Optical properties of the purpie bacterium reaction centres immobilized in polymer film

Title:

Optical properties of the purpie bacterium reaction centres immobilized in polymer film

Creator:

Frackowiak, D., Dudkowiak, A., Cegielski, R., Planner, A., and Schulz, C.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:35941222-9f0b-429f-a446-9687e0c94d1e
uuid:35941222-9f0b-429f-a446-9687e0c94d1e
urnnbn:urn:nbn:cz:aba007-000fnz

Subject:

absorption spectrum, bacteriochlorophyll, carotenoid-free mutant, delayed luminescence, fluorescence spectrum, isotropic and stretched films, linear dichroism, photoacoustic spectrum, polyvinyl alcohol film, and Rhodohacter sphaeroides

Type:

model:internalpart and TEXT

Format:

print

Description:

Reaction centres (RC) from the purpie bacterium Rhodohacter sphaeroides (strain R-24.1 and carotenoid-free mutant R-26.1) were separated and immobilized in isotropic and stretched polyvinyl alcohol (PVA) films. Absorption, fluorescence, delayed luminescence (8-300 K) and photoacoustic spectra (PAS) of immobilized samples were measured. The RC from wild strain R-24.1 and ffom carotenoid-free mutant R-26.1 were differently oriented in the stretched polymer film. In R-24.1 the long axis of the RC complex was directed under some angle with respect to the perpendicular direction to the PVA film plane, whereas in R-26.1 it was almost perpendicular to this plane. The shapes of linear dichroism (LD) of both strains were different. Delayed luminescence (DL) bands were located in a similar wavelength range as the bacteriochlorophyll and bacteriopheophytin prompt fluorescence bands. Intensity of DL was independent of temperature in the 8-300 K range. The intensity of DL was about three time lower than that of the fluorescence. The dependence of PAS on the frequency of radiation modulation and on the phase shift between modulated acting radiation and measured PAS showed that part of the thermal deactivation was undergoing slowly. Intensity ratio of the slow component to the fast one and/or decay time of the slow component of thermal deactivation were different for various chromophores and for RC ffom the two strains of bacteria.

Language:

Multiple languages

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Coverage:

283-299 and 125-141

Source:

Photosynthetica | 1995 Volume:31 | Number:2

Harvested from:

CDK

Metadata only:

false