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Joshi DJ, Lalrinhlupuii, Malek NI, Muthukumaran RB, Kailasa SK. Microwave-Assisted Synthesis of Red Emitting Copper Nanoclusters Using Trypsin as a Ligand for Sensing of Pb 2+ And Hg 2+ Ions in Water and Tobacco Samples. Appl Spectrosc 2022; 76:1234-1245. [PMID: 35477299 DOI: 10.1177/00037028221100544] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
In this work, a microwave assisted method was developed for synthesis of red fluorescent copper nanoclusters (NCs) using trypsin as a template (trypsin-Cu). The as-synthesized trypsin-Cu NCs are stable and water soluble, exhibiting fluorescence emission at 657 nm when excited at 490 nm. The as-prepared red-emitting trypsin-Cu NCs were characterized by using several analytical techniques such as ultraviolet-visible (UV-Vis) and fluorescence, fluorescence lifetime, Fourier transform infrared, and X-ray photoelectron spectroscopic techniques. Red-emitting trypsin-Cu NCs acted as a nanosensor for sensing both Pb2+ and Hg2+ ions through fluorescence quenching. Using this approach, good linearities are observed in the range of 0.1-25 and of 0.001-1 μM with the lower limit of detection of 14.63 and 56.81 nM for Pb2+ and Hg2+ ions, respectively. Trypsin-Cu NCs-based fluorescence assay was successfully applied to detect both Hg2+ and Pb2+ ions in water and tobacco samples.
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Affiliation(s)
- Dharaben J Joshi
- Department of Chemistry, 123518Sardar Vallabhbhai National Institute of Technology, Surat, India
| | - Lalrinhlupuii
- Department of Chemistry, 29670Mizoram University, Aizawl, India
| | - Naved I Malek
- Department of Chemistry, 123518Sardar Vallabhbhai National Institute of Technology, Surat, India
| | | | - Suresh Kumar Kailasa
- Department of Chemistry, 123518Sardar Vallabhbhai National Institute of Technology, Surat, India
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Lalrammawia K, Buragohain A, Kakki B, Zote L, Marak NK, Lalrinhlupuii, Malsawmtluangi, Lalmuanpuii R, Kumar NS, Jahau L, Sudarshan M, Chaligava O, Yushin N, Grozdov D, Nekhoroshkov P, Vergel K, Zinicovscaia I, Muthukumaran RB. Determination of Multi Elements in Tobacco Plant of Northeast India by Neutron Activation Analysis and Atomic Absorption Spectrometry. Biol Trace Elem Res 2022; 200:4534-4549. [PMID: 34820780 DOI: 10.1007/s12011-021-03040-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 11/17/2021] [Indexed: 01/30/2023]
Abstract
Even when cultivated in uncontaminated soils, tobacco plant has higher propensity to extract and accumulate trace elements. The concentrations (mass fractions) of essential elements (K, Ca, Mg, Na, Cl, Mn, Fe, Cu, and Zn) and 28 non-essential elements in tobacco plant (leaves, stem, and root) of Northeast India and their respective soils were quantitatively measured. Hg mass fraction in all samples analyzed were found to be < 10 mg/kg. The heavy element mass fractions of tobacco are weakly correlated to different soil parameters. The bioconcentration factor values indicated that Cd (7) is selectively absorbed and translocated in the tobacco leaves compared to Zn (1.7), Cu (1.5), Ni (0.12), and Pb (0.1). Under acidic soil conditions, tobacco plant efficiently absorbed and translocated Cl- ion with great ease, whereas it may be a very low accumulator of rare-earth elements. The mass fractions of Mn, Cu, Sb, Cs, Rb, and Pb are very similar to the "reference plant," whereas significantly higher mass fractions of Al, Sc, Ti, Zr, Hf, Ta, Th, and U are present in the roots of tobacco plant relative to the "reference plant." Principal component analysis has revealed that Northeast Indian tobacco can be clearly differentiated from other varieties of tobaccos used in different countries because of their element profiles.
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Affiliation(s)
| | | | - Bomngam Kakki
- Department of Chemistry, Mizoram University, Aizawl, 796 004, India
| | - Lalrinawma Zote
- Department of Chemistry, Mizoram University, Aizawl, 796 004, India
| | - Nikrang K Marak
- Department of Chemistry, Mizoram University, Aizawl, 796 004, India
| | - Lalrinhlupuii
- Department of Chemistry, Mizoram University, Aizawl, 796 004, India
| | - Malsawmtluangi
- Department of Chemistry, Mizoram University, Aizawl, 796 004, India
| | - Rebecca Lalmuanpuii
- Department of Chemistry, Government Serchhip College, Serchhip, Mizoram, India
| | | | - Lalrintluanga Jahau
- Centre for Rural Development Research and Trinity Diagnostic Centre, Aizawl, Mizoram, India
| | - Mathummal Sudarshan
- UGC-DAE Consortium for Scientific Research, Kolkata Centre, Kolkata, 700106, India
| | - Omari Chaligava
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russian Federation, 141980
- Georgian Technical University, 77, Merab Kostava Street, 0175, Tbilisi, Georgia
| | - Nikita Yushin
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russian Federation, 141980
| | - Dmitrii Grozdov
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russian Federation, 141980
| | - Pavel Nekhoroshkov
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russian Federation, 141980
| | - Konstantin Vergel
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russian Federation, 141980
| | - Inga Zinicovscaia
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russian Federation, 141980.
- Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering, 30 Reactorului Str., MG-6, Bucharest-Magurele, Romania.
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Chang YJ, Muthukumaran RB, Chen JL, Chang HY, Hung YC, Hu CW, Chao MR. Simultaneous determination of areca nut- and tobacco-specific alkaloids in saliva by LC-MS/MS: Distribution and transformation of alkaloids in oral cavity. J Hazard Mater 2022; 426:128116. [PMID: 34968842 DOI: 10.1016/j.jhazmat.2021.128116] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 12/13/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
Areca nut and tobacco are frequently used in combination. Cigarette smoking and betel quid (BQ) chewing habits impose greater oral cancer risk than either habit alone. Saliva is a better noninvasive diagnostic material as it is in direct contact with oral mucosa and cancerous lesions. This study describes the application of isotope-dilution LC-MS/MS for simultaneous quantitation of five areca nut-specific alkaloids (ASAs) and three tobacco-specific alkaloids (TSAs) in human saliva. With this method, we demonstrate that the distribution of ASAs vary significantly in smokers who chew BQ habitually, due to the hydrolysis of ASAs and metabolic activity in the oral cavity. The alkaline condition formed due to slaked lime in BQ, plays an important role in the distribution of ASAs and TSAs, by catalyzing the hydrolysis of ester forms of ASAs to their respective carboxylic acid forms besides facilitating the TSA (i.e., nicotine) absorption in the oral cavity. Moreover, our results reveal that oral mucosa rather than saliva contributes to the metabolism of ASAs at oral cavity. Less than 2.1% of ASAs were metabolized by saliva, as determined by in vitro test. Our findings may provide a better insight into the pathobiology of oral carcinogenesis due to BQ chewing.
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Affiliation(s)
- Yuan-Jhe Chang
- Department of Occupational Safety and Health, Chung Shan Medical University, Taichung 402, Taiwan; Department of Medical Research, Chung Shan Medical University Hospital, Taichung 402, Taiwan
| | | | - Jian-Lian Chen
- School of Pharmacy, China Medical University, Taichung 404, Taiwan
| | - Hsin-Yi Chang
- Department of Public Health, Chung Shan Medical University, Taichung 402, Taiwan
| | - Yu-Cheng Hung
- Department of Public Health, Chung Shan Medical University, Taichung 402, Taiwan
| | - Chiung-Wen Hu
- Department of Public Health, Chung Shan Medical University, Taichung 402, Taiwan.
| | - Mu-Rong Chao
- Department of Occupational Safety and Health, Chung Shan Medical University, Taichung 402, Taiwan; Department of Occupational Medicine, Chung Shan Medical University Hospital, Taichung 402, Taiwan.
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Zote L, Lalrammawia K, Buragohain A, Kakki B, Lalmuanpuii R, Pachuau Z, Vanlalhruaia J, Muthukumaran RB, Kumar NS, Jahau L, Sudarshan M, Yushin N, Nekhoroshkov P, Grozdov D, Sergeeva A, Zinicovscaia I. Macro-, micro-, and trace element distributions in areca nut, husk, and soil of northeast India. Environ Monit Assess 2021; 193:65. [PMID: 33449210 DOI: 10.1007/s10661-021-08859-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 01/07/2021] [Indexed: 06/12/2023]
Abstract
In areca nut and husk, 14 elements (As, Ca, Cd, Cl, Co, Cu, K, Mg, Mn, Na, Rb, Sb, and Zn) were determined, while 34 elements including rare earth elements were detected in the corresponding soil samples using instrumental neutron activation analysis and atomic absorption spectrometry methods, whereas the concentration levels of Hg in tested samples are negligible, perhaps, below the detection limits. No rare earth elements were detected in edible areca nut. The concentration levels of various essential elements and heavy elements such as As, Cd, and Cu present in areca nut are within the permissible levels, whereas Pb content is relatively higher than FAO/WHO's permissible levels. The order of bioaccumulation index for heavy metals in areca nut was Cd > Sb > Cu > Zn ≥ Mn ≥ Co > Pb ≥ As. Bioaccumulation index values are indicating that areca palm may not be able to accumulate other heavy elements in the edible areca nut, except for Cd. On the basis of pollution indices, Northeast Indian soil may be relatively unpolluted.
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Affiliation(s)
| | | | | | - Bomngam Kakki
- Department of Chemistry, Mizoram University, Aizawl, India
| | - Rebecca Lalmuanpuii
- Department of Chemistry, Mizoram University, Aizawl, India
- Department of Chemistry, Government Serchhip College, Serchhip, Mizoram, India
| | | | | | | | | | - Lalrintluanga Jahau
- Centre for Rural Development Research and Trinity Diagnostic Centre, Aizawl, Mizoram, India
| | - Mathummal Sudarshan
- UGC-DAE Consortium for Scientific Research, Kolkata Centre, Kolkata, 700106, India
| | - Nikita Yushin
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russian Federation, 141980
| | - Pavel Nekhoroshkov
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russian Federation, 141980
| | - Dmitrii Grozdov
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russian Federation, 141980
| | - Anastasiya Sergeeva
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russian Federation, 141980
| | - Inga Zinicovscaia
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russian Federation, 141980.
- Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering, 30 Reactorului Str. MG-6, Bucharest, Magurele, Romania.
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De Mandal S, Mathipi V, Muthukumaran RB, Gurusubramanian G, Lalnunmawii E, Kumar NS. Amplicon sequencing and imputed metagenomic analysis of waste soil and sediment microbiome reveals unique bacterial communities and their functional attributes. Environ Monit Assess 2019; 191:778. [PMID: 31784843 DOI: 10.1007/s10661-019-7879-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 10/10/2019] [Indexed: 06/10/2023]
Abstract
The discharge of solid and liquid waste from domestic, municipal, and hospital premises pollutes the soil and river ecosystems. However, the diversity and functions of the microbial communities present in these polluted environments are not well understood and may contain harmful microbial communities with specialized metabolic potential. In this present study, we adapted the Illumina sequencing technology to analyze microbial communities and their metabolic capabilities in polluted environments. A total of 1113884 sequences of v3-v4 hypervariable region of the 16S rRNA were obtained using Illumina sequencing and assigned to the corresponding taxonomical ranks using Greengenes databases. Proteobacteria and Bacteroidetes were dominantly present in all the four studied sites (solid waste dumping site (SWD); Chite river site (CHR), Turial river site (TUR), and Tuikual river site (TUKR)). It was found that the SWD was dominated by Firmicutes, Actinobacteria; CHR by Acidobacteria, Verrucomicrobia, Planctomycetes; TUR by Verrucomicrobia, Acidobacteria; and TUKR by Verrucomicrobia and Firmicutes, respectively. The dominant bacterial genus present in all samples was Acinetobacter, Flavobacterium, Prevotella, Corynebacterium, Comamonas, Bacteroides, Wautersiella, Cloacibacterium, Stenotrophomonas, Sphingobacterium, and Pseudomonas. Twenty-seven putative bacterial pathogens were identified from the contaminated sites belonging to Salmonella enterica, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus. Functional analysis showed a high representation of genes in the KEGG pathway involved in the metabolism of amino acids and carbohydrates and identified several genes associated with antibiotic resistance and xenobiotic degradation in these environments, which can be a serious problem for human health and environment. The results from this research will provide a new understanding of the possible management practices to minimize the spread of pathogenic microorganisms in the environment.
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Affiliation(s)
- Surajit De Mandal
- Department of Biotechnology, Mizoram University, Aizawl, Mizoram, 796004, India
- College of Agriculture, South China Agricultural University, Guangzhou, China
| | | | | | | | - Esther Lalnunmawii
- Department of Biotechnology, Mizoram University, Aizawl, Mizoram, 796004, India
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Hu CW, Chang YJ, Yen CC, Chen JL, Muthukumaran RB, Chao MR. 15N-labelled nitrite/nitrate tracer analysis by LC-MS/MS: Urinary and fecal excretion of nitrite/nitrate following oral administration to mice. Free Radic Biol Med 2019; 143:193-202. [PMID: 31398501 DOI: 10.1016/j.freeradbiomed.2019.08.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 07/30/2019] [Accepted: 08/06/2019] [Indexed: 12/21/2022]
Abstract
Determination of the modulation of nitrite and nitrate levels in biological samples usually poses a major challenge, owing to their high background concentrations. To effectively investigate the variation of nitrite/nitrate in vivo, in this study, we developed a15N-labelled nitrite/nitrate tracer analysis using LC-MS/MS following the derivatization with 2,3-diaminonaphthalene. This method allows for the determination of 15N-labelled nitrite/nitrate as 15N-2,3-naphthotriazole (15N-NAT) that can efficiently differentiate newly introduced nitrite/nitrate from the background nitrite/nitrate in biological matrices. We also investigated the contribution of background 14N-NAT isotopomers to 15N-NAT, which has long been overlooked in the literature. Our results indicated that the contribution of background 14N-NAT isotopomers to 15N-NAT is significant. Such contribution is constant (~2.2% under positive ion mode and 1.1% under negative ion mode), and does not depend upon the concentration of 14N-NAT or the sample matrix measured. An equation has been therefore developed, for the first time, to correct the contribution of background 14N-NAT isotopomers to 15N-NAT. With the proposed 15N-labelled nitrite/nitrate tracer analysis, the amount and percentage distribution of 15NO2- and 15NO3-, both in urine and feces, after oral administration of 15N-labelled nitrite/nitrate are clearly demonstrated. The excretions of 15NO2- and 15NO3- were significantly increased with the increasing dose implying that the dietary nitrite/nitrate intake is an important source in urine/feces. The present method allows for the simple, reliable and accurate quantification of 15NO2- and 15NO3-, and it should also be useful to trace the biotransformation of nitrite and nitrate in vivo.
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Affiliation(s)
- Chiung-Wen Hu
- Department of Public Health, Chung Shan Medical University, Taichung, 402, Taiwan
| | - Yuan-Jhe Chang
- Department of Occupational Safety and Health, Chung Shan Medical University, Taichung, 402, Taiwan
| | - Cheng-Chieh Yen
- Department of Occupational Safety and Health, Chung Shan Medical University, Taichung, 402, Taiwan
| | - Jian-Lian Chen
- School of Pharmacy, China Medical University, Taichung, 404, Taiwan
| | | | - Mu-Rong Chao
- Department of Occupational Safety and Health, Chung Shan Medical University, Taichung, 402, Taiwan; Department of Occupational Medicine, Chung Shan Medical University Hospital, Taichung, 402, Taiwan.
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De Mandal S, Singh SS, Muthukumaran RB, Thanzami K, Kumar V, Kumar NS. Metagenomic analysis and the functional profiles of traditional fermented pork fat 'sa-um' of Northeast India. AMB Express 2018; 8:163. [PMID: 30298308 PMCID: PMC6175732 DOI: 10.1186/s13568-018-0695-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 10/03/2018] [Indexed: 02/01/2023] Open
Abstract
Fermented pork fat (sa-um) is traditionally and extensively consumed in Northeast Indian region for several decades. However, no scientific reports are available regarding its nutritional value as well as its potential health risks. The objective of this work was essentially the characterization of sa-um using a polyphasic approach, viz., physicochemical, electrospray ionization-mass spectrometry (ESI+-MS) and metagenomic analysis in order to gain an understanding of the nutrient contents and microbial population diversity. On a dry weight basis, about 91% fat, 2% carbohydrate and 0.70% protein were present. ESI+-MS analysis of sa-um revealed the presence of various polar and neutral lipids corresponding to monoacylglyceride, diacylglyceride and triacylglyceride species. The dominant bacterial phyla were Firmicutes, Proteobacteria and Bacteroidetes. A total of 72 bacterial genera were identified, largely abundant with Clostridium species including C. butyricum, C. citroniae, C. methylpentosum, C. perfringens, C. saccharogumia and C. tetani. The imputed functional profiles of bacterial communities were predominantly involved in energy, carbohydrate and amino acid metabolisms. Furthermore, this study deduces the presence of pro-inflammatory molecules as well as antibiotic resistance genes associated with the bacterial families such as Bacillaceae, Bacteroidaceae, Clostridiaceae, Corynebacteriaceae and Enterobacteriaceae which might be a major health concern for the sa-um consuming population.
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Affiliation(s)
- Surajit De Mandal
- Department of Biotechnology, Mizoram University, Aizawl, Mizoram 796004 India
| | | | | | - Kawl Thanzami
- Dept of Pharmacy, Regional Institute of Paramedical and Nursing Sciences, Aizawl, Mizoram 796017 India
| | - Vinod Kumar
- Biotech Consortium India Ltd, Anuvrat Bhawan, Deen Dayal Upadhyaya Marg, New Delhi, 110002 India
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Abstract
Isolation of DNA from blood and buccal swabs in adequate quantities is an integral part of forensic research and analysis. The present study was performed to determine the quality and the quantity of DNA extracted from four commonly available samples and to estimate the time duration of the ensuing PCR amplification. Here, we demonstrate that hair and urine samples can also become an alternate source for reliably obtaining a small quantity of PCR-ready DNA. We developed a rapid, cost-effective, and noninvasive method of sample collection and simple DNA extraction from buccal swabs, urine, and hair using the phenol-chloroform method. Buccal samples were subjected to DNA extraction, immediately or after refrigeration (4-6°C) for 3 days. The purity and the concentration of the extracted DNA were determined spectrophotometerically, and the adequacy of DNA extracts for the PCR-based assay was assessed by amplifying a 1030-bp region of the mitochondrial D-loop. Although DNA from all the samples was suitable for PCR, the blood and hair samples provided a good quality DNA for restriction analysis of the PCR product compared with the buccal swab and urine samples. In the present study, hair samples proved to be a good source of genomic DNA for PCR-based methods. Hence, DNA of hair samples can also be used for the genomic disorder analysis in addition to the forensic analysis as a result of the ease of sample collection in a noninvasive manner, lower sample volume requirements, and good storage capability.
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Samuel L, Lalrotluanga, Muthukumaran RB, Gurusubramanian G, Senthilkumar N. Larvicidal activity of Ipomoea cairica (L.) Sweet and Ageratina adenophora (Spreng.) King & H. Rob. plant extracts against arboviral and filarial vector, Culex quinquefasciatus Say (Diptera: Culicidae). Exp Parasitol 2014; 141:112-21. [DOI: 10.1016/j.exppara.2014.03.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 03/13/2014] [Accepted: 03/13/2014] [Indexed: 10/25/2022]
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Muthukumaran RB, Grzyska PK, Hausinger RP, McCracken J. Probing the Iron−Substrate Orientation for Taurine/α-Ketoglutarate Dioxygenase Using Deuterium Electron Spin Echo Envelope Modulation Spectroscopy. Biochemistry 2007; 46:5951-9. [PMID: 17469855 DOI: 10.1021/bi700562t] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The structural relationship between substrate taurine and the non-heme Fe(II) center of taurine/alpha-ketoglutarate (alphaKG) dioxygenase (TauD) was measured using electron spin echo envelope modulation (ESEEM) spectroscopy. Studies were conducted on TauD samples treated with NO, cosubstrate alphaKG, and either protonated or specifically deuterated taurine. Stimulated echo ESEEM data were divided to eliminate interference from 1H and 14N modulations and accentuate modulations from 2H. For taurine that was deuterated at the C1 position (adjacent to the sulfonate group), 2H ESEEM spectra show features that arise from dipole-dipole and deuterium nuclear quadrupole interactions from a single deuteron. Parallel measurements taken for taurine deuterated at both C1 and C2 show an additional ESEEM feature at the deuterium Larmor frequency. Analysis of these data at field positions ranging from g = 4 to g = 2 have allowed us to define the orientation of substrate taurine with respect to the magnetic axes of the Fe(II)-NO, S = 3/2, paramagnetic center. These results are discussed in terms of previous X-ray crystallographic studies and the proposed catalytic mechanism for this family of enzymes.
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Ryle MJ, Liu A, Muthukumaran RB, Ho RYN, Koehntop KD, McCracken J, Que L, Hausinger RP. O2- and alpha-ketoglutarate-dependent tyrosyl radical formation in TauD, an alpha-keto acid-dependent non-heme iron dioxygenase. Biochemistry 2003; 42:1854-62. [PMID: 12590572 DOI: 10.1021/bi026832m] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Taurine/alpha-ketoglutarate dioxygenase (TauD), a non-heme mononuclear Fe(II) oxygenase, liberates sulfite from taurine in a reaction that requires the oxidative decarboxylation of alpha-ketoglutarate (alphaKG). The lilac-colored alphaKG-Fe(II)TauD complex (lambda(max) = 530 nm; epsilon(530) = 140 M(-)(1) x cm(-)(1)) reacts with O(2) in the absence of added taurine to generate a transient yellow species (lambda(max) = 408 nm, minimum of 1,600 M(-)(1) x cm(-)(1)), with apparent first-order rate constants for formation and decay of approximately 0.25 s(-)(1) and approximately 0.5 min(-)(1), that transforms to yield a greenish brown chromophore (lambda(max) = 550 nm, 700 M(-)(1) x cm(-)(1)). The latter feature exhibits resonance Raman vibrations consistent with an Fe(III) catecholate species presumed to arise from enzymatic self-hydroxylation of a tyrosine residue. Significantly, (18)O labeling studies reveal that the added oxygen atom derives from solvent rather than from O(2). The transient yellow species, identified as a tyrosyl radical on the basis of EPR studies, is formed after alphaKG decomposition. Substitution of two active site tyrosine residues (Tyr73 and Tyr256) by site-directed mutagenesis identified Tyr73 as the likely site of formation of both the tyrosyl radical and the catechol-associated chromophore. The involvement of the tyrosyl radical in catalysis is excluded on the basis of the observed activity of the enzyme variants. We suggest that the Fe(IV) oxo species generally proposed (but not yet observed) as an intermediate for this family of enzymes reacts with Tyr73 when substrate is absent to generate Fe(III) hydroxide (capable of exchanging with solvent) and the tyrosyl radical, with the latter species participating in a multistep TauD self-hydroxylation reaction.
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Affiliation(s)
- Matthew J Ryle
- Department of Microbiology, Michigan State University, East Lansing, Michigan 48824, USA
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Ranganathan D, Vaish NK, Chandramouli GVR, Varghese B, Muthukumaran RB, Manoharan PT. Crystal Structure of [Aib-COCO-Aib]Cu2: A Unique Example of Modular Self-Assembly. J Am Chem Soc 2002. [DOI: 10.1021/ja00110a023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Bouchev VF, Furdui CM, Menon S, Muthukumaran RB, Ragsdale SW, McCracken J. ENDOR Studies of Pyruvate:Ferredoxin Oxidoreductase Reaction Intermediates. J Am Chem Soc 1999. [DOI: 10.1021/ja984057l] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Vladimir F. Bouchev
- Contribution from the Department of Chemistry, Michigan State University, East Lansing, Michigan 48824 and Department of Biochemistry, Beadle Center, University of Nebraska, Lincoln, Nebraska 68588-0664
| | - Cristina M. Furdui
- Contribution from the Department of Chemistry, Michigan State University, East Lansing, Michigan 48824 and Department of Biochemistry, Beadle Center, University of Nebraska, Lincoln, Nebraska 68588-0664
| | - Saurabh Menon
- Contribution from the Department of Chemistry, Michigan State University, East Lansing, Michigan 48824 and Department of Biochemistry, Beadle Center, University of Nebraska, Lincoln, Nebraska 68588-0664
| | - Rajendra Bose Muthukumaran
- Contribution from the Department of Chemistry, Michigan State University, East Lansing, Michigan 48824 and Department of Biochemistry, Beadle Center, University of Nebraska, Lincoln, Nebraska 68588-0664
| | - Stephen W. Ragsdale
- Contribution from the Department of Chemistry, Michigan State University, East Lansing, Michigan 48824 and Department of Biochemistry, Beadle Center, University of Nebraska, Lincoln, Nebraska 68588-0664
| | - John McCracken
- Contribution from the Department of Chemistry, Michigan State University, East Lansing, Michigan 48824 and Department of Biochemistry, Beadle Center, University of Nebraska, Lincoln, Nebraska 68588-0664
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