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Title: Chromate Binding and Removal by the Molybdate-Binding Protein ModA

Authors:
 [1];  [1];  [1];  [1];  [1]
  1. Department of Chemistry, University of Chicago, 929 East 57th Street Chicago IL 60637 USA
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1400604
Grant/Contract Number:
FG02-07ER15865
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
ChemBioChem: a European journal of chemical biology
Additional Journal Information:
Journal Volume: 18; Journal Issue: 7; Related Information: CHORUS Timestamp: 2017-10-20 15:00:39; Journal ID: ISSN 1439-4227
Publisher:
Wiley Blackwell (John Wiley & Sons)
Country of Publication:
France
Language:
English

Citation Formats

Karpus, Jason, Bosscher, Michael, Ajiboye, Ifedayo, Zhang, Liang, and He, Chuan. Chromate Binding and Removal by the Molybdate-Binding Protein ModA. France: N. p., 2017. Web. doi:10.1002/cbic.201700051.
Karpus, Jason, Bosscher, Michael, Ajiboye, Ifedayo, Zhang, Liang, & He, Chuan. Chromate Binding and Removal by the Molybdate-Binding Protein ModA. France. doi:10.1002/cbic.201700051.
Karpus, Jason, Bosscher, Michael, Ajiboye, Ifedayo, Zhang, Liang, and He, Chuan. Mon . "Chromate Binding and Removal by the Molybdate-Binding Protein ModA". France. doi:10.1002/cbic.201700051.
@article{osti_1400604,
title = {Chromate Binding and Removal by the Molybdate-Binding Protein ModA},
author = {Karpus, Jason and Bosscher, Michael and Ajiboye, Ifedayo and Zhang, Liang and He, Chuan},
abstractNote = {},
doi = {10.1002/cbic.201700051},
journal = {ChemBioChem: a European journal of chemical biology},
number = 7,
volume = 18,
place = {France},
year = {Mon Mar 06 00:00:00 EST 2017},
month = {Mon Mar 06 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1002/cbic.201700051

Citation Metrics:
Cited by: 1work
Citation information provided by
Web of Science

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  • The objective was to prepare a reagent to remove Cr(VI) ions from wastewater and separate Cr(VI) from other ions that might interfere with its determination. 4-Aminobenzoic acid, (1-(4-pyridinyl)-2-(1-piperdinyl))ethyl ester, was synthesized and tested to determine its ability to selectively precipitate anions. Fifty-seven common anions were tested. The reagent reacted most readily with the oxyanions of Group VIB and vanadium. The precursor alcohol, 1-(4-pyridinyl)-2-(piperidinyl)ethanol, and the unsubstituted benzoate ester, 1-(4-pyridinyl)-2-(piperidinyl)ethyl benzoate, were also tested. Dissolution of the precipitates in a strong base followed by a methylene chloride wash removes the organic reagent and frees the anions for further analysis.
  • molA (HI1472) from H. influenzae encodes a periplasmic binding protein (PBP) that delivers substrate to the ABC transporter MolB{sub 2}C{sub 2} (formerly HI1470/71). The structures of MolA with molybdate and tungstate in the binding pocket were solved to 1.6 and 1.7 {angstrom} resolution, respectively. The MolA-binding protein binds molybdate and tungstate, but not other oxyanions such as sulfate and phosphate, making it the first class III molybdate-binding protein structurally solved. The {approx}100 {mu}M binding affinity for tungstate and molybdate is significantly lower than observed for the class II ModA molybdate-binding proteins that have nanomolar to low micromolar affinity for molybdate.more » The presence of two molybdate loci in H. influenzae suggests multiple transport systems for one substrate, with molABC constituting a low-affinity molybdate locus.« less
  • The molybdate-binding protein (ModA) from X. axonopodis pv. citri was crystallized with sodium molybdate in the presence of PEG or sulfate. The crystal diffracted to a maximum resolution of 1.7 Å and belongs to the orthorhombic space group C222{sub 1,} with unit-cell parameters a = 68.15, b = 172.14, c = 112.04 Å. Xanthomonas axonopodis pv. citri ModA protein is the ABC periplasmic binding component responsible for the capture of molybdate. The protein was crystallized with sodium molybdate using the hanging-drop vapour-diffusion method in the presence of PEG or sulfate. X-ray diffraction data were collected to a maximum resolution ofmore » 1.7 Å using synchrotron radiation. The crystal belongs to the orthorhombic space group C222{sub 1}, with unit-cell parameters a = 68.15, b = 172.14, c = 112.04 Å. The crystal structure was solved by molecular-replacement methods and structure refinement is in progress.« less
  • The surface-enhanced Raman scattering (SERS) excitation profiles of chromate, molybdate, and tungstate ions on colloidal silver were obtained by using excitation wavelengths between 457.9 and 676.4 nm. The intensity of the strongest SERS band between 800 and 900 cm/sup -1/, assignable to nu/sub s/(M-O), was in each case referenced to the 1020-cm/sup -1/ band of the internal standard, methanol, in silver hydrosols. These relative SERS intensities were compared against similar intensity ratios for each oxo anion in solution and then appropriately scaled for the concentration of MO/sub 4//sup 2 -/ in solution and on the surface of the silver particlesmore » in the sols. Peak SERS enhancements occurred at 560 nm for CrO/sub 4//sup 2 -/ and at 600 nm for both MoO/sub 4//sup 2 -/ and WO/sub 4//sup 2 -/. The latter peak positions matched the secondary absorption band maxima that originate from aggregates of silver particles in the sols. The numerical values of the SERS enhancements were 5 x 10/sup 4/-l x 10/sup 5/ for CrO/sub 4//sup 2 -/, 9 x 10/sup 5/ for MoO/sub 4//sup 2 -/, and about 2 x 10/sup 5/ for WO/sub 4//sup 2 -/ on colloidal silver. The somewhat lower SERS enhancements for the chromophoric adsorbate, CrO/sub 4//sup 2 -/, which adsorbs maximally at 370 nm in aqueous solution, are attributed to a lower degree of aggregation for the sols with added CrO/sub 4//sup 2 -/, rather than to partial quenching of its resonant excited state on the heavy metal (silver) surface. 34 references, 4 figures, 5 tables.« less