Skip Navigation


Journal of Biochemistry Advance Access originally published online on December 11, 2006
Journal of Biochemistry 2007 141(1):85-91; doi:10.1093/jb/mvm010
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplementary data
Right arrow A corrigendum has been published
Right arrow A corrigendum has been published
Right arrow All Versions of this Article:
141/1/85    most recent
mvm010v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Request Permissions
Google Scholar
Right arrow Articles by Fujiki, T.
Right arrow Articles by Abea, K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Fujiki, T.
Right arrow Articles by Abea, K.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© 2006 The Japanese Biochemical Society.

Membrane Topology of Aspartate:Alanine Antiporter AspT from Comamonas testosteroni

Takashi Fujiki1, Kei Nanatani1, Kei Nishitani1, Kyoko Yagi1, Fumito Ohnishi1, Hiroshi Yoneyama2, Takafumi Uchida1, Tasuku Nakajima1 and Keietsu Abea1,*

1Laboratory of Enzymology; and 2Laboratory of Dairy Microbiology, Department of Molecular and Cell Biology, Graduate School of Agricultural Science, Tohoku University, Sendai, 981-8555 Japan

*To whom correspondence should be addressed. Tel: +81-22-717-8777, Fax: +81-22-717-8778, E-mail: kabe{at}biochem.tohoku.ac.jp

Received October 17, 2006; Accepted November 15, 2006


  Abstract

We cloned the aspT gene encoding the L-aspartate:L-alanine antiporter AspTCt in Comamonas testosteroni genomic DNA. Analysis of the nucleotide sequence revealed that C. testosteroni has an asp operon containing aspT upstream of the L-aspartate 4-decarboxylase gene, and that the gene order of the asp operon of C. testosteroni is the inverse of that of Tetragenococcus halophilus. We used proteoliposomes to confirm the transport processes of AspTCt. To elucidate the two-dimensional structure of AspTCt, we analysed its membrane topology by means of alkaline phosphatase (PhoA) and ß-lactamase (BlaM) fusion methods. The fusion analyses revealed that AspTCt has seven transmembrane segments (TMs), a large cytoplasmic loop containing ~200 amino acid residues between TM4 and TM5, a cytoplasmic N-terminus, and a periplasmic C-terminus. These results suggest that the orientation of the N-terminus of AspTCt differs from that of tetragenococcal AspT, even though these two AspT orthologues catalyse the same transport reactions.

Key Words: aspartate:alanine antiporter, bacteria, bioenergetics, fusion methods, membrane topology


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 J. Bacteriol.Home page
K. Nanatani, T. Fujiki, K. Kanou, M. Takeda-Shitaka, H. Umeyama, L. Ye, X. Wang, T. Nakajima, T. Uchida, P. C. Maloney, et al.
Topology of AspT, the Aspartate:Alanine Antiporter of Tetragenococcus halophilus, Determined by Site-Directed Fluorescence Labeling
J. Bacteriol., October 1, 2007; 189(19): 7089 - 7097.
[Abstract] [Full Text] [PDF]


Disclaimer:
Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.