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Zayas-Santiago CC, Rivas-Ubach A, Kuo LJ, Ward ND, Zimmerman RC. Metabolic Profiling Reveals Biochemical Pathways Responsible for Eelgrass Response to Elevated CO 2 and Temperature. Sci Rep 2020; 10:4693. [PMID: 32170204 PMCID: PMC7070064 DOI: 10.1038/s41598-020-61684-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 02/25/2020] [Indexed: 11/17/2022] Open
Abstract
As CO2 levels in Earth’s atmosphere and oceans steadily rise, varying organismal responses may produce ecological losers and winners. Increased ocean CO2 can enhance seagrass productivity and thermal tolerance, providing some compensation for climate warming. However, the metabolic shifts driving the positive response to elevated CO2 by these important ecosystem engineers remain unknown. We analyzed whole-plant performance and metabolic profiles of two geographically distinct eelgrass (Zostera marina L.) populations in response to CO2 enrichment. In addition to enhancing overall plant size, growth and survival, CO2 enrichment increased the abundance of Calvin Cycle and nitrogen assimilation metabolites while suppressing the abundance of stress-related metabolites. Overall metabolome differences between populations suggest that some eelgrass phenotypes may be better suited than others to cope with an increasingly hot and sour sea. Our results suggest that seagrass populations will respond variably, but overall positively, to increasing CO2 concentrations, generating negative feedbacks to climate change.
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Affiliation(s)
- Carmen C Zayas-Santiago
- Department of Ocean, Earth & Atmospheric Sciences, Old Dominion University, Norfolk, VA, 23429, USA.
| | - Albert Rivas-Ubach
- Environmental Molecular Sciences Division, Pacific Northwest National Laboratory, 3335 Innovation Boulevard, Richland, WA, 99352, USA
| | - Li-Jung Kuo
- Marine Sciences Laboratory, Pacific Northwest National Laboratory, 1529 W. Sequim Bay Rd., Sequim, WA, 98382, USA
| | - Nicholas D Ward
- Marine Sciences Laboratory, Pacific Northwest National Laboratory, 1529 W. Sequim Bay Rd., Sequim, WA, 98382, USA.,School of Oceanography, University of Washington, Seattle, WA, 98105, USA
| | - Richard C Zimmerman
- Department of Ocean, Earth & Atmospheric Sciences, Old Dominion University, Norfolk, VA, 23429, USA
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Bhagwat AS, McFadden BA. Trapping of a reaction intermediate by tetranitromethane during catalysis by ribulose biphosphate carboxylase. FEBS Lett 2001. [DOI: 10.1016/0014-5793(82)80190-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Hernandez JM, Baker SH, Lorbach SC, Shively JM, Tabita FR. Deduced amino acid sequence, functional expression, and unique enzymatic properties of the form I and form II ribulose bisphosphate carboxylase/oxygenase from the chemoautotrophic bacterium Thiobacillus denitrificans. J Bacteriol 1996; 178:347-56. [PMID: 8550452 PMCID: PMC177664 DOI: 10.1128/jb.178.2.347-356.1996] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The cbbL cbbS and cbbM genes of Thiobacillus denitrificans, encoding form I and form II ribulose 1,5-bisphosphate carboxylase/oxygenase (RubisCO), respectively, were found to complement a RubisCO-negative mutant of Rhodobacter sphaeroides to autotrophic growth. Endogenous T. denitrificans promoters were shown to function in R. sphaeroides, resulting in high levels of cbbL cbbS and cbbM expression in the R. sphaeroides host. This expression system provided high levels of both T. denitrificans enzymes, each of which was highly purified. The deduced amino acid sequence of the form I enzyme indicated that the large subunit was closely homologous to previously sequenced form I RubisCO enzymes from sulfur-oxidizing bacteria. The form I T. denitrificans enzyme possessed a very low substrate specificity factor and did not exhibit fallover, and yet this enzyme showed a poor ability to recover from incubation with ribulose 1,5-bisphosphate. The deduced amino acid sequence of the form II T. denitrificans enzyme resembled those of other form II RubisCO enzymes. The substrate specificity factor was characteristically low, and the lack of fallover and the inhibition by ribulose 1,5-bisphosphate were similar to those of form II RubisCO obtained from nonsulfur purple bacteria. Both form I and form II RubisCO from T. denitrificans possessed high KCO2 values, suggesting that this organism might suffer in environments containing low levels of dissolved CO2. These studies present the initial description of the kinetic properties of form I and form II RubisCO from a chemoautotrophic bacterium that synthesizes both types of enzyme.
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Affiliation(s)
- J M Hernandez
- Ohio State Biochemistry Program, Ohio State University, Columbus 43210-1292, USA
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Ribulose-1,5-bisphosphate carboxylase/oxygenase from a nitrite-oxidizing chemoautotroph, Nitrobacter agilis ATCC 14123: Purification and properties. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/0922-338x(96)82219-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Haining RL, McFadden BA. Active-site histidines in recombinant cyanobacterial ribulose-1,5-bisphosphate carboxylase/oxygenase examined by site-directed mutagenesis. PHOTOSYNTHESIS RESEARCH 1994; 41:349-356. [PMID: 24310117 DOI: 10.1007/bf00019412] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/1994] [Accepted: 04/18/1994] [Indexed: 06/02/2023]
Abstract
The functions of His(291), His(295) and His(324) at the active-site of recombinant A. nidulans ribulose-1,5-bisphosphate carboxylase/ oxygenase have been explored by site-directed mutagenesis. Replacement of His(291) by K or R resulted in unassembled proteins, while its replacement by E, Q or N resulted in assembled but inactive proteins. These results are in accord with a metal ion-binding role of this residue in the activated ternary complex by analogy to x-ray crystallographic analyses of tobacco and spinach enzymes.His(324) (H327 in spinach), which is located within bonding distance of the 5-phosphate of bound bi-substrate analog 2-carboxyarabinitol 1,5-bisphosphate in the crystal structures, has been substituted by A, K, R, Q and N. Again with the exception of the H324K and R variants, these changes resulted in detectable assembled protein. The mutant H324A protein exhibited no detectable carboxylase activity, whereas the H324Q and H324N changes resulted in purifiable holoenzyme with 2.0 and 0.1% of the recombinant wild-type specific carboxylase activity, respectively. These results are consistent with a phosphate binding role for this residue.The replacement of His(295), which has been suggested to aid in phosphate binding, with Ala in the A. nidulans enzyme leads to a mutant with 5.8% of the recombinant wild-type carboxylase activity. All other mutations at this position resulted in unassembled proteins. Purified H295A and H324Q enzymes had elevated Km(RuBP) values and unchanged CO2/O2 specificity factors compared to recombinant wild-type.
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Affiliation(s)
- R L Haining
- Department of Biochemistry and Biophysics, Washington State University, 99164-4660, Pullman, WA, USA
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Stoner MT, Shively JM. Cloning and expression of the D-ribulose-1,5-bisphosphate carboxylase/oxygenase form II gene from Thiobacillus intermedius in Escherichia coli. FEMS Microbiol Lett 1993; 107:287-92. [PMID: 8472910 DOI: 10.1111/j.1574-6968.1993.tb06044.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Both form I and II ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) genes were detected in Thiobacillus intermedius by heterologous hybridization using specific probes from Anacystis nidulans and Rhodobacter sphaeroides, respectively. However, only the previously reported form I enzyme could be demonstrated in cells grown under a number of different conditions. The reason(s) why the form II gene is not expressed in T. intermedius is/are not clear at this time. The form II gene was isolated from a lambda library by screening with the Rb. sphaeroides probe. A SalI fragment from this clone was ligated into pUC8 and transformed into Escherichia coli DH5 alpha. Subclones pTi20IIA and pTi20IIB representing both orientations relative to the lac promoter were isolated. Low levels of RuBisCO activity were detected in both induced and non-induced pTi20IIA indicating the probable expression from a T. intermedius promoter. Induced pTi20IIB produced much higher levels of enzyme activity. Analysis of cell-free extracts using sucrose density gradients confirmed the expression of a form II RuBisCO similar in size to that found in Rhodobacter capsulatus. Other Calvin cycle genes were not clustered with either the form I or form II genes.
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Affiliation(s)
- M T Stoner
- Department of Biological Sciences, Clemson University, South Carolina 29634-1903
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English RS, Williams CA, Lorbach SC, Shively JM. Two forms of ribulose-1,5-bisphosphate carboxylase/oxygenase fromThiobacillus denitrificans. FEMS Microbiol Lett 1992. [DOI: 10.1111/j.1574-6968.1992.tb05299.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Lee BG, Read BA, Tabita FR. Catalytic properties of recombinant octameric, hexadecameric, and heterologous cyanobacterial/bacterial ribulose- 1,5-bisphosphate carboxylase/oxygenase. Arch Biochem Biophys 1991; 291:263-9. [PMID: 1952939 DOI: 10.1016/0003-9861(91)90133-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The recent isolation of a catalytically competent recombinant octameric core of the hexadecameric ribulose-1,5-bisphosphate carboxylase/oxygenase from the cyanobacterium Anacystis nidulans (Synechococcus) (B. Lee and F. R. Tabita, 1990, Biochemistry 29, 9352-9357) has provided a useful system for examining the properties of this enzyme in the absence of small subunits. Unlike most sources of hexadecameric ribulose bisphosphate carboxylase, the nonactivated Anacystis holoenzyme was not inhibited markedly by preincubation with ribulose 1,5-bisphosphate. This was also true for the Anacystis octameric core and a heterologous recombinant enzyme that comprised large subunits from Anacystis and small subunits from the bacterium Alcaligenes eutrophus, suggesting that substrate-mediated inactivation is not influenced by small subunits. In addition, the CO2/O2 specificity factor was not affected by the source of the small subunits incorporated into the structure of the hexadecameric protein, in agreement with previous in vitro heterologous reconstitution studies. The activated octameric Anacystis enzyme, however, was significantly more sensitive to inhibition by the phosphorylated effector 6-phosphogluconate than were the hexadecameric Alcaligenes and Anacystis enzymes and the heterologous Anacystis-Alcaligenes hybrid.
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Affiliation(s)
- B G Lee
- Department of Microbiology, Ohio State University, Columbus 43210
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Haining RL, McFadden BA. A critical arginine in the large subunit of ribulose bisphosphate carboxylase/oxygenase identified by site-directed mutagenesis. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)39379-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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Heda GD, Madigan MT. Purification and characterization of the thermostable ribulose-1,5-bisphosphate carboxylase/oxygenase from the thermophilic purple bacterium Chromatium tepidum. EUROPEAN JOURNAL OF BIOCHEMISTRY 1989; 184:313-9. [PMID: 2507319 DOI: 10.1111/j.1432-1033.1989.tb15021.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The Calvin cycle enzyme ribulose-bisphosphate carboxylase/oxygenase has been purified and characterized from the thermophilic and obligately anaerobic purple sulfur bacterium, Chromatium tepidum. The enzyme is an L8S8 carboxylase with a molecular mass near 550 kDa. No evidence for a second form of the enzyme lacking small subunits was obtained. C. tepidum ribulose-bisphosphate carboxylase/oxygenase was stable to heating to temperatures of 60 degrees C and could be readily purified in an active form at room temperature. Both carboxylase and oxygenase activities of this enzyme were Mg2+-dependent and carboxylase activity was sensitive to the effector 6-phosphogluconic acid. The Km for ribulose bisphosphate for the carboxylase activity of the C. tepidum enzyme was substantially higher than that observed in mesophilic Calvin cycle autotrophs. Amino acid composition and immunological analyses of C. tepidum and Chromatium vinosum ribulose-bisphosphate carboxylases showed the enzymes to be highly related despite significant differences in heat stability. It is hypothesized that thermal stability of C. tepidum ribulose-bisphosphate carboxylase/oxygenase is due to differences in primary structure affecting folding patterns in both the large and small subunits and is clearly not the result of any unique quaternary structure of the thermostable enzyme.
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Affiliation(s)
- G D Heda
- Department of Microbiology, Southern Illinois University, Carbondale 62901
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Affiliation(s)
- G A Codd
- Department of Biological Sciences, University of Dundee, UK
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Suzuki A. Ribulose 1,5-bisphosphate carboxylase-oxygenase. I. Structural, immunochemical and catalytic properties. Biochimie 1987; 69:723-34. [PMID: 3120806 DOI: 10.1016/0300-9084(87)90193-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Some structural, immunochemical and catalytic properties are examined for ribulose 1,5-bisphosphate carboxylase-oxygenase from various cellular organisms including bacteria, cyanobacteria, algae and higher plants. The native enzyme molecular masses and the subunit polypeptide compositions vary according to enzyme sources. The molecular masses of the large and small subunits from different cellular organisms, on the other hand, show a relatively high homology due to their well-conserved primary amino acid sequence, especially that of the large subunit. In higher plants, the native enzyme and the large subunit are recognized by the antibodies raised against either the native or large subunit, whereas the small subunit apparently cross-reacts only with the antibodies directed against itself. A wide diversity exists, however, in the serological response of the native enzyme and its subunits with antibodies directed against the native enzyme or its subunits from different cellular organisms. According to numerous kinetic studies, the carboxylase and oxygenase reactions of the enzyme with ribulose 1,5-bisphosphate and carbon dioxide or oxygen require activation by carbon dioxide and magnesium prior to catalysis with ribulose 1,5-bisphosphate and carbon dioxide or oxygen. The activation and catalysis are also under the regulation of other metal ions and a number of chloroplastic metabolites. Recent double-labeling experiments using radioactive ribulose 1,5-bisphosphate and 14CO2 have elucidated the carboxylase/oxygenase ratios of the enzymes from different organisms. Another approach, i.e., genetic experiments, has also been used to examine the modification of the carboxylase/oxygenase ratio.
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Affiliation(s)
- A Suzuki
- Laboratoire du Métabolisme et de la Nutrition des Plantes, INRA, Versailles, France
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Chory J, Donohue TJ, Varga AR, Staehelin LA, Kaplan S. Induction of the photosynthetic membranes of Rhodopseudomonas sphaeroides: biochemical and morphological studies. J Bacteriol 1984; 159:540-54. [PMID: 6611335 PMCID: PMC215678 DOI: 10.1128/jb.159.2.540-554.1984] [Citation(s) in RCA: 108] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Cells of Rhodopseudomonas sphaeroides grown in a 25% O2 atmosphere were rapidly subjected to total anaerobiosis in the presence of light to study the progression of events associated with the de novo synthesis of the inducible intracytoplasmic membrane (ICM). This abrupt change in physiological conditions resulted in the immediate cessation of cell growth and whole cell protein, DNA, and phospholipid accumulation. Detectable cell growth and whole cell protein accumulation resumed ca. 12 h later. Bulk phospholipid accumulation paralleled cell growth, but the synthesis of individual phospholipid species during the adaptation period suggested the existence of a specific regulatory site in phospholipid synthesis at the level of the phosphatidylethanolamine methyltransferase system. Freeze-fracture electron microscopy showed that aerobic cells contain small indentations within the cell membrane that appear to be converted into discrete ICM invaginations within 1 h after the imposition of anaerobiosis. Microscopic examination also revealed a series of morphological changes in ICM structure and organization during the lag period before the initiation of photosynthetic growth. Bacteriochlorophyll synthesis and the formation of the two light-harvesting bacteriochlorophyll-protein complexes of R. sphaeroides (B800-850 and B875) occurred coordinately within 2 h after the shift to anaerobic conditions. Using antibodies prepared against various ICM-specific polypeptides, the synthesis of reaction center proteins and the polypeptides associated with the B800-850 complex was monitored. The reaction center H polypeptide was immunochemically detected at low levels in the cell membrane of aerobic cells, which contained no detectable ICM or bacteriochlorophyll. The results are discussed in terms of the oxygen-dependent regulation of gene expression in R. sphaeroides and the possible role of the reaction center H polypeptide and the cell membrane indentations in the site-specific assembly of ICM pigment-protein complexes during the de novo synthesis of the ICM.
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Roach DJ, McFadden BA. The response to ribulose bisphosphate(4-) (RuBP (4-)) and RuBP-Mg (2-) in catalysis by structurally divergent RuBP carboxylase/oxygenases. PHOTOSYNTHESIS RESEARCH 1983; 4:111-117. [PMID: 24458447 DOI: 10.1007/bf00052372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/1982] [Revised: 11/24/1982] [Indexed: 06/03/2023]
Abstract
Free ribulose bisphosphate (RuBP(4-)) rather than its magnesium complex (RuBP-Mg(2-)) was the apparent substrate for spinach ribulose bisphosphate carboxylase/oxygenase. The apparent Km for total RuBP (pH 8.0 at 30° C) increased with increasing Mg(2+) concentrations from 11.6 μM at 13.33 mM Mg(2+) to 32.6 μM at 40.33 mM Mg(2+). Similarly the apparent Km for RuBP-Mg(2-) complex increased with increasing Mg(2+) from 9.4 μM at 13.33 mM Mg(2+) to 29.7 μM at 40.33 mM Mg(2+). However, the Km values for uncomplexed RuBP(4-) were independent of the (saturating) concentration of Mg(2+) (Km=2.2 μM). The Vmax did not vary with the changing concentrations of Mg(2+).In contrast, the Km for total RuBP remained constant with varying Mg(2+) concentrations (Km=59.5 μM) for the enzyme from R. rubrum. The apparent Km for the RuBP-Mg(2-) complex decreased with increasing Mg(2+) concentrations from 16.0 μM at 7.5 mM Mg(2+) to 5.9 μM at 27.5 mM Mg(2+). The initial velocity for the C. vinosum enzyme was also found to be independent of the (saturating) concentration of Mg(2+) when total RuBP was varied in the assay. Thus the response to total RuBP by these two bacterial enzymes, which markedly differ in structure, was closely similar.
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Affiliation(s)
- D J Roach
- Biochemistry/Biophysics Program, Washington State University, 99164, Pullman, WA
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Roach DJ, Gollnick PD, McFadden BA. Interaction of ribulose bisphosphate carboxylase/oxygenase with 2-carboxyhexitol 1,6-bisphosphates. Arch Biochem Biophys 1983; 222:87-94. [PMID: 6573158 DOI: 10.1016/0003-9861(83)90505-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
2-C-Carboxy-D-glucitol 1,6-bisphosphate (CGBP) and 2-C-carboxy-D-mannitol 1,6-bisphosphate (CMBP) have been synthesized, isolated, and the structures of these compounds and the derived lactones elucidated by NMR spectroscopy and periodate oxidation. Both carboxyhexitol bisphosphates, which are homologs of the transition state analog 2-C-carboxy-D-arabinitol 1,5-bisphosphate, exhibit competitive inhibiton of ribulose bisphosphate carboxylase/oxygenase (EC 4.1.1.9) isolated from spinach (Spinacia oleracea), with respect to ribulose 1,5-bisphosphate. CMBP was a more potent inhibitor (100-fold) displaying an inhibition constant (Ki at pH 8.0 and 30 degrees C) of 1-2 microM with enzymes from spinach, barley (Hordeum vulgare), and Chromatium vinosum. In contrast the Rhodospirillum rubrum enzyme was inhibited about 40-fold more weakly (Ki = 53 microM at pH 8.0 and 30 degrees C). Both CGBP and CMBP potentiated activation of RuBP carboxylase from spinach and R. rubrum.
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Roach DJ, McFadden BA. The response to ribulose bisphosphate(4-) (RuBP (4-)) and RuBP-Mg (2-) in catalysis by structurally divergent RuBP carboxylase/oxygenases. PHOTOSYNTHESIS RESEARCH 1983; 4:111-117. [PMID: 24458390 DOI: 10.1007/bf00041806] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/1982] [Revised: 11/24/1992] [Indexed: 06/03/2023]
Abstract
Free ribulose hisphosphate (RuBP(4-)) rather than its magnesium complex (RuBP-Mg(2-)) was the apparent substrate for spinach ribulose bisphosphate carboxylase/oxygenase. The apparent Km for total RuBP (pH 8.0 at 30° C) increased with increasing Mg(2+) concentrations from 11.6 μM at 13.33 mM Mg(2+) to 32.6 μM at 40.33 mM Mg(2+). Similarly the apparent Km for RuBP-Mg(2-) complex increased with increasing Mg(2+) from 9.4 μM at 13.33 mM Mg(2+) to 29.7 μM at 40.33 mM Mg(2+). However, the Km values for uncomplexed RuBP(4-) were independent of the (saturating) concentration of Mg(2+) (Km=2.2 μM). The Vmax did not vary with the changing concentrations of Mg(2+).In contrast, the Km for total RuBP remained constant with varying Mg(2+) concentrations (Km=59.5 μM) for the enzyme from R. rubrum. The apparent Km for the RuBP-Mg(2-) complex decreased with increasing Mg(2+) concentrations from 16.0 μM at 7.5 mM Mg(2+) to 5.9 μM at 27.5 mM Mg(2+). The initial velocity for the C. vinosum enzyme was also found to be independent of the (saturating) concentration of Mg(2+) when total RuBP was varied in the assay. Thus the response to total RuBP by these two bacterial enzymes, which markedly differ in structure, was closely similar.
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Affiliation(s)
- D J Roach
- Biochemistry/Biophysics Program, Washington State University, 99164, Pullman, WA
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Schloss JV, Phares EF, Long MV, Norton IL, Stringer CD, Hartman FC. Ribulosebisphosphate carboxylase/oxygenase from Rhodospirillum rubrum. Methods Enzymol 1982; 90 Pt E:522-8. [PMID: 6818424 DOI: 10.1016/s0076-6879(82)90179-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Hatch AL, Jensen RG. Regulation of ribulose-1,5-bisphosphate carboxylase from tobacco: changes in pH response and affinity for CO2 and Mg2+ induced by chloroplast intermediates. Arch Biochem Biophys 1980; 205:587-94. [PMID: 6781414 DOI: 10.1016/0003-9861(80)90142-3] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Doolittle WF. The cyanobacterial genome, its expression, and the control of that expression. Adv Microb Physiol 1980; 20:1-102. [PMID: 119432 DOI: 10.1016/s0065-2911(08)60206-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Tabita FR, Colletti C. Carbon dioxide assimilation in cyanobacteria: regulation of ribulose, 1,5-bisphosphate carboxylase. J Bacteriol 1979; 140:452-8. [PMID: 40958 PMCID: PMC216669 DOI: 10.1128/jb.140.2.452-458.1979] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Cyanobacteria assimilate carbon dioxide through the Calvin cycle and therefore must regulate the activity of ribulose 1,5-bisophosphate carboxylase. Using an in situ assay, as well as measuring the activity in crude, partially purified, and homogeneous preparations, we can show that a number of phosphorylated intermediates exert a regulatory role. Three diverse organisms, Agmenellum quadruplicatum, Aphanocapsa 6714, and Anabaena sp. CA, were studied, and it was found that the in situ and cell-free carboxylase activities were particularly affected by low levels of phosphogluconate and reduced nicotinamide adenine dinucleotide phosphate. There was a marked activation by these ligands when the inactive enzyme was assayed in the presence of low levels of bicarbonate, a result significantly different from a previous report. Moreover, the fully activated enzyme was inhibited by phosphogluconate. In situ Anabaena CA carboxylase activity exhibited a particular capacity for activation by phosphogluconate and reduced nicotinamide adenine dinucleotide phosphate. However, activation of the crude, partially purified, or homogeneous Anabaena CA carboxylase by phosphogluconate and reduced nicotinamide adenine dinucleotide phosphate was significantly decreased when compared with enzyme activity in permeabilized cells. It appears that the microenvironment or the conformation of the enzyme within the cell may be significantly different from that of the isolated enzyme.
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Harrison D, Rogers L, Smith A. d-Ribulose 1,5-bisphosphate carboxylase of the nitrifying bacterium, Nitrobacter agilis. FEMS Microbiol Lett 1979. [DOI: 10.1111/j.1574-6968.1979.tb04275.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Purohit K, McFadden BA. Ribulose 1,5-bisphosphate carboxylase and oxygenase from Thiocapsa roseopersicina: activation and catalysis. Arch Biochem Biophys 1979; 194:101-6. [PMID: 109042 DOI: 10.1016/0003-9861(79)90599-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Schloss JV, Phares EF, Long MV, Norton IL, Stringer CD, Hartman FC. Isolation, characterization, and crystallization of ribulosebisphosphate carboxylase from autotrophically grown Rhodospirillum rubrum. J Bacteriol 1979; 137:490-501. [PMID: 33152 PMCID: PMC218475 DOI: 10.1128/jb.137.1.490-501.1979] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Serial culture of Rhodospirillum rubrum with 2% CO2 in H2 as the exclusive carbon source resulted in a rather large fraction of the soluble protein (greater than 40%) being comprised of ribulosebisphosphate carboxylase (about sixfold higher than the highest value previously reported). Isolation of the enzyme from these cells revealed that it has physical and kinetic properties similar to those previously described for the enzyme derived from cells grown on butyrate. Notably, the small subunit (which is a constituent of the carboxylase from eucaryotes and most procaryotes) was absent in the enzyme from autotrophically grown R. rubrum. Edman degradation of the purified enzyme revealed that the NH2 terminus is free (in contrast to the catalytic subunit of the carboxylase from eucaryotes) and that the NH2-terminal sequence is Met-Asp-Gln-Ser-Ser-Arg-Tyr-Val-Asn-Leu-Ala-Leu-Lys-Glu-Glu-Asp-Leu-Ile-Ala-Gly-Gly-Glx-His-Val-Leu-. Crystals of the enzyme were readily obtained by dialysis against distilled water.
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Lawlis VB, Gordon GL, McFadden BA. Regulation of activation of ribulose bisphosphate carboxylase from Pseudomonas oxalaticus. Biochem Biophys Res Commun 1978; 84:699-705. [PMID: 718711 DOI: 10.1016/0006-291x(78)90761-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Shively JM, Saluja A, McFadden BA. Ribulose bisphosphate carboxylase from methanol-grown Paracoccus denitrificans. J Bacteriol 1978; 134:1123-32. [PMID: 659365 PMCID: PMC222363 DOI: 10.1128/jb.134.3.1123-1132.1978] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Paracoccus denitrificans grows on methanol as the sole source of energy and carbon, which it assimilates aerobically via the reductive pentose phosphate cycle. This gram-negative bacterium grew rapidly on 50 mM methanol (generation time, 7 h, 30 degrees C) in excellent yield (3 g of wet-packed cells per liter of culture). Electron microscopic studies indicated that the late-log-phase cells were coccoid, having a thick envelope surrounding a layer of more diffuse electron-dense material and a relatively electron-transparent core. Ribulose bisphosphate carboxylase in the 15,000 X g supernatant of fresh cells had specific activities (micromoles of CO2 fixed per minute per milligram of protein) of 0.026, 0.049, 0.085, 0.128, and 0.034 during the lag, early, mild-, and late log, and late stationary phases, respectively. The enzyme was purified 40-fold by pelleting at 159,000 X g, salting out, sedimentation into a 0.2 to 0.8 M linear sucrose gradient, and elution from a diethylaminoethyl-Sephadex column. The enzyme was homogeneous by the criteria of electrophoresis on polyacrylamide gels polymerized from several acrylamide concentrations and sedimentation behavior. The molecular weight of the native enzyme, as measured by gel electrophoresis and gel filtration, averaged 525,000. Sodium dodecyl sulfate dissociated the enzyme into two types of subunits with molecular weights of 55,000 and 13,600. The S20,w of the enzyme was 14.0 Km values for ribulose bisphosphate and CO2 were 0.166 and 0.051 mM, respectively, and the enzyme was inhibited to the extent of 94% by 1 mM 6-phosphogluconate.
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Whitman WB, Tabita FR. Modification of Rhodospirillum rubrum ribulose bisphosphate carboxylase with pyridoxal phosphate. 2. Stoichiometry and kinetics of inactivation. Biochemistry 1978; 17:1288-93. [PMID: 418800 DOI: 10.1021/bi00600a024] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Rhodospirillum rubrum ribulose bisphosphate carboxylase contains two high affinity binding sites for pyridoxal phosphate and two catalytic sites per dimer. However, pyridoxal phosphate binding at only one site is sufficient for inactivation of both catalytic sites. In the presence of 20 mM bicarbonate, 10 mM magnesium, and pyridoxal phosphate, the rates of inactivation and Schiff base formation are pseudo-first-order and show saturation kinetics. These observations provide additional evidence that pyridoxal phosphate binds at the active site of the R. rubrum carboxylase. It is also proposed that the large subunit may contain regulatory as well as catalytic properties.
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Whitman WB, Tabita FR. Modification of Rhodospirillum rubrum ribulose bisphosphate carboxylase with pyridoxal phosphate. 1. Identification of a lysyl residue at the active site. Biochemistry 1978; 17:1282-7. [PMID: 26381 DOI: 10.1021/bi00600a023] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Ribulose 1,5-bisphosphate carboxylase isolated from Rhodospirillum rubrum was strongly inhibited by low concentrations of pyridoxal 5'-phosphate. Activity was protected by the substrate ribulose bisphosphate and to a lesser extent by other phosphorylated compounds. Pyridoxal phosphate inhibition was enhanced in the presence of magnesium and bicarbonate, but not in the presence of either compound alone. Concomitant with inhibition of enzyme activity, pyridoxal phosphate forms a Schiff base with the enzyme which is reversible upon dialysis and reducible with sodium borohydride. Subsequent to reduction of the Schiff base with tritiated sodium borohydride, tritiated N6-pyridoxyllysine could be identified in the acid hydrolysate of the enzyme. Only small amounts of this compound were present when the reduction was performed in the presence of carboxyribitol bisphosphate, an analogue of the intermediate formed during the carboxylation reaction. Therefore, it is concluded that pyridoxal phosphate modifies a lysyl residue close to or at the active site of ribulose bisphosphate carboxylase.
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McFadden BA, Purohit K. Chemosynthetic, photosynthetic, and cyanobacterial ribulose bisphosphate carboxylase. BASIC LIFE SCIENCES 1978; 11:179-207. [PMID: 106835 DOI: 10.1007/978-1-4684-8106-8_13] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Gibson JL, Tabita FR. Isolation and preliminary characterization of two forms of ribulose 1,5-bisphosphate carboxylase from Rhodopseudomonas capsulata. J Bacteriol 1977; 132:818-23. [PMID: 21872 PMCID: PMC235583 DOI: 10.1128/jb.132.3.818-823.1977] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The presence of two distinct forms of ribulose 1,5-bisphosphate carboxylase has been demonstrated in extracts of Rhodopseudomonas capsulata, similar to the form I (peak I) and form II (peak II) carboxylases previously described from R. sphaeroides (J. Gibson and F. R. Tabita, J. Biol. Chem 252:943-949, 1977). The two activities, separated by diethylaminoethyl-cellulose chromatography, were shown to be of different molecular size after assay on polyacrylamide gels. The higher-molecular-weight carboxylase from R. capsulata was designated form I-C, whereas the smaller enzyme was designated form II-C. Catalytic studies revealed significant differences between the two enzymes in response to pH and the effector 6-phosphogluconate. Immunological studies with antisera directed against the carboxylases from R. sphaeroides demonstrated antigenic differences between the two R. capsulata enzymes; cross-reactivity was observed only between R. sphaeroides anti-form II serum and the corresponding R. capsulata enzyme, form II-C.
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Characterization of antiserum directed against form II ribulose 1,5-bisphosphate carboxylase from Rhodopseudomonas sphaeroides. J Bacteriol 1977; 131:1020-2. [PMID: 70425 PMCID: PMC235564 DOI: 10.1128/jb.131.3.1020-1022.1977] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Antiserum directed against form II ribulose 1,5-bisphosphate carboxylase from Rhodopseudomonas sphaeroides showed no cross-reactivity towards the form I enzyme as evidenced by a lack of immunopreciptation. In addition, this antiserum failed to inhibit form I enzymatic activity.
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Schloss JV, Hartman FC. Reaction of ribulosebisphosphate carboxylase from rhodospirlilum rubrum with the potential affinity label 3-bromo-1,4-dihydroxy-2-butanone 1,4-biphosphate. Biochem Biophys Res Commun 1977; 75:320-8. [PMID: 403917 DOI: 10.1016/0006-291x(77)91045-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Gibson JL, Tabita FR. Different molecular forms of D-ribulose-1,5-bisphosphate carboxylase from Rhodopseudomonas sphaeroides. J Biol Chem 1977. [DOI: 10.1016/s0021-9258(19)75189-8] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Whitman W, Tabita FR. Inhibition of D-ribulose 1,5-bisphosphate carboxylase by pyridoxal 5'-phosphate. Biochem Biophys Res Commun 1976; 71:1034-9. [PMID: 823940 DOI: 10.1016/0006-291x(76)90758-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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40
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Badger MR, Lorimer GH. Activation of ribulose-1, 5-bisphosphate oxygenase, The role of Mg2+, CO2, and pH. Arch Biochem Biophys 1976; 175:723-9. [PMID: 8715 DOI: 10.1016/0003-9861(76)90565-8] [Citation(s) in RCA: 76] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Purohit K, McFadden BA, Cohen AL. Purification, quaternary structure, composition, and properties of D-ribulose-1,5-bisphosphate carboxylase from Thiobacillus intermedius. J Bacteriol 1976; 127:505-15. [PMID: 819423 PMCID: PMC233084 DOI: 10.1128/jb.127.1.505-515.1976] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
D-Ribulose-1,5-bisphosphate (RuBP) carboxylase has been purified from glutamate-CO2-S2O3(2)-grown Thiobacillus intermedius by pelleting the enzyme from the high-speed supernatant and by intermediary crystallization followed by sedimentation into a discontinuous 0.2 to 0.8 M sucrose gradient. The enzyme was homogeneous by the criteria of electrophoresis on polyacrylamide gels of several acrylamide concentrations, sedimentation velocity and equilibrium measurements, and electron microscopic observations of negatively stained preparations. The molecular weights of the enzyme determined by sedimentation equilibrium and light-scattering measurements averaged 462,500 +/- 13,000. The enzyme consisted of closely similar or identical polypeptide chains of a molecular weight of 54,500 +/- 5,450 determined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The S(0)20,w of the enzyme was 18.07S +/- 0.22. Electron microscopic examination suggested that the octomeric enzyme (inferred from the molecular measurements mentioned) had a cubical structure. The specific activity of the enzyme was 2.76 mumol of RuBP-dependent CO2 fixed/min per mg of protein (at pH 8 and 30 C), and the turnover number in terms of moles of CO2 fixed per mole of catalytic site per second was 2.6. The enzyme was stable for 3 months at -20 C and at least 4 weeks at 0 C. The apparent Km for CO2 was 0.75 mM, and Km values for RuBP and Mg2+ were 0.076 and 3.6 mM, respectively. Dialyzed enzyme could be fully reactivated by the addition of 20 mM Mg2+ and partially reactivated by 20 mM Co2+, but Cd2+, Mn2+, Ca2+, and Zn2+ had no effect. The compound 6-phosphogluconate was a linear competitive inhibitor with respect to RuBP when it had been preincubated with enzyme, Mg2+, and HCO3-.
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Charles AM, White B. Physical properties and metabolite regulation of ribulose bisphosphate carboxylase from Thiobacillus A2. Arch Microbiol 1976; 108:203-9. [PMID: 1275653 DOI: 10.1007/bf00428952] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Purified ribulose-bisphosphate carboxylase (EC 4.1.1.39) was strongly and equally inhibited either by ADP or GDP and to a lesser extent by IDP. AMP or ATP exerted little effect on activity. Inhibition by the nucleotide diphosphates was competitive with respect to RuBP and non-competitive with respect to "CO2" and Mg2+, respectively. Treatment of the enzyme with urea or guanidine-HCl resulted in rapid loss of activity that was not restored by dialysis even in the presence of Mg2+ and cysteine. Sodium dodecyl sulfate electrophoresis of 8.0 M urea treated enzyme revealed the presence of a fast-moving (small) sub-unit with molecular weight 14150 and a slower moving (large) sub-unit with molecular weight 68000. Examination of native enzyme by sodium dodecyl sulfate electrophoresis gave sub-units of 13700 and 55500 respectively. The amino acid content standardized to phenylalanine was essentially similar to that from other sources. Arrhenius plots showed a "break" at 29 degrees C with an Ea of 12.34 kcal per mole for the steeper part of the curve and a deltaH of 11.43 kcal per mole while for the less steep region, the Ea was 1.04 kcal per mole and the deltaH 1.92 kcal per mole.
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Walker DA. Regulatory mechanisms in photosynthetic carbon metabolism. CURRENT TOPICS IN CELLULAR REGULATION 1976; 11:203-41. [PMID: 11968 DOI: 10.1016/b978-0-12-152811-9.50013-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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McCarthy JT, Charles AM. Properties and regulation of ribulose diphosphate carboxylase from Thiobacillus novellus. Arch Microbiol 1975; 105:51-9. [PMID: 242294 DOI: 10.1007/bf00447113] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Ribulose-diphosphate carboxylase from Thiobacillus novellus has been purified to hemogeneity as observed by polyacrylamide gel electrophoresis and U.V. light observation during sedimentation velocity analysis. The optimum pH for the enzyme with Tris-HCl buffers was about 8.2. Concentrations of this buffer in excess of 80 mM were inhibitory. The apparent Km for RuDP was about 14.8 muM with a Hill value of 1.5, for HCO3- the apparent Km was about 11.7 mM with an n value of 1.18 and for Mg2+ about 0.61 mM. The enzyme was specific for this cation. Relatively high concentrations of either Hg2+ or pCMB were required before significant inhibition was observed. Activity declined slowly during a 4-hr incubation period in either 3.0 M or 8.0 M urea. Incubation for 12 hrs resulted in complete loss of activity which was not prevented by 10 mM Mg2+ and was not reversed by dialysis and subsequent addition of 10 mM cysteine. Polyacrylamide gel electrophoresis revealed a loss of the major band and the appearance of 2 new bands. SDS polyacrylamide gel electrophoresis gave an average M.W. of 73500 +/- 2500 for the slower moving band and 12250 +/- 2500 for the faster moving. However, incubation in urea for up to 40 hrs revealed a decrease in the M.W. of the slower moving band to about 60000. The Ea for the enzyme was calculated to be about 18.85 kcal mole-1, with the possibility of a "break" between 40 and 50 degrees C. The Q10 was 3.07 between 20 and 30 degrees C whereas between 30 to 40 degrees C it was 3.31. Only phosphorylated compounds caused significant inhibition of enzyme activity. They included ADP, FDP, F6P, G6P, PEP, 6PG, 2-PGA, R1P, R5P, and Ru5p.
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McFadden BA, Lord JM, Rowe A, Dilks S. Composition, quaternary structure, and catalytic properties of D-ribulose-1, 5-bisphosphate carboxylase from Euglena gracilis. EUROPEAN JOURNAL OF BIOCHEMISTRY 1975; 54:195-206. [PMID: 807477 DOI: 10.1111/j.1432-1033.1975.tb04129.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
D-Ribulose-1,5-bisphosphate carboxylase has been purified in one step by sedimenting extracts of autotrophically-grown Euglena gracilis into a linear 0.2-0.8 M sucrose density gradient. The resultant product was pure by the criteria of disc electrophoresis in gels polymerized from 5 or 7.5% acrylamide and sedimentation. The molecular weight of the enzyme estimated by density gradient centrifugation and electrophoresis in gels polymerized from various concentrations of acrylamide was 5.25 X 10(5). The S20,W was 16.4 S. Dissociation and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate established that the enzyme was composed of two types of subunits (mr 50,000 and 15,000). The oligomeric structure was visualized through negative staining and transmission electron microscopy leading to a model for the quaternary structure. Although the enzyme was moderately unstable, the estimated maximal specific activity was 1.6 mumol CO2 fixed min-1 mg protien-1 at 30 degrees C and pH 8.0 Km values were 2.2 m M, 15. 1 MUM and 0.63 mM for Mg2+, ribulose 1,5-bisphosphate, and CO2, respectively, when measured under air. 6-Phospho-D-gluconate was a noncompetitive inhibitor with respect to ribulose 1,5-bisphosphate (Ki = 0.04 mM). Oxygen was a competitive inhibitor with respect to CO2 suggesting that the enzyme was also an oxygenase. The latter was confirmed by experiments showing a molar equivalence between ribulose-1,5-bisphosphate-dependent oxygen consumption and phosphoglycerate production.
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McFadden BA, Tabita FR, Kuehn GD. Ribulose-diphosphate carboxylase from the hydrogen bacteria and Rhodospirillum rubrum. Methods Enzymol 1975; 42:461-72. [PMID: 805894 DOI: 10.1016/0076-6879(75)42152-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Duggan JX, Anderson LE. Light-regulation of enzyme activity in anacystis nidulans (Richt.). PLANTA 1975; 122:293-297. [PMID: 24435997 DOI: 10.1007/bf00385278] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/1974] [Accepted: 11/21/1974] [Indexed: 06/03/2023]
Abstract
The effect of light on the levels of activity of six enzymes which are light-modulated in higher plants was examined in the photosynthetic procaryot Anacystis nidulans. Ribulose-5-phosphate kinase (EC 2.7.1.19) was found to be light-activated in vivo and dithiothreitol-activated in vitro while glucose-6-phosphate dehydrogenase (EC 1.1.1.49) was light-inactivated and dithiothreitol-inactivated. The enzymes fructose-1,6-diphosphate phosphatase (EC 3.1.3.11), sedoheptulose-1,7-diphosphate phosphatase, NAD- and NADP-linked glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.12; EC 1.2.1.13) were not affected by light treatment of the intact algae, but sedoheptulose-diphosphate phosphatase and the glyceraldehyde-3-phosphate dehydrogenases were dithiothreitol-activated in crude extracts. Light apparently controls the activity of the reductive and oxidative pentose phosphate pathway in this photosynthetic procaryot as in higher plants, through a process which probably involves reductive modulation of enzyme activity.
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Affiliation(s)
- J X Duggan
- Department of Biological Sciences, University of Illinois at Chicago Circle, Box 4348, 60690, Chicago, Illinois, USA
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