Spin Label Study of Apomembranes and Purple Membranes
نویسنده
چکیده
Tzvetana R. Lazarova and M aya Y. Velitchkova Central Laboratory of Biophysics, Bulgarian Academy of Sciences, Akad. G. Bonchev Str., bl. 21, Sofia 1113, Bulgaria Z. Naturforsch. 48c, 500-503 (1993); received July 3/September 16, 1992 Purple Membranes, Apomembranes, Retinal, Membrane Fluidity, Spin Label Three spin-labelled fatty acids were used to detect the dynamics of lipid bilayer of apomem branes and purple membranes. It was found that ESR spectra of spin labels bound to apo membranes showed a temperature-induced changes rather similar to those seen with purple membranes. At the same time, however, the values of hyperfine splitting parameter 2Tm were lower as compared to purple membranes. The results pointed out that the removal of the retinal from purple membranes affects the dynamics of lipid bilayer and apomembranes were more rigid structure than those of purple membranes.
منابع مشابه
Isolation of Photochrome Transmembrane Protein Bacteriorhodopsin from Purple Membranes of Halobacterium Halobacterium Halobium. New Method for Isolation
This paper presents improved method for isolation of photochrome transmembraine protein bacteriorhodopsin (output 5 mg from 100 g of wet biomass) capable to transform light energy to electrochemical energy of generated protons H + and АТP. The protein was isolated from purple membranes of photo-organotrophic halobacterium Halobacterium halobium by cellular autolysis by distilled water, processi...
متن کاملEvidence for Buried Carboxyl Residues and Immobilization
Chemical modification and electron spin resonance techniques were used to study the topography of carboxyl residues in purple membranes. The results showed that buried carboxyl groups are )ocated in hydrophobic protein domains at least 16 A from the membrane surface, and that the carboxyl-terminal tail is partially immobilized. Carboxyl groups on bacteriorhodopsin in purple membranes...
متن کاملSpin-Labeled Membranes
In the next few minutes I shall present a very brief discussion of what the spin-label technique is, and how it may be used to study biological membranes, x, 2 A "spin label" is a synthetic organic paramagnetic free radical. Most spin
متن کاملLight-Controlled Spin Filtering in Bacteriorhodopsin
The role of the electron spin in chemistry and biology has received much attention recently owing to to the possible electromagnetic field effects on living organisms and the prospect of using molecules in the emerging field of spintronics. Recently the chiral-induced spin selectivity effect was observed by electron transmission through organic molecules. In the present study, we demonstrated t...
متن کاملThe Influence of Spin Label on the Transport of Ascorbate across Artificial Membranes
Spin label 1,14 studies on DPPC membranes revealed an increased rigidity of the membrane with increasing spin label concentrations. This causes a retardation in permea tion rate of Na-ascorbate. At temperatures > 40 °C, that is above the phase transition temperature, the ESR spectrum of a spin labelled DPPC membrane is very similar to a free spin label spectrum and yet the permeation rate of N...
متن کامل