Kammer G M, Pollack J D, Klainer A S
J Bacteriol. 1970 Oct;104(1):499-502. doi: 10.1128/jb.104.1.499-502.1970.
The morphology and the existence of a growth cycle of Mycoplasma pneumoniae have not been clearly established. There is disagreement as to whether this organism exists as a spherical or filamentous form, and whether it progresses from filamentous to spherical forms as the organism ages. A scanning-beam electron microscope (SEM) was utilized to provide detailed observations of the cycle of morphological changes during growth phases of M. pneumoniae. Cultures of cells grown and fixed in liquid suspension displayed morphological changes from spherical to filamentous and then to larger round forms. After 8 hr to 2 days of growth (phase I), spherical forms and aggregates were revealed. Two- to 6-day-old growth (phase II) was composed of both straight and branching filaments with bulbous elements situated at intervals along their lengths, and microcolonies composed predominantly of intertwined filaments. Six- to 10-day-old growth (phase III) was characterized by flattened, spherical organisms larger than those observed in phase I, occasional membranes or ghosts, and a paucity of aggregates or microcolonies. Thus, stereo-scan electron microscopic studies suggest that M. pneumoniae undergoes an orderly and sequential metamorphosis during its life cycle.
肺炎支原体的形态及其生长周期尚未明确确定。关于该生物体是以球形还是丝状形式存在，以及随着生物体老化它是否从丝状形式转变为球形形式，存在不同意见。利用扫描束电子显微镜（SEM）对肺炎支原体生长阶段的形态变化周期进行了详细观察。在液体悬浮液中生长并固定的细胞培养物显示出从球形到丝状，然后到更大圆形的形态变化。生长8小时至2天（阶段I）后，出现球形和聚集体。2至6天龄的生长（阶段II）由直的和分支的细丝组成，沿着细丝长度间隔分布着球状结构，以及主要由交织细丝组成的微菌落。6至10天龄的生长（阶段III）的特征是扁平的球形生物体，比阶段I中观察到的更大，偶尔有膜或空壳，并且聚集体或微菌落较少。因此，立体扫描电子显微镜研究表明，肺炎支原体在其生命周期中经历了有序且连续的变形。
