TY  - JOUR
A1  - Vinothkumar, Kutti Ragunath
A1  - Raunser, Stefan
A1  - Jung, Heinrich
A1  - Kühlbrandt, Werner
T1  - Oligomeric structure of the carnitine transporter CaiT from Escherichia coli
T2  - Journal of biological chemistry
N2  - The carnitine transporter CaiT from Escherichia coli belongs to the betaine, choline, and carnitine transporter family of secondary transporters. It acts as an L-carnitine/gamma-butyrobetaine exchanger and is predicted to span the membrane 12 times. Unlike the other members of this transporter family, it does not require an ion gradient and does not respond to osmotic stress (Jung, H., Buchholz, M., Clausen, J., Nietschke, M., Revermann, A., Schmid, R., and Jung, K. (2002) J. Biol. Chem. 277, 39251-39258). The structure and oligomeric state of the protein was examined in detergent and in lipid bilayers. Blue native gel electrophoresis indicated that CaiT was a trimer in detergent solution. This result was further supported by gel filtration and cross-linking studies. Electron microscopy and single particle analysis of the protein showed a triangular structure of three masses or two parallel elongated densities. Reconstitution of CaiT into lipid bilayers yielded two-dimensional crystals that indicated that CaiT was a trimer in the membrane, similar to its homologue BetP. The implications of the trimeric structure on the function of CaiT are discussed.
Y1  - 2021
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/76263
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-762639
SN  - 0021-9258
VL  - 281.2006
IS  - 8
SP  - 4795
EP  - 4801
PB  - American Society for Biochemistry and Molecular Biology Publications
CY  - Bethesda, Md
ER  -