Aggregation states of phosphoribulokinase (PRK) in vivo

Porter, M A; Hartman, F C

Title: Aggregation states of phosphoribulokinase (PRK) in vivo

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Abstract

Spinach PRK, extracted from either light- or dark-harvested tissue (LHT or DHT) in the presence of DTT, has a M{sub r} of 90 kDa and is fully active. Consistent with an earlier study extraction of LHT in the absence of DTT results in two forms of inactive PRK, M{sub r} 90 kDa (LMW) and M{sub r}> 550 kDa (HMW). If 400 mM (NH{sub 4}){sub 2}SO{sub 4} without DTT is included during extraction, the active LMW predominates implicating it as the major, functional form in vivo during periods of illumination. Either high- or low-sale extraction of DHT reveals mostly HMW; prolonged incubation of the high-salt extract causes disaggregation of LMW without activation. These data suggest that the dark form of PRK in vivo is an aggregate, formed by either self-association or by interactions with other proteins. Salt-induced disaggregation of HMW is inconsistent with intermolecular disulfides crosslinking the aggregated PRK; therefore, oxidation-induced conformational changes must promote aggregation.

Authors:

Porter, M A; Hartman, F C ^[1]

Oak Ridge National Lab, TN (USA)

Publication Date:: Sat Apr 01 00:00:00 EST 1989

OSTI Identifier:: 6651439

Resource Type:: Journal Article

Journal Name:: Plant Physiology, Supplement; (USA)

Additional Journal Information:: Journal Volume: 89:4; Journal ID: ISSN 0079-2241

Country of Publication:: United States

Language:: English

Subject:: 59 BASIC BIOLOGICAL SCIENCES; PHOSPHOTRANSFERASES; ENZYME ACTIVITY; IN VIVO; REDOX REACTIONS; SPINACH; CHEMICAL REACTIONS; ENZYMES; FOOD; MAGNOLIOPHYTA; MAGNOLIOPSIDA; PHOSPHORUS-GROUP TRANSFERASES; PLANTS; TRANSFERASES; VEGETABLES; 550200* - Biochemistry

Citation Formats


                    Porter, M A, and Hartman, F C. Aggregation states of phosphoribulokinase (PRK) in vivo.  United States: N. p., 1989. 
        Web.

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                    Porter, M A, & Hartman, F C. Aggregation states of phosphoribulokinase (PRK) in vivo.  United States.

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                    Porter, M A, and Hartman, F C. 1989.  
        "Aggregation states of phosphoribulokinase (PRK) in vivo".  United States.

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@article{osti_6651439,

  title        = {Aggregation states of phosphoribulokinase (PRK) in vivo},

  author       = {Porter, M A and Hartman, F C},

  abstractNote = {Spinach PRK, extracted from either light- or dark-harvested tissue (LHT or DHT) in the presence of DTT, has a M{sub r} of 90 kDa and is fully active. Consistent with an earlier study extraction of LHT in the absence of DTT results in two forms of inactive PRK, M{sub r} 90 kDa (LMW) and M{sub r}> 550 kDa (HMW). If 400 mM (NH{sub 4}){sub 2}SO{sub 4} without DTT is included during extraction, the active LMW predominates implicating it as the major, functional form in vivo during periods of illumination. Either high- or low-sale extraction of DHT reveals mostly HMW; prolonged incubation of the high-salt extract causes disaggregation of LMW without activation. These data suggest that the dark form of PRK in vivo is an aggregate, formed by either self-association or by interactions with other proteins. Salt-induced disaggregation of HMW is inconsistent with intermolecular disulfides crosslinking the aggregated PRK; therefore, oxidation-induced conformational changes must promote aggregation.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/6651439},
  journal      = {Plant Physiology, Supplement; (USA)},

  issn         = {0079-2241},

  number       = ,

  volume       = 89:4,

  place        = {United States},

  year         = {Sat Apr 01 00:00:00 EST 1989},

  month        = {Sat Apr 01 00:00:00 EST 1989}

}

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