【摘要】 当蓝藻的囊状体膜在SDS与叶绿素之比为10:1的条件下增溶后,经不连续的SDS-聚丙烯酰胺凝胶电泳分离出六条含叶绿素的带。按照电泳迁移率增加的顺序,以及吸收光谱和荧光光谱的鉴定结果,自上而下分别命名为CP1a,CP1b,CP1c,CP1,CPa和FC。 CP1a,CP1b,CP1c和CP1四种复合体在蓝区和红区的吸收峰分别位于435 nm和675 nm处。该四种复合体在77°K的荧光发射峰位于726～728 nm。铁氰化钾-抗坏血酸氧化还原差异光谱证明这四种复合体都含有 P 700, 说明它们属于光系统Ⅰ反应中心复合体。低温荧光激发光谱表明这些复合体在625～626 nm,677 nm,690～692 nm和712～714 nm处有四个共同的荧光激发峰或肩。根据其E677/E714的比值,可将它们分为CP1a,CP1b和CP1c,CP1两种类型。它们之间的差异在于这两类复合体之间不同状态的色素比例明显不同。 第五种叶绿素蛋白复合体CPa在蓝区的吸收峰位于435nm处,在红区的吸收峰位于672nm处,CPa在77°K的荧光发射峰位于686 nm处,另外在690～696nm范围内还有一个较弱的肩。它属于光系统Ⅱ反应中心复合体。它仅存在于营养胞中。 异形胞中只有光系统Ⅰ反应中心复合体。更多还原

【Abstract】 When blue-green algae thylakoids are solubilized at a SDS: chl ratio of 10: 1,and subjected to discontinuous SDS-PAGE at 4℃, six chlorophyll zones are re-solved. The resolved zones in the order of increasing mobility are designatedCPia, CPlb, CPlc, CPl, CPa and FC.CPla, CPlb, CPlc and CPl have the same absorption maxima at 675 nmin the red region and 435 nm in the blue one. At 77°K, these four complexeshave the same fluorescence emission peak at 726-728 nm. The differentialspectra of potassium ferricyanide-oxidized against sodium ascorbatereducedsamples show that all the four complexes contain P 700, so they are consideredto belong to reaction center complexes of PS I. Low temperature excitation spe-ctra for the fluorescence emission at 726-728 nm show that all the four complexescontain four excitation peaks or shoulders at 625-626, 677, 690-692 and 712-714nm. According to their E 677/E 714 ratio, they are divided into two groups,i. e., CPla and CPlb as one, and CPlc and CPl as the other. The E 677/E 714 ratios in CPla and CPlb are higher than those in CPlc and CPl. Theexcitation ratios of these complexes may reflect the proportion of different statesof the chlorophyll in them.The fifth chlorophyll protein complex, CPa, has a red absorption maximumat 672 nm and a blue one at 435 nm. Its fluorescence emission peak at 77°K isat 686 nm, and in addition, a weak shoulder can be seen at 690-696 nm. It maywell be the reaction center complex of PS II, which can be found in vegetativecells only and seems to be completely absent from heterocyst cells.FC is a free chlorophyll band.更多还原