The 32 kDa tonoplast polypeptide Di associated with the V0‐type H+‐ATPase of Mesembryanthemum crystallinum L. in the CAM state: A proteolytically processed subunit B?

FEBS Letters

Lüttge, Ulrich²  Ratajczak, Rafael²  Zhigang, An¹  Löw, Rainer¹  Rausch, Thomas¹ 

[1] Botanisches Institut, Ruprecht-Karls-Universität, Im Neuenheimer Feld 360, D-69120 Heidelberg, Germany;Institut für Botanik, Technische Hoschschule Darmstadt, Schnittspahnstraβe 3-5, D-64287 Darmstadt, Germany

关键词: V-type H+-ATPase;    Tonoplast;    Crassulacean acid metabolism;    Protein turnover;    Subunit B;    Mesembryanthemum crystallinum L;    CAM;    crassulacean acid metabolism;    CHAPS;    (3-[3-cholamidopropyl)dimethylammonio]-1-propanesulfonate;    PAGE;    polyacrylamide gel electrophoresis;    PMSF;    phenylmethylsulfonyl fluoride;    SDS;    sodium dodecyl sulfate;   

DOI  :  10.1016/0014-5793(96)00556-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

In the facultative halophyte Mesembryanthemum crystallinum, the salt- or age-induced transition to crassulacean acid metabolism (CAM) leads to the occurrence of a tonoplast-bound 32 kDa polypeptide (D_i). The alignment of its N-terminal protein sequence with protein sequences of recently cloned higher plant V-ATPase B-subunits indicates that D_i may be derived from subunit B by proteolytic removal of a protein fragment of about 20 kDa from its N-terminus. Furthermore, an antiserum directed against D_i cross-reacts with subunit B from Nicotiana tabacum. It inhibits both proton pumping and ATP hydrolysis of the holoenzyme in M. crystallinum. As D_i remains firmly attached to the holoenzyme the proteolytic processing may have functional implications.

【 授权许可】

Unknown