A characteristic feature of C₄ plants is the differentiation of the photosynthetic leaf tissues into two distinct cell types: mesophyll (M) and bundle sheath (BS) cells. We have investigated several biochemical parameters, including pigment composition, polypeptide patterns, fluorescence at 77K, the activity of photosystems and ultrastructure of mesophyll and bundle sheath chloroplasts of maize (Zea mays L.) plants. It is shown that the BS chloroplasts have ~2-fold higher chlorophyll a/b ratio than M chloroplasts, 6.15 and 3.12 respectively. The PSI apoprotein (68 kDa) was more abundant in BS than in M thylakoids. Polypeptides belonging to PSII core antenna, are in similar amounts in both types of membranes, but the 45kDa band is more intensive in M thylakoids. Polypeptides in the region of 28–24 kDa of the light-harvesting complex of PSII (LHCII) are also present in both types of chloroplasts, though their amounts are reduced in BS thylakoids. The chlorophyll fluorescence emission spectra in M cells showed the presence of three bands at 686, 695 and 735 nm characteristics of LHCII, PSII core and PSI complexes, respectively. However, in the fluorescence spectrum of agranal plastids, there are almost traces of the band at 695 nm, which belongs to the PSII core complex. The research results revealed that the photochemical activity of PSII in BS chloroplasts is ~5 times less than in the chloroplasts of M cells. The highest PSI activity was found in maize BS chloroplasts.

C ₄植物的一个特征是光合叶组织分化为两种不同的细胞类型：叶肉（M）和束鞘（BS）细胞。我们已经调查了几个生化参数，包括颜料组合物，多肽的图案，荧光在77K，光系统的活性和叶肉的超微结构和玉米的维管束鞘叶绿体（玉蜀黍L.）的植物。结果表明BS叶绿体的叶绿素a / b高约2倍比M叶绿体的比例分别为6.15和3.12。BS中的PSI载脂蛋白（68 kDa）比M类囊体中的丰富。属于PSII核心天线的多肽在两种类型的膜中的含量均相似，但45kDa谱带在类固醇M类囊体中的强度更高。两种类型的叶绿体中也存在PSII光捕获复合物（LHCII）的28–24 kDa范围内的多肽，尽管在BS类囊体中它们的数量减少了。M细胞中的叶绿素荧光发射光谱表明，分别在LHCII，PSII核心和PSI配合物的686、695和735 nm处存在三个谱带。但是，在粒状质体的荧光光谱中，几乎在695 nm处有该条带的痕迹，该条带属于PSII核心复合物。研究结果表明，PSII在BS叶绿体中的光化学活性比M细胞的叶绿体中的光化学活性低约5倍。在玉米BS叶绿体中发现最高的PSI活性。