Substitutions of the conserved Thr42 increased the roles of the ε-subunit of maize CF1 as CF1 inhibitor and proton gate

Title:

Substitutions of the conserved Thr42 increased the roles of the ε-subunit of maize CF1 as CF1 inhibitor and proton gate

Creator:

Ni, Zhang-Lin, Wang, Da-Fu, and Wei, Jia-Mian

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:11e9c634-e93a-4105-b4c7-c52ca05623ac
uuid:11e9c634-e93a-4105-b4c7-c52ca05623ac
issn:0300-3604
doi:10.1023/A:1024387632311

Subject:

ATP synthase, circular dichroism, coupling factor 1, ε-subunit, photophosphorylation, and Zea mays

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

The conserved residue Thr42 of ε-subunit of the chloroplast ATP synthase of maize (Zea mays L.) was substituted with Cys, Arg, and Ile, respectively, through site-directed mutagenesis. The over-expressed and refolded ε-proteins were purified by chromatography on DEAE-cellulose and FPLC on mono-Q column, which were as biologically active (inhibiting Ca2+-ATPase activity and blocking proton gate) as the native ε subunit isolated from chloroplasts. The εT42C and εT42R showed higher inhibitory activities on the soluble CF1(-ε) Ca2+-ATPase than the εWT. The εT42I inhibited the Ca2+-ATPase activity of soluble CF1 and restored photophosphorylation activity of membrane-bound CF1 deficient in ε the most efficiently. Far-ultraviolet CD spectra showed that the portions of α-helix and β-sheet structures of the three mutants were somewhat different from εWT. Thus the conserved residue Thr42 may be important for maintaining the structure and function of the ε-subunit and the basic functions of the ε-subunit as far as an inhibitor of Ca2+-ATPase and the proton gate are related. and Zhang-Lin Ni, Da-Fu Wang, Jia-Mian Wei.

Language:

Multiple languages

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Coverage:

517-522

Source:

Photosynthetica | 2002 Volume:40 | Number:4

Harvested from:

CDK

Metadata only:

false