Site-directed cross-linking: establishing the dimeric structure of the aspartate receptor of bacterial chemotaxis
Cysteine residues introduced at specific locations in the aspartate receptor of Salmonella typhimurium provide anchor points for cross-linking and serve as chemical markers for structural studies of this oligomeric receptor. These markers have been used to measure the rate of subunit exchange between oligomeric receptors and to show that ligand binding inhibits this exchange. The cysteine-containing receptors can be oxidatively cross-linked to completion within the oligomeric receptor, indicating that the receptor has an even number of subunits. Based on this observation, a technique has been developed that can be used to determine the oligomeric structure of proteins under a variety of experimental conditions. The technique involves the measurement of the effect of dilution by cysteineless receptor subunits on cross-linking and reveals that the aspartate receptor is dimeric in detergent solution, in a mixed-micelle system, and in reconstituted membrane vesicles. Binding of aspartate does not change the oligomeric structure of the receptor, indicating that transmembrane signaling occurs within an oligomeric receptor of constant size.
- Research Organization:
- Univ. of California, Berkeley (USA)
- OSTI ID:
- 6838150
- Journal Information:
- J. Biol. Chem.; (United States), Vol. 263:13
- Country of Publication:
- United States
- Language:
- English
Similar Records
Transmembrane topology of the acetylcholine receptor examined in reconstituted vesicles
Structure, function, and evolution of bacterial ATP-binding cassette systems
Related Subjects
PROTEINS
BIOCHEMISTRY
RECEPTORS
CROSS-LINKING
ASPARTIC ACID
CYSTEINE
HEAVY WATER
OXYGEN 18
SALMONELLA TYPHIMURIUM
TRITIUM COMPOUNDS
AMINO ACIDS
BACTERIA
CARBOXYLIC ACIDS
CHEMICAL REACTIONS
CHEMISTRY
EVEN-EVEN NUCLEI
HYDROGEN COMPOUNDS
ISOTOPES
LABELLED COMPOUNDS
LIGHT NUCLEI
MEMBRANE PROTEINS
MICROORGANISMS
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXYGEN COMPOUNDS
OXYGEN ISOTOPES
POLYMERIZATION
SALMONELLA
STABLE ISOTOPES
THIOLS
WATER
550201* - Biochemistry- Tracer Techniques