Modified reaction centers from Rhodobacter sphaeroides R26

FEBS Letters

Struck, A.¹  Scheer, H.¹ 

[1] Botanisches Institut der Universität, Menzinger Str. 67, D-8000 München 19, FRG

关键词: Photosynthesis;    Reaction center;    Pigment modification;    Pigment exchange;    Chlorophyll;    Bacteriochlorophyll a;    Bacteriochlorophyll a';    132-Hydroxy-bacteriochlorophyll a;    Chromatography;    Esterifying alcohol;    Epimerization;    Oxidation;    (Rhodobacter sphaeroides);    BChl;    bacteriochlorophyll;    BPhe;    bacteriopheophytin;    132-OH-BChl;    132-hydroxy-bacteriochlorophyll;    Rb.;    Rhodobacter;    Rp.;    Rhodopseudomonas;    Rs;    Rhodospirillum;   

DOI  :  10.1016/0014-5793(90)80598-D

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Incubation of photosynthetic reaction centers from Rhodobacter sphaeroides R26 with exogenous 13²-OH-bacteriochlorophyll a_p or a_GG according to Scheer et al. (1987) results in the exchange of endogenous bacteriochlorophyll a_p. The exchange amounts to ⩽ 50% according to HPLC analysis, corresponding to a complete replacement of the ‘monomeric’ bacteriochlorophylls, b_m and b_l, by exogenous pigment. The absorption spectra show small, but distinct changes in the Q_x-region of the bacteriochlorophylls, and bleaching of the modified reaction centers is retained. The corresponding binding sites must be accessible from the exterior, and allow for the introduction of a polar residue at C-13². This is supported by the observation of side reactions of the endogenous ‘monomeric’ bacteriochlorophylls within the reaction center pigments, e.g. epimerization and hydroxylation at C-13².

【 授权许可】

Unknown