DOI: 10.1111/j.1432-1033.1974.tb03646.x. Electron‐Paramagnetic‐Resonance Studies on Nitrogenase

Electron‐Paramagnetic‐Resonance Studies on Nitrogenase

10.1111/j.1432-1033.1974.tb03646.x

Crossref journal-article

Wiley

European Journal of Biochemistry (311)

Abstract

The oxidation‐reduction properties of azoferredoxin, molybdoferredoxin, and the inactive species of molybdoferredoxin, all iron‐sulfur proteins purified from Clostridium pasteurianum, were studied by potentiometry combined with electron paramagnetic resonance spectroscopy at low temperature. The technique, evaluated with spinach ferredoxin for which a midpoint potential of ‐446 mV was determined (pH 7.9, showed that azoferredoxin has a midpoint potential of ‐294 ± 20 mV (pH 7.5). In the presence of MgATP2−, azoferredoxin undergoes a negative shift of 110 mV in its oxidation‐reduction potential. The resulting potential of approximately ‐400 mV is likely to be effective under physiological conditions. The potential shift is consistent with a proposed conformational change of the protein caused by the binding of two molecules of ATP to the protein (dimer). Molybdoferredoxin and its inactive species, which has an incomplete iron‐sulfur and molybdenum centre, have midpoint potentials of approximately −20 mV and −395 mV, respectively, both at pH 7.5. All nitrogenase proteins are characterized by the transfer of one electron per redox step.Kinetic studies of the reduction of azoferredoxin and molybdoferredoxin by dithionite gave half times of <10 ms and 3–5 min, respectively. Hence, the latter process must be excluded from being part of the physiological reaction. The complex formation of ATP with azoferredoxin is a relatively slow process, which is markedly accelerated by molybdoferredoxin in the reconstituted nitrogenase system. Changes in the electron paramagnetic resonance signals of reconstituted nitrogenase were followed by a rapid‐freeze technique as a function of mixing sequence and ratio of the two proteins. The observed signal changes were independent of the mixing sequence. The steady‐state level of the molybdoferredoxin signal was also independent of the ratio of the two proteins and was less than 15% of the original resonance. The results indicate that the role of the azoferredoxin · ATP complex may not be confined solely to the function of an electron carrier for the nitrogenase reaction.

Bibliography

ZUMFT, W. G., MORTENSON, L. E., & PALMER, G. (1974). ElectronâParamagneticâResonance Studies on Nitrogenase. European Journal of Biochemistry, 46(3), 525â535. Portico.

Authors 3

Walter G. ZUMFT (first)
Leonard E. MORTENSON (additional)
Graham PALMER (additional)

References 31 Referenced 133

10.1016/0006-291X(72)90887-X
10.1016/0005-2728(73)90047-9
10.1016/0005-2728(68)90188-6
10.1016/S0021-9258(18)91743-6
10.1016/0006-291X(73)91475-7
10.1042/bj1330405
10.1016/0006-291X(73)90177-0
10.1111/j.1432-1033.1973.tb02852.x
10.1016/0005-2728(73)90048-0
10.1016/0003-9861(70)90162-1
{'key': 'e_1_2_3_12_2', 'first-page': '71', 'volume': '81', 'author': 'Mortenson L. E.', 'year': '1964', 'journal-title': 'Biochim. Biophys. Acta'} / Biochim. Biophys. Acta by Mortenson L. E. (1964)
10.1016/0003-9861(72)90452-3
10.1073/pnas.69.11.3142
10.1016/S0021-9258(18)96988-7
10.1016/0006-291X(66)90733-9
10.1016/0006-291X(69)90569-5
{'key': 'e_1_2_3_18_2', 'first-page': '57', 'volume': '117', 'author': 'Schreiner E.', 'year': '1925', 'journal-title': 'J. Phys. Chem.'} / J. Phys. Chem. by Schreiner E. (1925)
{'key': 'e_1_2_3_19_2', 'volume-title': 'Oxidation‐Reduction Potentials of Organic Systems', 'author': 'Clark W. M.', 'year': '1960'} / Oxidation‐Reduction Potentials of Organic Systems by Clark W. M. (1960)
10.1016/0005-2728(73)90103-5
10.1016/S0021-9258(19)52451-6
10.3109/00365515309094189
Ballou D. P.&Palmer G.(1974)Anal. Chem. submitted.
Mathews R. Charlton S. Sands R. H.&Palmer G.(1974)J. Biol. Chem. submitted.
10.1042/bj1300641
10.1042/bj1350331
10.1016/0005-2744(73)90024-7
10.1016/0005-2728(68)90005-4
10.1073/pnas.69.8.2263
10.1007/BFb0036785
10.1042/bst0010001
{'key': 'e_1_2_3_32_2', 'first-page': '261', 'volume-title': 'Non‐Heme Iron Proteins', 'author': 'Bulen W. A.', 'year': '1965'} / Non‐Heme Iron Proteins by Bulen W. A. (1965)

Dates

Type	When
Created	20 years, 6 months ago (March 4, 2005, 8:40 a.m.)
Deposited	1 year, 9 months ago (Nov. 22, 2023, 4:41 p.m.)
Indexed	1 year, 1 month ago (July 18, 2024, 3:11 p.m.)
Issued	51 years, 1 month ago (Aug. 1, 1974)
Published	51 years, 1 month ago (Aug. 1, 1974)
Published Online	20 years, 6 months ago (March 3, 2005)
Published Print	51 years, 1 month ago (Aug. 1, 1974)

Funders 0

None

BibTeX

@article{ZUMFT_1974, title={Electron‐Paramagnetic‐Resonance Studies on Nitrogenase: Investigation of the Oxidation‐Reduction Behaviour of Azoferredoxin and Molybdoferredoxin with Potentiometric and Rapid‐Freeze Techniques}, volume={46}, ISSN={1432-1033}, url={http://dx.doi.org/10.1111/j.1432-1033.1974.tb03646.x}, DOI={10.1111/j.1432-1033.1974.tb03646.x}, number={3}, journal={European Journal of Biochemistry}, publisher={Wiley}, author={ZUMFT, Walter G. and MORTENSON, Leonard E. and PALMER, Graham}, year={1974}, month=aug, pages={525–535} }

JSON

{
  "indexed": {
    "date-parts": [
      [
        2024,
        7,
        18
      ]
    ],
    "date-time": "2024-07-18T19:11:36Z",
    "timestamp": 1721329896758
  },
  "reference-count": 31,
  "publisher": "Wiley",
  "issue": "3",
  "license": [
    {
      "start": {
        "date-parts": [
          [
            2005,
            3,
            3
          ]
        ],
        "date-time": "2005-03-03T00:00:00Z",
        "timestamp": 1109808000000
      },
      "content-version": "vor",
      "delay-in-days": 11172,
      "URL": "http://onlinelibrary.wiley.com/termsAndConditions#vor"
    }
  ],
  "content-domain": {
    "domain": [],
    "crossmark-restriction": false
  },
  "published-print": {
    "date-parts": [
      [
        1974,
        8
      ]
    ]
  },
  "abstract": "<jats:p>The oxidation\u2010reduction properties of azoferredoxin, molybdoferredoxin, and the inactive species of molybdoferredoxin, all iron\u2010sulfur proteins purified from <jats:italic>Clostridium pasteurianum</jats:italic>, were studied by potentiometry combined with electron paramagnetic resonance spectroscopy at low temperature. The technique, evaluated with spinach ferredoxin for which a midpoint potential of \u2010446 mV was determined (pH 7.9, showed that azoferredoxin has a midpoint potential of \u2010294 \u00b1 20 mV (pH 7.5). In the presence of MgATP<jats:sup>2\u2212</jats:sup>, azoferredoxin undergoes a negative shift of 110 mV in its oxidation\u2010reduction potential. The resulting potential of approximately \u2010400 mV is likely to be effective under physiological conditions. The potential shift is consistent with a proposed conformational change of the protein caused by the binding of two molecules of ATP to the protein (dimer). Molybdoferredoxin and its inactive species, which has an incomplete iron\u2010sulfur and molybdenum centre, have midpoint potentials of approximately \u221220 mV and \u2212395 mV, respectively, both at pH 7.5. All nitrogenase proteins are characterized by the transfer of one electron per redox step.</jats:p><jats:p>Kinetic studies of the reduction of azoferredoxin and molybdoferredoxin by dithionite gave half times of &lt;10 ms and 3\u20135 min, respectively. Hence, the latter process must be excluded from being part of the physiological reaction. The complex formation of ATP with azoferredoxin is a relatively slow process, which is markedly accelerated by molybdoferredoxin in the reconstituted nitrogenase system. Changes in the electron paramagnetic resonance signals of reconstituted nitrogenase were followed by a rapid\u2010freeze technique as a function of mixing sequence and ratio of the two proteins. The observed signal changes were independent of the mixing sequence. The steady\u2010state level of the molybdoferredoxin signal was also independent of the ratio of the two proteins and was less than 15% of the original resonance. The results indicate that the role of the azoferredoxin \u00b7 ATP complex may not be confined solely to the function of an electron carrier for the nitrogenase reaction.</jats:p>",
  "DOI": "10.1111/j.1432-1033.1974.tb03646.x",
  "type": "journal-article",
  "created": {
    "date-parts": [
      [
        2005,
        3,
        4
      ]
    ],
    "date-time": "2005-03-04T13:40:01Z",
    "timestamp": 1109943601000
  },
  "page": "525-535",
  "source": "Crossref",
  "is-referenced-by-count": 133,
  "title": "Electron\u2010Paramagnetic\u2010Resonance Studies on Nitrogenase",
  "prefix": "10.1111",
  "volume": "46",
  "author": [
    {
      "given": "Walter G.",
      "family": "ZUMFT",
      "sequence": "first",
      "affiliation": []
    },
    {
      "given": "Leonard E.",
      "family": "MORTENSON",
      "sequence": "additional",
      "affiliation": []
    },
    {
      "given": "Graham",
      "family": "PALMER",
      "sequence": "additional",
      "affiliation": []
    }
  ],
  "member": "311",
  "published-online": {
    "date-parts": [
      [
        2005,
        3,
        3
      ]
    ]
  },
  "reference": [
    {
      "key": "e_1_2_3_2_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0006-291X(72)90887-X"
    },
    {
      "key": "e_1_2_3_3_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0005-2728(73)90047-9"
    },
    {
      "key": "e_1_2_3_4_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0005-2728(68)90188-6"
    },
    {
      "key": "e_1_2_3_5_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/S0021-9258(18)91743-6"
    },
    {
      "key": "e_1_2_3_6_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0006-291X(73)91475-7"
    },
    {
      "key": "e_1_2_3_7_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1042/bj1330405"
    },
    {
      "key": "e_1_2_3_8_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0006-291X(73)90177-0"
    },
    {
      "key": "e_1_2_3_9_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1111/j.1432-1033.1973.tb02852.x"
    },
    {
      "key": "e_1_2_3_10_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0005-2728(73)90048-0"
    },
    {
      "key": "e_1_2_3_11_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0003-9861(70)90162-1"
    },
    {
      "key": "e_1_2_3_12_2",
      "first-page": "71",
      "volume": "81",
      "author": "Mortenson L. E.",
      "year": "1964",
      "journal-title": "Biochim. Biophys. Acta"
    },
    {
      "key": "e_1_2_3_13_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0003-9861(72)90452-3"
    },
    {
      "key": "e_1_2_3_14_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1073/pnas.69.11.3142"
    },
    {
      "key": "e_1_2_3_15_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/S0021-9258(18)96988-7"
    },
    {
      "key": "e_1_2_3_16_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0006-291X(66)90733-9"
    },
    {
      "key": "e_1_2_3_17_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0006-291X(69)90569-5"
    },
    {
      "key": "e_1_2_3_18_2",
      "first-page": "57",
      "volume": "117",
      "author": "Schreiner E.",
      "year": "1925",
      "journal-title": "J. Phys. Chem."
    },
    {
      "key": "e_1_2_3_19_2",
      "volume-title": "Oxidation\u2010Reduction Potentials of Organic Systems",
      "author": "Clark W. M.",
      "year": "1960"
    },
    {
      "key": "e_1_2_3_20_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0005-2728(73)90103-5"
    },
    {
      "key": "e_1_2_3_21_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/S0021-9258(19)52451-6"
    },
    {
      "key": "e_1_2_3_22_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.3109/00365515309094189"
    },
    {
      "key": "e_1_2_3_23_2",
      "unstructured": "Ballou D. P.&Palmer G.(1974)Anal. Chem. submitted."
    },
    {
      "key": "e_1_2_3_24_2",
      "unstructured": "Mathews R. Charlton S. Sands R. H.&Palmer G.(1974)J. Biol. Chem. submitted."
    },
    {
      "key": "e_1_2_3_25_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1042/bj1300641"
    },
    {
      "key": "e_1_2_3_26_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1042/bj1350331"
    },
    {
      "key": "e_1_2_3_27_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0005-2744(73)90024-7"
    },
    {
      "key": "e_1_2_3_28_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0005-2728(68)90005-4"
    },
    {
      "key": "e_1_2_3_29_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1073/pnas.69.8.2263"
    },
    {
      "key": "e_1_2_3_30_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1007/BFb0036785"
    },
    {
      "key": "e_1_2_3_31_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1042/bst0010001"
    },
    {
      "key": "e_1_2_3_32_2",
      "first-page": "261",
      "volume-title": "Non\u2010Heme Iron Proteins",
      "author": "Bulen W. A.",
      "year": "1965"
    }
  ],
  "container-title": "European Journal of Biochemistry",
  "original-title": [],
  "language": "en",
  "link": [
    {
      "URL": "https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1432-1033.1974.tb03646.x",
      "content-type": "unspecified",
      "content-version": "vor",
      "intended-application": "text-mining"
    },
    {
      "URL": "https://febs.onlinelibrary.wiley.com/doi/pdf/10.1111/j.1432-1033.1974.tb03646.x",
      "content-type": "unspecified",
      "content-version": "vor",
      "intended-application": "similarity-checking"
    }
  ],
  "deposited": {
    "date-parts": [
      [
        2023,
        11,
        22
      ]
    ],
    "date-time": "2023-11-22T21:41:23Z",
    "timestamp": 1700689283000
  },
  "score": 1,
  "resource": {
    "primary": {
      "URL": "https://febs.onlinelibrary.wiley.com/doi/10.1111/j.1432-1033.1974.tb03646.x"
    }
  },
  "subtitle": [
    "Investigation of the Oxidation\u2010Reduction Behaviour of Azoferredoxin and Molybdoferredoxin with Potentiometric and Rapid\u2010Freeze Techniques"
  ],
  "short-title": [],
  "issued": {
    "date-parts": [
      [
        1974,
        8
      ]
    ]
  },
  "references-count": 31,
  "journal-issue": {
    "issue": "3",
    "published-print": {
      "date-parts": [
        [
          1974,
          8
        ]
      ]
    }
  },
  "alternative-id": [
    "10.1111/j.1432-1033.1974.tb03646.x"
  ],
  "URL": "http://dx.doi.org/10.1111/j.1432-1033.1974.tb03646.x",
  "relation": {},
  "ISSN": [
    "0014-2956",
    "1432-1033"
  ],
  "subject": [],
  "container-title-short": "European Journal of Biochemistry",
  "published": {
    "date-parts": [
      [
        1974,
        8
      ]
    ]
  }
}