A gas-permeable photoacoustic cell

Fork, David C.; Herbert, Stephen K.

doi:10.1007/bf00033254

Cited by 20 publications

(9 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Photoacoustic measurements of energy storage were made in intact cells using a gas-coupled, continuouslymodulated photoacoustic spectrometer described previously Fork and Herbert 1991). Samples were prepared by filtering cells onto a disc of membrane filter (0.45 #m, Millipore), which was then loaded into the photoacoustic cell.…”

Section: Photoacoustic Measurementsmentioning

confidence: 99%

See 1 more Smart Citation

Light adaptation of cyclic electron transport through Photosystem I in the cyanobacterium Synechococcus sp. PCC 7942

1995

Self Cite

View full text Add to dashboard Cite

Photosystem I-driven cyclic electron transport was measured in intact cells of Synechococcus sp PCC 7942 grown under different light intensities using photoacoustic and spectroscopic methods. The light-saturated capacity for PS I cyclic electron transport increased relative to chlorophyll concentration, PS I concentration, and linear electron transport capacity as growth light intensity was raised. In cells grown under moderate to high light intensity, PS I cyclic electron transport was nearly insensitive to methyl viologen, indicating that the cyclic electron supply to PS I derived almost exclusively from a thylakoid dehydrogenase. In cells grown under low light intensity, PS I cyclic electron transport was partially inhibited by methyl viologen, indicating that part of the cyclic electron supply to PS I derived directly from ferredoxin. It is proposed that the increased PSI cyclic electron transport observed in cells grown under high light intensity is a response to chronic photoinhibition.

show abstract

Section: Photoacoustic Measurementsmentioning

confidence: 99%

“…The sample was supplied with 5% CO2 in air during energy storage versus irradiance measurements to avoid CO2 limitation. CO2 was supplied through a gas-permeable backing plate, as described elsewhere (Fork and Herbert 1991;Fork and Herbert 1993b). Analysis of photoacoustic data was made as described in Collier et al (1994).…”

Section: Photoacoustic Measurementsmentioning

confidence: 99%

Light adaptation of cyclic electron transport through Photosystem I in the cyanobacterium Synechococcus sp. PCC 7942

1995

Self Cite

View full text Add to dashboard Cite

show abstract

“…Photoacoustic measurements of energy storage were made using a continuously-modulated photoacoustic spectrometer described previously Fork and Herbert 1991). Samples were prepared by filtering cells onto a nitrocellulose disc (0.45 #m, Millipore), which was then loaded into a photoacoustic cell.…”

Section: Photoacoustic Measurements Of Energy Storagementioning

confidence: 99%

“…The sample was supplied with 5% CO2 in air during energy storage (ES) versus irradiance measurements to avoid CO2 limitation. CO2 was supplied through a gas permeable backing plate, as described elsewhere (Fork and Herbert 1991).…”

Section: Photoacoustic Measurements Of Energy Storagementioning

confidence: 99%

Changes in the cyanobacterial photosynthetic apparatus during acclimation to macronutrient deprivation

et al. 1994

Self Cite

View full text Add to dashboard Cite

When the cyanobacterium Synechococcus sp. Strain PCC 7942 is deprived of an essential macronutrient such as nitrogen, sulfur or phosphorus, cellular phycobiliprotein and chlorophyll contents decline. The level of β-carotene declines proportionately to chlorophyll, but the level of zeaxanthin increases relative to chlorophyll. In nitrogen- or sulfur-deprived cells there is a net degradation of phycobiliproteins. Otherwise, the declines in cellular pigmentation are due largely to the diluting effect of continued cell division after new pigment synthesis ceases and not to net pigment degradation. There was also a rapid decrease in O2 evolution when Synechococcus sp. Strain PCC 7942 was deprived of macronutrients. The rate of O2 evolution declined by more than 90% in nitrogen- or sulfur-deprived cells, and by approximately 40% in phosphorus-deprived cells. In addition, in all three cases the fluorescence emissions from Photosystem II and its antennae were reduced relative to that of Photosystem I and the remaining phycobilisomes. Furthermore, state transitions were not observed in cells deprived of sulfur or nitrogen and were greatly reduced in cells deprived of phosphorus. Photoacoustic measurements of the energy storage capacity of photosynthesis also showed that Photosystem II activity declined in nutrient-deprived cells. In contrast, energy storage by Photosystem I was unaffected, suggesting that Photosystem I-driven cyclic electron flow persisted in nutrient-deprived cells. These results indicate that in the modified photosynthetic apparatus of nutrient-deprived cells, a much larger fraction of the photosynthetic activity is driven by Photosystem I than in nutrient-replete cells.

show abstract

“…The PA cell used in this study was similar to one diagrammed elsewhere (Fork and Herbert 1991) except that the gas-permeable wall of the cell was replaced by a 2 mm thick Pyrex window. A double cascade thermoelectric plate (Melcor, Trenton, NJ) was appressed to the Pyrex window with thermal conducting grease.…”

Section: The Photoacoustic Systemmentioning

confidence: 99%

A photoacoustic method for rapid assessment of temperature effects on photosynthesis

2006

Self Cite

View full text Add to dashboard Cite

The photosynthetic and photoacoustic properties of leaf samples were studied using a photoacoustic system modified for precise temperature control. Data were collected over a temperature range of -10 degrees C to +60 degrees C. A distinct acoustic noise transient marked the freezing temperature of the samples. A positive absorption transient and a brief period of oxygen uptake marked the thermal denaturing temperature of the samples. Between these extremes, the effects of temperature on light absorption, oxygen evolution, and photochemical energy storage were quantified quickly and easily. Oxygen evolution could be measured as low as -5 degrees C and showed a broad temperature peak that was 10 degrees C lower under limiting light intensity than under saturating light intensity. Photochemical energy storage showed a narrower temperature peak that was only slightly lower for limiting light intensities than for saturating light intensities. In a survey of diverse plants, temperature response curves for oxygen evolution were determined readily for a variety of leaf types, including ferns and conifer needles. These results demonstrate that temperature-controlled photoacoustics can be useful for rapid assessment of temperature effects on photosynthesis and other leaf properties.

show abstract

A gas-permeable photoacoustic cell

Cited by 20 publications

References 6 publications

Light adaptation of cyclic electron transport through Photosystem I in the cyanobacterium Synechococcus sp. PCC 7942

Light adaptation of cyclic electron transport through Photosystem I in the cyanobacterium Synechococcus sp. PCC 7942

Changes in the cyanobacterial photosynthetic apparatus during acclimation to macronutrient deprivation

A photoacoustic method for rapid assessment of temperature effects on photosynthesis

Contact Info

Product

Resources

About