Stevenson I
Aust J Biol Sci. 1985;38(2):175-82.
Stages in the formation of protoplasts from S. coelicolor strain A3(2) have been studied by transmission electron microscopy. Protoplasts liberated from submerged mycelial growth were variable in size and were released when digestion of the cell wall by lysozyme had completely or almost completely taken place. Protoplasts did not fully adopt the typical rounded shape until after release. A single region of cytoplasm gave rise to more than one protoplast unit. Protoplasts released from spore germinants escaped from the tip of the germ tube, which was the region of the cell wall most susceptible to digestion. Protoplasts derived from spore germinants were more consistent in size and rounded up more rapidly. If a cross-wall had formed in a germinant then it gave rise to separate protoplasts from each cellular compartment. Protoplasts of either type contained a single DNA region. These studies give an indication of the cellular organization of a streptomycete colony, which can be visualized as a multinucleated assemblage of cellular units in a common cytoplasm. The assembly of units separates into a number of protoplasts on digestion of the cell wall.
通过透射电子显微镜研究了天蓝色链霉菌A3(2)菌株原生质体形成的各个阶段。从深层菌丝体生长中释放出的原生质体大小不一，当溶菌酶对细胞壁的消化完全或几乎完全发生时，原生质体就会被释放出来。原生质体在释放后才完全呈现出典型的圆形。单个细胞质区域可产生多个原生质体单位。从孢子萌发体释放出的原生质体从芽管顶端逸出，芽管顶端是细胞壁最易被消化的区域。源自孢子萌发体的原生质体在大小上更为一致，且更快地变圆。如果在萌发体中形成了横壁，那么它会从每个细胞区室产生单独的原生质体。这两种类型的原生质体都含有单个DNA区域。这些研究揭示了链霉菌菌落的细胞组织情况，可将其视为一个共同细胞质中细胞单位的多核集合体。在细胞壁消化时，单位集合体分离成许多原生质体。
