Direct effects of ionizing radiation on integral membrane proteins. Noncovalent energy transfer requires specific interpeptide interactions
Abstract
The 12 transmembrane alpha helices (TMHs) of human erythrocyte glucose transporter were individually cut by pepsin digestion as membrane-bound 2.5-3.5-kDa peptide fragments. Radiation-induced chemical degradation of these fragments showed an average target size of 34 kDa. This is 10-12 x larger than the average size of an individual TMH, demonstrating that a significant energy transfer occurs among these TMHs in the absence of covalent linkage. Heating this TMH preparation at 100{degree}C for 15 min reduced the target size to 5 kDa or less, suggesting that the noncovalent energy transfer requires specific helix-helix interactions. Purified phospholamban, a small (6-kDa) integral membrane protein containing a single TMH, formed a pentameric assembly in sodium dodecyl sulfate. The chemical degradation target size of this phospholamban pentamer was 5-6 kDa, illustrating that not all integral membrane protein assemblies permit intersubunit energy transfer. These findings together with other published observations suggest strongly that significant noncovalent energy transfer can occur within the tertiary and quaternary structure of membrane proteins and that as yet undefined proper molecular interactions are required for such covalent energy transfer. Our results with pepsin-digested glucose transporter also illustrate the importance of the interhelical interaction as a predominating force in maintaining the tertiary structuremore »
- Authors:
-
- Veterans Administration Medical Center, Buffalo, NY (USA)
- Publication Date:
- OSTI Identifier:
- 5733558
- Resource Type:
- Journal Article
- Journal Name:
- Journal of Biological Chemistry; (USA)
- Additional Journal Information:
- Journal Volume: 266:15; Journal ID: ISSN 0021-9258
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.; GLUCOSE; MEMBRANE TRANSPORT; MEMBRANE PROTEINS; CHEMICAL RADIATION EFFECTS; CELL MEMBRANES; ELECTROPHORESIS; ENERGY TRANSFER; HELICAL CONFIGURATION; MAN; PEPSIN; ACID PROTEINASES; ALDEHYDES; ANIMALS; CARBOHYDRATES; CELL CONSTITUENTS; CONFIGURATION; ENZYMES; HEXOSES; HYDROLASES; MAMMALS; MEMBRANES; MONOSACCHARIDES; ORGANIC COMPOUNDS; PEPTIDE HYDROLASES; PRIMATES; PROTEINS; RADIATION EFFECTS; SACCHARIDES; VERTEBRATES; 560120* - Radiation Effects on Biochemicals, Cells, & Tissue Culture
Citation Formats
Jhun, E, Jhun, B H, Jones, L R, and Jung, C Y. Direct effects of ionizing radiation on integral membrane proteins. Noncovalent energy transfer requires specific interpeptide interactions. United States: N. p., 1991.
Web.
Jhun, E, Jhun, B H, Jones, L R, & Jung, C Y. Direct effects of ionizing radiation on integral membrane proteins. Noncovalent energy transfer requires specific interpeptide interactions. United States.
Jhun, E, Jhun, B H, Jones, L R, and Jung, C Y. 1991.
"Direct effects of ionizing radiation on integral membrane proteins. Noncovalent energy transfer requires specific interpeptide interactions". United States.
@article{osti_5733558,
title = {Direct effects of ionizing radiation on integral membrane proteins. Noncovalent energy transfer requires specific interpeptide interactions},
author = {Jhun, E and Jhun, B H and Jones, L R and Jung, C Y},
abstractNote = {The 12 transmembrane alpha helices (TMHs) of human erythrocyte glucose transporter were individually cut by pepsin digestion as membrane-bound 2.5-3.5-kDa peptide fragments. Radiation-induced chemical degradation of these fragments showed an average target size of 34 kDa. This is 10-12 x larger than the average size of an individual TMH, demonstrating that a significant energy transfer occurs among these TMHs in the absence of covalent linkage. Heating this TMH preparation at 100{degree}C for 15 min reduced the target size to 5 kDa or less, suggesting that the noncovalent energy transfer requires specific helix-helix interactions. Purified phospholamban, a small (6-kDa) integral membrane protein containing a single TMH, formed a pentameric assembly in sodium dodecyl sulfate. The chemical degradation target size of this phospholamban pentamer was 5-6 kDa, illustrating that not all integral membrane protein assemblies permit intersubunit energy transfer. These findings together with other published observations suggest strongly that significant noncovalent energy transfer can occur within the tertiary and quaternary structure of membrane proteins and that as yet undefined proper molecular interactions are required for such covalent energy transfer. Our results with pepsin-digested glucose transporter also illustrate the importance of the interhelical interaction as a predominating force in maintaining the tertiary structure of a transmembrane protein.},
doi = {},
url = {https://www.osti.gov/biblio/5733558},
journal = {Journal of Biological Chemistry; (USA)},
issn = {0021-9258},
number = ,
volume = 266:15,
place = {United States},
year = {Sat May 25 00:00:00 EDT 1991},
month = {Sat May 25 00:00:00 EDT 1991}
}