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Li M, Zuo J, Yang K, Wang P, Zhou S. Proteomics mining of cancer hallmarks on a single-cell resolution. MASS SPECTROMETRY REVIEWS 2024; 43:1019-1040. [PMID: 37051664 DOI: 10.1002/mas.21842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 11/25/2022] [Accepted: 03/15/2023] [Indexed: 06/19/2023]
Abstract
Dysregulated proteome is an essential contributor in carcinogenesis. Protein fluctuations fuel the progression of malignant transformation, such as uncontrolled proliferation, metastasis, and chemo/radiotherapy resistance, which severely impair therapeutic effectiveness and cause disease recurrence and eventually mortality among cancer patients. Cellular heterogeneity is widely observed in cancer and numerous cell subtypes have been characterized that greatly influence cancer progression. Population-averaged research may not fully reveal the heterogeneity, leading to inaccurate conclusions. Thus, deep mining of the multiplex proteome at the single-cell resolution will provide new insights into cancer biology, to develop prognostic biomarkers and treatments. Considering the recent advances in single-cell proteomics, herein we review several novel technologies with particular focus on single-cell mass spectrometry analysis, and summarize their advantages and practical applications in the diagnosis and treatment for cancer. Technological development in single-cell proteomics will bring a paradigm shift in cancer detection, intervention, and therapy.
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Affiliation(s)
- Maomao Li
- Department of Obstetrics and Gynecology, Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE and State Key Laboratory of Biotherapy, West China Second University Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, Sichuan, China
| | - Jing Zuo
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, and West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University and Collaborative Innovation Center for Biotherapy, Chengdu, Sichuan, China
| | - Kailin Yang
- Department of Radiation Oncology, Taussig Cancer Center, Cleveland Clinic, Cleveland, Ohio, USA
| | - Ping Wang
- Department of Obstetrics and Gynecology, Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE and State Key Laboratory of Biotherapy, West China Second University Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, Sichuan, China
| | - Shengtao Zhou
- Department of Obstetrics and Gynecology, Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE and State Key Laboratory of Biotherapy, West China Second University Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, Sichuan, China
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Tsutsumi C, Uegaki K, Yamashita R, Ushioda R, Nagata K. Zn 2+-dependent functional switching of ERp18, an ER-resident thioredoxin-like protein. Cell Rep 2024; 43:113682. [PMID: 38330940 DOI: 10.1016/j.celrep.2024.113682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 11/14/2023] [Accepted: 01/02/2024] [Indexed: 02/10/2024] Open
Abstract
ERp18 is an endoplasmic reticulum (ER)-resident thioredoxin (Trx) family protein, similar to cytosolic Trx1. The Trx-like domain occupies a major portion of the whole ERp18 structure, which is postulated to be an ER paralog of cytosolic Trx1. Here, we elucidate that zinc ion (Zn2+) binds ERp18 through its catalytic motif, triggering oligomerization of ERp18 from a monomer to a trimer. While the monomeric ERp18 has disulfide oxidoreductase activity, the trimeric ERp18 acquires scavenger activity for hydrogen peroxide (H2O2) in the ER. Depletion of ERp18 thus causes the accumulation of H2O2, which is produced during the oxidative folding of nascent polypeptides in the ER. ERp18 knockdown in C. elegans without Prx4 and GPx7/8, both of which are also known to have H2O2 scavenging activity in the ER, shortened the lifespan, suggesting that ERp18 may form a primitive and essential H2O2 scavenging system for the maintenance of redox homeostasis in the ER.
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Affiliation(s)
- Chika Tsutsumi
- Department of Molecular Biosciences, Faculty of Life Sciences, Kyoto Sangyo University, Kyoto 603-8555, Japan
| | - Kaiku Uegaki
- Howard Hughes Medical Institute and Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA
| | - Riyuji Yamashita
- Department of Molecular Biosciences, Faculty of Life Sciences, Kyoto Sangyo University, Kyoto 603-8555, Japan
| | - Ryo Ushioda
- Department of Molecular Biosciences, Faculty of Life Sciences, Kyoto Sangyo University, Kyoto 603-8555, Japan; Institute for Protein Dynamics, Kyoto Sangyo University, Kyoto 603-8555, Japan; Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Saitama 332-0012, Japan.
| | - Kazuhiro Nagata
- Department of Molecular Biosciences, Faculty of Life Sciences, Kyoto Sangyo University, Kyoto 603-8555, Japan; Institute for Protein Dynamics, Kyoto Sangyo University, Kyoto 603-8555, Japan; JT Biohistory Research Hall, Murasaki Town 1-1, Takatsuki City, Osaka 569-1125, Japan; Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Saitama 332-0012, Japan.
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Kuru Cİ, Ulucan-Karnak F, Dayıoğlu B, Şahinler M, Şendemir A, Akgöl S. Affinity-Based Magnetic Nanoparticle Development for Cancer Stem Cell Isolation. Polymers (Basel) 2024; 16:196. [PMID: 38256995 PMCID: PMC10818538 DOI: 10.3390/polym16020196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/06/2023] [Accepted: 12/27/2023] [Indexed: 01/24/2024] Open
Abstract
Cancer is still the leading cause of death in the world despite the developing research and treatment opportunities. Failure of these treatments is generally associated with cancer stem cells (CSCs), which cause metastasis and are defined by their resistance to radio- and chemotherapy. Although known stem cell isolation methods are not sufficient for CSC isolation, they also bring a burden in terms of cost. The aim of this study is to develop a high-efficiency, low-cost, specific method for cancer stem cell isolation with magnetic functional nanoparticles. This study, unlike the stem cell isolation techniques (MACS, FACS) used today, was aimed to isolate cancer stem cells (separation of CD133+ cells) with nanoparticles with specific affinity and modification properties. For this purpose, affinity-based magnetic nanoparticles were synthesized and characterized by providing surface activity and chemical reactivity, as well as making surface modifications necessary for both lectin affinity and metal affinity interactions. In the other part of the study, synthesized and characterized functional polymeric magnetic nanoparticles were used for the isolation of CSC from the human osteosarcoma cancer cell line (SAOS-2) with a cancer stem cell subpopulation bearing the CD133 surface marker. The success and efficiency of separation after stem cell isolation were evaluated via the MACS and FACS methods. As a result, when the His-graft-mg-p(HEMA) nanoparticle was used at a concentration of 0.1 µg/mL for 106 and 108 cells, superior separation efficiency to commercial microbeads was obtained.
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Affiliation(s)
- Cansu İlke Kuru
- Department of Biochemistry, Faculty of Science, Ege University, 35100 İzmir, Turkey; (C.İ.K.); (S.A.)
| | - Fulden Ulucan-Karnak
- Department of Biochemistry, Faculty of Science, Ege University, 35100 İzmir, Turkey; (C.İ.K.); (S.A.)
| | - Büşra Dayıoğlu
- Department of Bioengineering, Faculty of Engineering, Ege University, 35100 İzmir, Turkey; (B.D.); (M.Ş.); (A.Ş.)
| | - Mert Şahinler
- Department of Bioengineering, Faculty of Engineering, Ege University, 35100 İzmir, Turkey; (B.D.); (M.Ş.); (A.Ş.)
| | - Aylin Şendemir
- Department of Bioengineering, Faculty of Engineering, Ege University, 35100 İzmir, Turkey; (B.D.); (M.Ş.); (A.Ş.)
| | - Sinan Akgöl
- Department of Biochemistry, Faculty of Science, Ege University, 35100 İzmir, Turkey; (C.İ.K.); (S.A.)
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Rai KK, Singh S, Rai R, Rai LC. Functional characterization of two WD40 family proteins, Alr0671 and All2352, from Anabaena PCC 7120 and deciphering their role in abiotic stress management. PLANT MOLECULAR BIOLOGY 2022; 110:545-563. [PMID: 35997919 DOI: 10.1007/s11103-022-01306-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 08/01/2022] [Indexed: 06/15/2023]
Abstract
WD40 domain-containing proteins are one of the eukaryotes' most ancient and ubiquitous protein families. Little is known about the presence and function of these proteins in cyanobacteria in general and Anabaena in particular. In silico analysis confirmed the presence of WD40 repeats. Gene expression analysis indicated that the transcript levels of both the target proteins were up-regulated up to 4 fold in Cd and drought and 2-3 fold in heat, salt, and UV-B stress. Using a fluorescent oxidative stress indicator, we showed that the recombinant proteins were scavenging reactive oxygen species (ROS) (4-5 fold) more efficiently than empty vectors. Chromatin immunoprecipitation analysis (ChIP) and electrophoretic mobility shift assay (EMSA) revealed that the target proteins function as transcription factors after binding to the promoter sequences. The presence of kinase activity (2-4 fold) in the selected proteins indicated that these proteins could modulate the functions of other cellular proteins under stress conditions by inducing phosphorylation of specific amino acids. The chosen proteins also demonstrated interaction with Zn, Cd, and Cu (1.4-2.5 fold), which might stabilize the proteins' structure and biophysical functions under multiple abiotic stresses. The functionally characterized Alr0671 and All2352 proteins act as transcription factors and offer tolerance to agriculturally relevant abiotic stresses.
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Affiliation(s)
- Krishna Kumar Rai
- Molecular Biology Section, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, 221005, Varanasi, India
| | - Shilpi Singh
- Molecular Biology Section, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, 221005, Varanasi, India
| | - Ruchi Rai
- Molecular Biology Section, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, 221005, Varanasi, India
| | - L C Rai
- Molecular Biology Section, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, 221005, Varanasi, India.
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El-Seify FA, Azab HA, Degedy FS, Abdel-Mageed KA, El-Dossoki FI. Physico-analytical studies on some heterocyclic azo dyes and their metal complexes with some transition metals. BMC Chem 2022; 16:40. [PMID: 35637518 PMCID: PMC9153159 DOI: 10.1186/s13065-022-00833-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 05/19/2022] [Indexed: 11/23/2022] Open
Abstract
In this investigation, the azo dyes; 2-(3′-phenyl-5′-pyrazolyl azo) schaffer acid (la) and 2-(3′-phenyl-5′-pyrazolyl azo) resorcinol (Ib); were prepared through diazotizing 3-phenyl-5-aminopyrazole (PAP) and coupling the resulting diazonium salt with Schäffer acid and resorcinol respectively. The prepared azo dyes are characterized using both IR spectra and the elemental analysis (C, H, N and S). The prepared azo dyes are used as chromogenic reagents for the spectrophotometric determination of copper (II), nickel (II), cobalt (II) and zinc (II) ions. The conditional acid dissociation constants of these azo dyes (la and Ib) and the stability constants of its metal ion complexes have been determined by spectro-analytical methods. The effect of pH, time, organic solvent and the foreign ions on the spectrophotometric determination of these ions and their complexes with the azo dyes under study were studied. The stoichiometric ratio (M:L) of the formed complexes was also determined. The molar absorptivity, the Sandell's sensitivity values, the obeyance of Beers law and the stability constants of the formed complexes have been also determined and discussed.
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Affiliation(s)
- Fathy A El-Seify
- Chemistry Department, Faculty of Engineering, Port Said University, Port Said, Egypt
| | - Hassan A Azab
- Chemistry Department, Faculty of Science, Suez Canal University, Ismalia, Egypt
| | - Fikrea S Degedy
- Chemistry Department, Faculty of Science, Suez Canal University, Ismalia, Egypt
| | - Khalid A Abdel-Mageed
- Chemistry Department, Faculty of Engineering, Port Said University, Port Said, Egypt
| | - Farid I El-Dossoki
- Chemistry Department, Faculty of Science, Port Said University, Port Said, Egypt.
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Wang Y, Guo C, Wang X, Xu L, Li R, Wang J. The Zinc Content of HIV-1 NCp7 Affects Its Selectivity for Packaging Signal and Affinity for Stem-Loop 3. Viruses 2021; 13:v13101922. [PMID: 34696351 PMCID: PMC8540335 DOI: 10.3390/v13101922] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/19/2021] [Accepted: 09/21/2021] [Indexed: 11/16/2022] Open
Abstract
The nucleocapsid (NC) protein of human immunodeficiency (HIV) is a small, highly basic protein containing two CCHC zinc-finger motifs, which is cleaved from the NC domain of the Gag polyprotein during virus maturation. We previously reported that recombinant HIV-1 Gag and NCp7 overexpressed in an E. coli host contains two and one zinc ions, respectively, and Gag exhibited much higher selectivity for packaging signal (Psi) and affinity for the stem-loop (SL)-3 of Psi than NCp7. In this study, we prepared NCp7 containing 0 (0NCp7), 1 (NCp7) or 2 (2NCp7) zinc ions, and compared their secondary structure, Psi-selectivity and SL3-affinity. Along with the decrease of the zinc content, less ordered conformations were detected. Compared to NCp7, 2NCp7 exhibited a much higher Psi-selectivity and SL3-affinity, similar to Gag, whereas 0NCp7 exhibited a lower Psi-selectivity and SL3-affinity, similar to the H23&H44K double mutant of NCp7, indicating that the different RNA-binding property of Gag NC domain and the mature NCp7 may be resulted, at least partially, from their different zinc content. This study will be helpful to elucidate the critical roles that zinc played in the viral life cycle, and benefit further investigations of the functional switch from the NC domain of Gag to the mature NCp7.
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Affiliation(s)
- Ying Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin 300457, China; (Y.W.); (X.W.); (L.X.); (R.L.)
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, 23 Hongda Street, TEDA, Tianjin 300457, China
- Tianjin Key Laboratory of Microbial Functional Genomics, 23 Hongda Street, TEDA, Tianjin 300457, China
| | - Chao Guo
- College of Basic Medical Sciences, Shanxi Medical University, Taiyuan 030001, China;
| | - Xing Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin 300457, China; (Y.W.); (X.W.); (L.X.); (R.L.)
| | - Lianmei Xu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin 300457, China; (Y.W.); (X.W.); (L.X.); (R.L.)
| | - Rui Li
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin 300457, China; (Y.W.); (X.W.); (L.X.); (R.L.)
| | - Jinzhong Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin 300457, China; (Y.W.); (X.W.); (L.X.); (R.L.)
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, 23 Hongda Street, TEDA, Tianjin 300457, China
- Tianjin Key Laboratory of Microbial Functional Genomics, 23 Hongda Street, TEDA, Tianjin 300457, China
- Correspondence:
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Kamnoet P, Aeungmaitrepirom W, Menger RF, Henry CS. Highly selective simultaneous determination of Cu(ii), Co(ii), Ni(ii), Hg(ii), and Mn(ii) in water samples using microfluidic paper-based analytical devices. Analyst 2021; 146:2229-2239. [PMID: 33595555 PMCID: PMC8284785 DOI: 10.1039/d0an02200d] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A new paper-based analytical device design was fabricated by a wax printing method for simultaneous determination of Cu(ii), Co(ii), Ni(ii), Hg(ii), and Mn(ii). Colorimetry was used to quantify these heavy metal ions using bathocuproine (Bc), dimethylglyoxime (DMG), dithizone (DTZ), and 4-(2-pyridylazo) resorcinol (PAR) as complexing agents. The affinity of complexing agents to heavy metal ions is dependent on the formation constant (Kf). To enhance the selectivity for heavy metal ion determination, the new device was designed with two pretreatment zones, where masking agents remove the interfering ions. It was found that two pretreatment zones worked better than a single pretreatment zone at removing interferences. The reaction time, sample and complexing agent volumes, and complexing agent concentrations were optimized. The analytical results were achieved with the lowest detectable concentrations of 0.32, 0.59, 5.87, 0.20, and 0.11 mg L-1 for Cu(ii), Co(ii), Ni(ii), Hg(ii), and Mn(ii), respectively. The linear ranges were found to be 0.32-63.55 mg L-1 (Cu(ii)), 0.59-4.71 mg L-1 (Co(ii)), 5.87-352.16 mg L-1 (Ni(ii)), 0.20-12.04 mg L-1 (Hg(ii)), and 0.11-0.55 mg L-1 (Mn(ii)). The lowest detectable concentration and linearity for the five metal ions allow the application of this device for the determination of heavy metal ions in various water samples. The sensor showed high selectivity and efficiency for simultaneous determination of Cu(ii), Co(ii), Ni(ii), Hg(ii), and Mn(ii) in drinking, tap, and pond water samples on a single device and detection with the naked eye. The results illustrated that the proposed sensor showed good accuracy and precision agreement with the standard ICP-OES method.
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Affiliation(s)
- Pornphimon Kamnoet
- Environmental Analysis Research Unit (EARU), Department of Chemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok 10330, Thailand.
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Guo C, Yao X, Wang K, Wang J, Wang Y. Comparison of HIV-1 Gag and NCp7 in their selectivity for package signal, affinity for stem-loop 3, and Zn 2+ content. Biochimie 2020; 179:135-145. [PMID: 32987107 DOI: 10.1016/j.biochi.2020.09.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 09/22/2020] [Accepted: 09/23/2020] [Indexed: 11/17/2022]
Abstract
The human immunodeficiency virus type 1 (HIV-1) Gag recognizes viral packaging signal (Psi) specifically via its nucleocapsid (NC) domain, resulting in the encapsidation of two copies of genomic RNA (gRNA) into the viral particle. The NCp7, which is cleaved from Gag during viral maturation, is a nucleic acid chaperone, coating and protecting the gRNA. In this study, an RT-qPCR-based approach was developed to quantitatively compare the Psi-selectivity of Gag and NCp7 in the presence of bacterial or 293T total RNAs. The binding affinity of Gag and NCp7 to the stem-loop (SL) 3 of Psi was also compared using surface plasmon resonance. We found that Gag selected more Psi-RNA than NCp7 from both E. coli BL21 (DE3) and in vitro binding reactions, and Gag bound to SL3-RNA with a higher affinity than NCp7. Moreover, Gag contained two Zn2+ whereas NCp7 contained one. The N-terminal zinc-finger motif of NCp7 lost most of its Zn2+-binding activity. Deletion of N-terminal amino acids 1-11 of NCp7 resulted in increased Psi-selectivity, SL3-affinity and Zn2+ content. These results indicated that Zn2+ coordination of Gag is critical for Psi-binding and selection. Removal of Zn2+ from the first zinc-finger motif during or after Gag cleavage to generate mature NCp7 might serve as a switch to regulate the functions of Gag NC domain and mature NCp7. Our study will be helpful to elucidate the important roles that Zn2+ plays in the viral life cycle, and may benefit further investigations of the function of HIV-1 Gag and NCp7.
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Affiliation(s)
- Chao Guo
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin, 300457, China
| | - Xiaohong Yao
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin, 300457, China
| | - Kangkang Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin, 300457, China
| | - Jinzhong Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin, 300457, China; Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, 23 Hongda Street, TEDA, Tianjin, 300457, China; Tianjin Key Laboratory of Microbial Functional Genomics, 23 Hongda Street, TEDA, Tianjin, 300457, China.
| | - Ying Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin, 300457, China; Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, 23 Hongda Street, TEDA, Tianjin, 300457, China; Tianjin Key Laboratory of Microbial Functional Genomics, 23 Hongda Street, TEDA, Tianjin, 300457, China.
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Kokhan O, Marzolf DR. Detection and quantification of transition metal leaching in metal affinity chromatography with hydroxynaphthol blue. Anal Biochem 2019; 582:113347. [PMID: 31251926 DOI: 10.1016/j.ab.2019.113347] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 06/13/2019] [Accepted: 06/24/2019] [Indexed: 11/17/2022]
Abstract
The widespread use of immobilized metal-affinity chromatography (IMAC) for fast and efficient purification of recombinant proteins has brought potentially toxic transition elements into common laboratory usage. However, there are few studies on the leaching of metal from the affinity resin, such as nickel-nitrilotriacetic acid (Ni-NTA), with possible deleterious impact on the biological activity. This is of particular importance when reducing or chelating eluants stronger than imidazole are used. We present a detailed study of hydroxynaphthol blue (HNB) as an indicator of several divalent metal cations, but with emphasis on Ni2+, clarifying and correcting many errors and ambiguities in the older literature on this dye compound. The assay is simple and sensitive and many metals, notably Ni2+, Zn2+, Cu2+, Pb2+, Fe2+, Co2+, and Al3+, can be readily detected and quantified at concentrations down to 15-50 nM (1-5 ppb) at neutral pH and in most commonly used buffers using spectroscopic equipment available in typical biochemistry research labs. Using this method, we show that significant amounts of Ni2+ (up to 20 mM) are co-purified with a target protein (cytochrome bc1 complex) when histidine is used to elute from Ni-NTA resin.
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Affiliation(s)
- Oleksandr Kokhan
- Department of Chemistry and Biochemistry, James Madison University, 901 Carrier Drive, Harrisonburg, VA, 22807, USA.
| | - Daniel R Marzolf
- Department of Chemistry and Biochemistry, James Madison University, 901 Carrier Drive, Harrisonburg, VA, 22807, USA
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