The action of thermally activated tritium on the purple membrane and delipidated bacteriorhodopsin fragments has been studied, tritium incorporation into specified amino acid residues being quantified by Edman degradation. The membrane environment was found to affect the accessibility of amino acid residues for tritium. Bacteriorhodopsin fragments 14-31, 45-63, 81-89, 171-179, and 210-225 were localized to the membrane interior while fragments 4-12, 32-44, 64-65, 73-80, and 156-170 should lie outside or close to membrane surface. It was demonstrated that the peptide fragments joining transmembrane rods are not fully exposed to the solution.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1111/j.1432-1033.1988.tb14437.x | DOI Listing |
Biochim Biophys Acta Biomembr
June 2024
Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India. Electronic address:
Membrane protein folding is distinct from folding of soluble proteins. Conformational acquisition in major membrane protein subclasses can be delineated into insertion and folding processes. An exception to the "two stage" folding, later developed to "three stage" folding, is observed within the last two helices in bacteriorhodopsin (BR), a system that serves as a model membrane protein.
View Article and Find Full Text PDFBiophys Chem
October 2023
Chemistry Department, Willamette University, Salem, OR 97301, USA. Electronic address:
Recently in this Journal, James Lee employed his transmembrane electrostatically localized proton (TELP) hypothesis and the notion of a transient protonic capacitor to explain the force holding protons at the surface of bacteriorhodopsin purple membrane fragments. Here we show that purple membrane fragments cannot maintain the requisite transient non-zero transmembrane potential, and even if they could, it would not support the surface proton current moving from the P side to the N side that was reported by Heberle et al. (Nature, 1994).
View Article and Find Full Text PDFInt J Mol Sci
December 2021
School of Physics and Electronic Science, East China Normal University, 500 Dongchuan Road, Minhang District, Shanghai 200241, China.
Aromatic residues are highly conserved in microbial photoreceptors and play crucial roles in the dynamic regulation of receptor functions. However, little is known about the dynamic mechanism of the functional role of those highly conserved aromatic residues during the receptor photocycle. Tyrosine 185 (Y185) is a highly conserved aromatic residue within the retinal binding pocket of bacteriorhodopsin (bR).
View Article and Find Full Text PDFFEBS J
February 2022
Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan.
Specific antibody interactions with short peptides have made epitope tagging systems a vital tool employed in virtually all fields of biological research. Here, we present a novel epitope tagging system comprised of a monoclonal antibody named GD-26, which recognises the TD peptide (GTGATPADD) derived from Haloarcula marismortui bacteriorhodopsin I (HmBRI) D94N mutant. The crystal structure of the antigen-binding fragment (Fab) of GD-26 complexed with the TD peptide was determined to a resolution of 1.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
September 2020
Department of Chemical Sciences, Ariel University, 40700, Israel. Electronic address:
We report the first observation of an efficient, native membrane conjugation mechanism via positively charged, linear oligo-amines. Clustering of membrane fragments relies on electrostatic interactions between the net negative charge of the membranes and the positively charged, water-soluble mediators. This conjugation principle is demonstrated with two different bacterial membranes in which are embedded either the intrinsic membrane protein (MP) bacteriorhodopsin (bR) or the more recently identified xanthorhodopsin (XR).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!