selenite supplementation. Below the Se requirement, Se is preferentially incorporated into Sec-selenoproteins. Above the dietary Se requirement, selenosugars become by far the major LMW water soluble Se species in liver, and levels of selenosugar-decorated proteins are far higher than Sec-selenoproteins, making these selenosugar-decorated proteins the major Se-containing protein species in liver with high Se supplementation. This accumulation of selenosugars linked to cysteines on proteins or the build-up of inorganic Se bound to protein may underlie Se toxicity at the molecular level.","PeriodicalId":89,"journal":{"name":"Metallomics","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66783241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

In vitro maturation of NiSOD reveals a role for cytoplasmic histidine in processing and metalation. NiSOD的体外成熟揭示了细胞质组氨酸在加工和金属化中的作用。

IF 2.9 3区生物学

Metallomics Pub Date : 2023-11-02 DOI: 10.1093/mtomcs/mfad054

Priyanka Basak, Diane E Cabelli, Peter T Chivers, Erik R Farquhar, Michael J Maroney

引用次数: 0

Mis-regulation of Zn and Mn homeostasis is a key phenotype of Cu stress in Streptococcus pyogenes. 锌和锰稳态失调是化脓性链球菌铜胁迫的一个关键表型。

IF 3.4 3区生物学

Metallomics Pub Date : 2023-11-02 DOI: 10.1093/mtomcs/mfad064

YoungJin Hong, Eilidh S Mackenzie, Samantha J Firth, Jack R F Bolton, Louisa J Stewart, Kevin J Waldron, Karrera Y Djoko

{"title":"Mis-regulation of Zn and Mn homeostasis is a key phenotype of Cu stress in Streptococcus pyogenes.","authors":"YoungJin Hong, Eilidh S Mackenzie, Samantha J Firth, Jack R F Bolton, Louisa J Stewart, Kevin J Waldron, Karrera Y Djoko","doi":"10.1093/mtomcs/mfad064","DOIUrl":"10.1093/mtomcs/mfad064","url":null,"abstract":"All bacteria possess homeostastic mechanisms that control the availability of micronutrient metals within the cell. Cross-talks between different metal homeostasis pathways within the same bacterial organism have been reported widely. In addition, there have been previous suggestions that some metal uptake transporters can promote adventitious uptake of the wrong metal. This work describes the cross-talk between Cu and the Zn and Mn homeostasis pathways in Group A Streptococcus (GAS). Using a ∆copA mutant strain that lacks the primary Cu efflux pump and thus traps excess Cu in the cytoplasm, we show that growth in the presence of supplemental Cu promotes downregulation of genes that contribute to Zn or Mn uptake. This effect is not associated with changes in cellular Zn or Mn levels. Co-supplementation of the culture medium with Zn or, to a lesser extent, Mn alleviates key Cu stress phenotypes, namely bacterial growth and secretion of the fermentation end-product lactate. However, neither co-supplemental Zn nor Mn influences cellular Cu levels or Cu availability in Cu-stressed cells. In addition, we provide evidence that the Zn or Mn uptake transporters in GAS do not promote Cu uptake. Together, the results from this study strengthen and extend our previous proposal that mis-regulation of Zn and Mn homeostasis is a key phenotype of Cu stress in GAS.","PeriodicalId":89,"journal":{"name":"Metallomics","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10644519/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41230546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evolution of Cd2+ and Cu+ binding in Helix pomatia metallothioneins. 螺旋波氏菌金属硫蛋白中Cd2+和Cu+结合的进化。

IF 3.4 3区生物学

Metallomics Pub Date : 2023-10-04 DOI: 10.1093/mtomcs/mfad057

Renato Valsecchi, Christian Baumann, Ardit Lila, Oliver Zerbe

{"title":"Evolution of Cd2+ and Cu+ binding in Helix pomatia metallothioneins.","authors":"Renato Valsecchi, Christian Baumann, Ardit Lila, Oliver Zerbe","doi":"10.1093/mtomcs/mfad057","DOIUrl":"https://doi.org/10.1093/mtomcs/mfad057","url":null,"abstract":"Metallothioneins (MTs) are small proteins present in all kingdoms of life. Their high cysteine content enables them to bind metal ions, such as Zn2+, Cd2+, and Cu+, providing means for detoxification and metal homeostasis. Three MT isoforms with distinct metal binding preferences are present in the Roman Snail Helix pomatia. Here, we use nuclear magnetic resonance (NMR) to follow the evolution of Cd2+ and Cu+ binding from the reconstructed ancestral Stylommatophora MT to the three H. pomatia MT (HpMT) isoforms. Information obtained from [15N,1H]-HSQC spectra and T2 relaxation times are combined to describe the conformational stability of the MT-metal complexes. A well-behaved MT-metal complex adopts a unique structure and does not undergo additional conformational exchange. The ancestor to all three HpMTs forms conformationally stable Cd2+ complexes and closely resembles the Cd2+-specific HpCdMT isoform, suggesting a role in Cd2+ detoxification for the ancestral protein. All Cu+-MT complexes, including the Cu+-specific HpCuMT isoform, undergo a considerable amount of conformational exchange. The unspecific HpCd/CuMT and the Cu+-specific HpCuMT isoforms form Cu+ complexes with comparable characteristics. It is possible to follow how Cd2+ and Cu+ binding changed throughout evolution. Interestingly, Cu+ binding improved independently in the lineages leading to the unspecific and the Cu+-specific HpMT isoforms. C-terminal domains are generally less capable of coordinating the non-cognate metal ion than N-terminal domains, indicating a higher level of specialization of the C-domain. Our findings provide new insights into snail MT evolution, helping to understand the interplay between biological function and structural features toward a comprehensive understanding of metal preference.","PeriodicalId":89,"journal":{"name":"Metallomics","volume":"15 10","pages":""},"PeriodicalIF":3.4,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10548783/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41097357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamic elementomics of single-cell ICP-MS-derived signals in normal and calcium pump PMCA4-deficient mouse epididymal sperm during capacitation. 正常和钙泵PMCA4缺陷小鼠附睾精子获能过程中单细胞ICP-MS衍生信号的动态元素组学。

IF 3.4 3区生物学

Metallomics Pub Date : 2023-10-04 DOI: 10.1093/mtomcs/mfad059

Bao Li Zhang, Ze Peng Zhang, Su Meng Shi, Hui Juan Shi, Patricia A DeLeon, Winnie Shum

{"title":"Dynamic elementomics of single-cell ICP-MS-derived signals in normal and calcium pump PMCA4-deficient mouse epididymal sperm during capacitation.","authors":"Bao Li Zhang, Ze Peng Zhang, Su Meng Shi, Hui Juan Shi, Patricia A DeLeon, Winnie Shum","doi":"10.1093/mtomcs/mfad059","DOIUrl":"10.1093/mtomcs/mfad059","url":null,"abstract":"Currently, clinical analysis of male infertility mainly relies on parameters of semen and sperm cells. However, the high diagnostic failure rates indicate that the current assessment methods are not sufficient and a new approach to evaluating sperm function still needs to be developed. Here we explored the feasibility of single-cell inductively coupled plasma mass spectrometry (sc-ICP-MS)-derived profiles to determine the elemental characteristics in viable capacitated sperm under normal and deficient conditions. To validate the measurements, we used male sterile Pmca4-knockout (KO) mice with impaired calcium clearance, known to be dysregulated due to loss of calcium efflux capacity during sperm capacitation. Consistently, we observed significantly increased calcium intensities in Pmca4-KO sperm upon capacitation stimulation compared with control sperm from the caudaepididymides of wild-type control (WT) mice. More importantly, we explored that the characteristic signatures of calcium intensities in individual spikes derived from sc-ICP-MS was consistent with the dynamics of relative calcium levels in single sperm reported in the literature. Prominent alterations were also observed in the dynamic signatures of sc-ICP-MS-derived profiles of essential elements, particularly the redox-labile elements including copper, iron, manganese, selenium, and zinc in Pmca4-KO sperm compared to WT controls. Therefore, our study demonstrates that elementomics of sc-ICP-MS-derived signals can reveal ionic dysregulation in plasma membrane Ca2+-ATPase isoform 4 protein deficient sperm, and that sc-ICP-MS assay can be applied for functional analysis of viable sperm in functional activities, such as capacitation stimulation. We propose that cell elementomics can be used as an alternative approach to assessing sperm quality and male fertility at the single-cell level.","PeriodicalId":89,"journal":{"name":"Metallomics","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41092255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Differentiated Zn(II) binding affinities in animal, plant, and bacterial metallothioneins define their zinc buffering capacity at physiological pZn. 动物、植物和细菌金属硫蛋白中分化的Zn（II）结合亲和力定义了它们在生理pZn下的锌缓冲能力。

IF 3.4 3区生物学

Metallomics Pub Date : 2023-10-04 DOI: 10.1093/mtomcs/mfad061

Karolina Mosna, Kinga Jurczak, Artur Krężel

{"title":"Differentiated Zn(II) binding affinities in animal, plant, and bacterial metallothioneins define their zinc buffering capacity at physiological pZn.","authors":"Karolina Mosna, Kinga Jurczak, Artur Krężel","doi":"10.1093/mtomcs/mfad061","DOIUrl":"10.1093/mtomcs/mfad061","url":null,"abstract":"Metallothioneins (MTs) are small, Cys-rich proteins present in various but not all organisms, from bacteria to humans. They participate in zinc and copper metabolism, toxic metals detoxification, and protection against reactive species. Structurally, they contain one or multiple domains, capable of binding a variable number of metal ions. For experimental convenience, biochemical characterization of MTs is mainly performed on Cd(II)-loaded proteins, frequently omitting or limiting Zn(II) binding features and related functions. Here, by choosing 10 MTs with relatively well-characterized structures from animals, plants, and bacteria, we focused on poorly investigated Zn(II)-to-protein affinities, stability-structure relations, and the speciation of individual complexes. For that purpose, MTs were characterized in terms of stoichiometry, pH-dependent Zn(II) binding, and competition with chromogenic and fluorescent probes. To shed more light on protein folding and its relation with Zn(II) affinity, reactivity of variously Zn(II)-loaded MTs was studied by (5,5'-dithiobis(2-nitrobenzoic acid) oxidation in the presence of mild chelators. The results show that animal and plant MTs, despite their architectural differences, demonstrate the same affinities to Zn(II), varying from nano- to low picomolar range. Bacterial MTs bind Zn(II) more tightly but, importantly, with different affinities from low picomolar to low femtomolar range. The presence of weak, moderate, and tight zinc sites is related to the folding mechanisms and internal electrostatic interactions. Differentiated affinities of all MTs define their zinc buffering capacity required for Zn(II) donation and acceptance at various free Zn(II) concentrations (pZn levels). The data demonstrate critical roles of individual Zn(II)-depleted MT species in zinc buffering processes.","PeriodicalId":89,"journal":{"name":"Metallomics","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10612145/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41092321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0