Kinetics of Interactions between LOV Domains from Chlamydomonas Reinhardtii

Flagellar amputation in Chlamydomonas reinhardtii induces the accumulation of a specific set of RNAs, many of which encode flagellar proteins. We prepared a cDNA clone bank from RNA isolated from cells undergoing flagellar regeneration. From this bank, we selected clones that contain RNA sequences that display several different patterns of abundance regulation. Based on quantitation of the relative amounts of labeled, cloned cDNAs hybridizing to dots of RNA on nitrocellulose filters, the cloned sequences were divided into five regulatory classes: class I RNAs remain at constant abundance during flagellar regeneration; classes II, III, and IV begin to increase in abundance within a few minutes after deflagellation, reach maximal abundance at successively later times during regeneration, and return to control cell levels within 2 to 3 h; and class V RNA abundance decreases during flagellar regeneration. Alpha- and beta-tubulin mRNAs are included in regulatory class IV. The abundance kinetics of alpha-tubulin mRNAs differ slightly from those of beta-tubulin mRNAs. The availability of these clones makes possible studies on the mechanisms controlling the abundance of a wide variety of different RNA species during flagellar regeneration in Chlamydomonas.

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Experimental research on the photobiological hydrogen production kinetics of Chlamydomonas reinhardtii GY-D55

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2016.03.151 ◽

2016 ◽

Vol 41 (35) ◽

pp. 15651-15660 ◽

Cited By ~ 8

Author(s):

Zhen-Zong He ◽

Hong Qi ◽

Ming-Jian He ◽

Li-Ming Ruan

Keyword(s):

Hydrogen Production ◽

Chlamydomonas Reinhardtii ◽

Experimental Research ◽

Production Kinetics ◽

Kinetics Of

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Thylakoid membrane biogenesis in Chlamydomonas reinhardtii 137+. II. Cell-cycle variations in the synthesis and assembly of pigment.

The Journal of Cell Biology ◽

10.1083/jcb.93.2.411 ◽

1982 ◽

Vol 93 (2) ◽

pp. 411-416 ◽

Cited By ~ 9

Author(s):

D R Janero ◽

R Barrnett

Keyword(s):

Cell Cycle ◽

Chlamydomonas Reinhardtii ◽

Thylakoid Membrane ◽

Direct Analysis ◽

Cellular Level ◽

Periodic Pattern ◽

Cell Cycle Time ◽

Pigment Synthesis ◽

Thylakoid Biogenesis ◽

Kinetics Of

Synthesis of the chlorophyll and the major carotenoid pigments and their assembly into thylakoid membrane have been studied throughout the 12-h light/12-h dark vegetative cell cycle of synchronous Chlamydomonas reinhardtii 137+ (wild-type). Pulse exposure of cells to radioactive acetate under conditions in which labeling accurately reflects lipogenesis, followed by cellular fractionation to purify thylakoid membrane, allowed direct analysis of the pigment synthesis and assembly attendant to thylakoid biogenesis. All pigments are synthesized and assembled into thylakoids continuously, but differentially, with respect to cell-cycle time. Highest synthesis and assembly rates are confined to the photoperiod (mid-to-late G1) and support chlorophyll and carotenoid accretion before M-phase. The lower levels at which these processes take place during the dark period (S, M, and early-to-mid G1) have been ascribed to pigment turnover. Within this general periodic pattern, pigment synthesis and assembly occur in a "multi-step" manner, i.e., by a temporally-ordered, stepwise integration of the various pigments into the thylakoid membrane matrix. The cell-cycle kinetics of pigment assembly at the subcellular level mirror the kinetics of pigment synthesis at the cellular level, indicating that pigment synthesis not only provides chlorophyll and carotenoid for thylakoid biogenesis but may also serve as a critical rate-determinant to pigment assembly.

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Memory and Imprinting Effects in Multienzyme Complexes. II. Kinetics of the Bienzyme Complex from Chlamydomonas Reinhardtii and Hysteretic Activation of Chloroplast Oxidized Phosphoribulokinase

European Journal of Biochemistry ◽

10.1111/j.1432-1033.1997.t01-2-00085.x ◽

1997 ◽

Vol 246 (1) ◽

pp. 85-91 ◽

Cited By ~ 34

Author(s):

Sandrine Lebreton ◽

Brigitte Gontero ◽

Luisana Avilan ◽

Jacques Ricard

Keyword(s):

Chlamydomonas Reinhardtii ◽

Multienzyme Complexes ◽

Kinetics Of

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Kinematics and Kinetics of Flagellar Locomotion in Chlamydomonas Reinhardtii

ASME 2011 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2011-53290 ◽

2011 ◽

Author(s):

P. V. Bayly ◽

B. L. Lewis ◽

E. C. Ranz ◽

R. J. Okamoto ◽

R. B. Pless ◽

...

Keyword(s):

Chlamydomonas Reinhardtii ◽

Video Data ◽

Wild Type ◽

Viscous Forces ◽

Sorting Algorithms ◽

Theoretical Predictions ◽

Dynein Arms ◽

Kinetics Of ◽

Kinematics And Kinetics ◽

Surrounding Fluid

The forces exerted on the flagellum of the swimming alga Chlamydomonas reinhardtii by surrounding fluid are estimated from video data. “Wild-type” cells, as well as cells lacking inner dynein arms (ida3) and cells lacking outer dynein arms (oda2) were imaged (350 fps; 125 nm). Digital image registration and sorting algorithms provide high-resolution descriptions of the kinematics of the cell body and flagellum. The swimming cell is then modeled as an ellipsoid in Stokes flow, propelled by viscous forces that depend linearly on the velocity of the flagellum. The coefficients (CN and CT) that related normal and tangent forces on the flagellum to corresponding velocity components are estimated from equilibrium requirements. Their values are consistent among all three genotypes and similar to theoretical predictions.

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Deciphering the anti-Parkinson’s activity of sulphated polysaccharides from Chlamydomonas reinhardtii on the α-Synuclein mutants A30P, A53T, E46K, E57K and E35K

The Journal of Biochemistry ◽

10.1093/jb/mvz064 ◽

2019 ◽

Vol 166 (6) ◽

pp. 463-474 ◽

Cited By ~ 3

Author(s):

Gitanjali P Panigrahi ◽

Ankita R Rane ◽

Sirisha L Vavilala ◽

Sinjan Choudhary

Keyword(s):

Chlamydomonas Reinhardtii ◽

Morphological Changes ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

Aggregation Process ◽

Sulphated Polysaccharides ◽

Therapeutic Implications ◽

Transmission Electron ◽

Pharmaceutical Properties ◽

Kinetics Of

Abstract Parkinsonism-linked mutations in alanine and glutamic acid residues of the pre-synaptic protein α-Synuclein (α-Syn) affect specific tertiary interactions essential for stability of the native state and make it prone to more aggregation. Many of the currently available drugs used for the treatment of Parkinson’s disease (PD) are not very effective and are associated with multiple side effects. Recently, marine algae have been reported to have sulphated polysaccharides which offers multiple pharmaceutical properties. With this background, we have isolated sulphated polysaccharides from Chlamydomonas reinhardtii (Cr-SPs) and investigated their effects on inhibition of fibrillation/aggregation of α-Syn mutants through a combination of spectroscopic and microscopic techniques. The kinetics of α-Syn fibrillation establishes that Cr-SPs are very effective in inhibiting fibrillation of α-Syn mutants. The morphological changes associated with the fibrillation/aggregation process have been monitored by transmission electron microscopy. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis gel image suggests that Cr-SPs increase the amount of soluble protein after completion of the fibrillation/aggregation process. The circular dichroism results showed that Cr-SPs efficiently delay the conversion of native protein into β-sheet-rich structures. Thus, the current work has considerable therapeutic implications towards deciphering the potential of Cr-SPs to act against PD and other protein aggregation-related disorders.

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mRNA abundance changes during flagellar regeneration in Chlamydomonas reinhardtii.

Molecular and Cellular Biology ◽

10.1128/mcb.4.3.424 ◽

1984 ◽

Vol 4 (3) ◽

pp. 424-434 ◽

Cited By ~ 72

Author(s):

J A Schloss ◽

C D Silflow ◽

J L Rosenbaum

Keyword(s):

Chlamydomonas Reinhardtii ◽

Control Cell ◽

Beta Tubulin ◽

Rna Sequences ◽

Class V ◽

Alpha Tubulin ◽

Flagellar Regeneration ◽

Flagellar Proteins ◽

Kinetics Of ◽

Class Iv

Flagellar amputation in Chlamydomonas reinhardtii induces the accumulation of a specific set of RNAs, many of which encode flagellar proteins. We prepared a cDNA clone bank from RNA isolated from cells undergoing flagellar regeneration. From this bank, we selected clones that contain RNA sequences that display several different patterns of abundance regulation. Based on quantitation of the relative amounts of labeled, cloned cDNAs hybridizing to dots of RNA on nitrocellulose filters, the cloned sequences were divided into five regulatory classes: class I RNAs remain at constant abundance during flagellar regeneration; classes II, III, and IV begin to increase in abundance within a few minutes after deflagellation, reach maximal abundance at successively later times during regeneration, and return to control cell levels within 2 to 3 h; and class V RNA abundance decreases during flagellar regeneration. Alpha- and beta-tubulin mRNAs are included in regulatory class IV. The abundance kinetics of alpha-tubulin mRNAs differ slightly from those of beta-tubulin mRNAs. The availability of these clones makes possible studies on the mechanisms controlling the abundance of a wide variety of different RNA species during flagellar regeneration in Chlamydomonas.

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OPTIMALIZATION OF PHOTOREACTOR GEOMETRY FOR THE CULTIVATION OF CHLAMYDOMONAS REINHARDTII

Acta Polytechnica ◽

10.14311/ap.2018.58.0092 ◽

2018 ◽

Vol 58 (2) ◽

pp. 92

Author(s):

Roman Fekete ◽

Terézia Žáková ◽

Ľudmila Gabrišová ◽

Peter Kotora ◽

Peter Peciar ◽

...

Keyword(s):

Growth Rate ◽

Chlamydomonas Reinhardtii ◽

Biomass Yield ◽

Scale Up ◽

Model Organism ◽

Biomass Growth ◽

Hydrodynamic Conditions ◽

Optimal Conditions ◽

Optimal Ratio ◽

Kinetics Of

At the present time, a great attention is being paid to the use of algae. Algae can adapt to different conditions and can produce substances corresponding to responsible environments. The main problem in their cultivation is the design of a suitable photoreactor. It should create the optimal conditions for their growth, which is mainly dependent on the contact of the algae with the light. The intensity of the light depends on the hydrodynamic conditions in the photoreactor and on its geometry. This paper deals with the study of kinetics of growth and gross biomass yield of biomass in laboratory photobioreactors, respecting their geometrical similarity as a basis for a possible scale-up. An optimal ratio between biomass growth rate and its gross biomass yield as a function of the photoreactor geometry is searched. <em>Chlamydomonas reinhardtii</em> were used as the model organism.

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Kinetics of Electron Transfer between QA and QB in Wild Type and Herbicide-Resistant Mutants of Chlamydomonas reinhardtii

Zeitschrift für Naturforschung C ◽

10.1515/znc-1993-3-423 ◽

1993 ◽

Vol 48 (3-4) ◽

pp. 259-266 ◽

Cited By ~ 36

Author(s):

Antony R . Crofts ◽

Irene Baroli ◽

David Kramer ◽

Shinichi Taoka

Keyword(s):

Electron Transfer ◽

Chlamydomonas Reinhardtii ◽

Equilibrium Constants ◽

Wild Type ◽

Electron Transfer Kinetics ◽

Herbicide Resistant ◽

Mutant Strains ◽

High Fluorescence ◽

Kinetics Of ◽

Separate Measurement

Abstract We have investigated the electron transfer kinetics for reduction of plastoquinone by photo system II in six mutant strains of Chlamydomonas reinhardtii by following the decay of the high fluorescence state after flash activation, and compared the separate reactions of the two-electron gate with those of a wild type strain. By analysis of the electron transfer kinetics, and separate measurement of the equilibrium constant for stabilization of the bound semiquinone after one flash, we have been able to deconvolute the contributions of rate constants and equilibrium constants for plastoquinone binding and electron transfer to the overall process. Two mutations, S 264 A and A 251 V, led to a marked slowing of kinetics for reduction of plastoquinone to the bound semiquinone. In S 264 A , the second electron transfer was also slower, but was normal in A 251 V. In mutant G 256 D , the electron transfer kinetics were normal after the first flash, but slowed after the second. In mutants L 257 F , V 219 I, and F 255 Y , the electron transfer kinetics after both flashes were similar to those in wild type. We discuss the results in terms of a model which provides a description of the mechanism of the two-electron gate in terms of measured kinetic and equilibrium constants, and we give values for these parameters in all strains tested.

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