Christopher G K, Sundermann C A
Department of Zoology and Wildlife, Auburn University, AL 36849, USA.
Biol Trace Elem Res. 1995 Dec;50(3):181-91. doi: 10.1007/BF02785409.
Stomatogenesis in ciliates is a complex and carefully orchestrated event. The exo- mutant SB255 of Tetrahymena thermophila has defects in mucocyst formation and docking and can also have one or two mouths. Three common culture media (proteose peptone, Medium 357, and yeast extract) were analyzed for total C, N, and inorganic elements and then tested for their effect on the number of mouths present in SB255. Cultures of SB255 grown in Medium 357 consisted of a mixed population of cells with either two mouths (doublet) or one mouth. Cultures from the same original stock grown in Medium 357 (SBm) and in 1% proteose peptone (SBpp) had different percentages of doublet cells in 1-, 2-, 3-, and 4-d-old cultures. When transferred to and grown in 1% yeast medium, both SBpp and SBm cultures had increased percentages of doublets over a 4-d culture period. When grown in 0.1, 0.5, or 1% yeast medium for 2 d, both SBpp and SBm cultures had more doublets in 1% than in either 0.1 or 0.5% yeast medium. Cultures of SBm grown in Medium 357 or 1% yeast medium for 2 d had a 10-fold increase in doublet cells compared to the inoculum. After 2 d in 1% proteose peptone, SBm cultures had percentages of doublet cells almost equal to that of the inoculum. Immunofluorescence and scanning electron microscopy (SEM) were used to examine cellular morphology of the doublet cells. These findings suggest that enriched media promote the growth of doublet cells. Furthermore, these doublets could prove to be a useful model system for the study of biological roles of trace elements.
纤毛虫的口器发生是一个复杂且精心编排的过程。嗜热四膜虫的外突变体SB255在黏液囊泡形成和对接方面存在缺陷，并且可能有一个或两个口器。分析了三种常用培养基（蛋白胨、357培养基和酵母提取物）中的总碳、氮和无机元素，然后测试它们对SB255中口器数量的影响。在357培养基中生长的SB255培养物由具有两个口器（双联体）或一个口器的细胞混合群体组成。来自同一原始菌株、分别在357培养基（SBm）和1%蛋白胨（SBpp）中生长的培养物，在1日龄、2日龄、3日龄和4日龄培养物中双联体细胞的百分比不同。当转移到1%酵母培养基中生长时，SBpp和SBm培养物在4天的培养期内双联体的百分比都增加了。当在0.1%、0.5%或1%酵母培养基中培养2天时，SBpp和SBm培养物在1%酵母培养基中的双联体都比在0.1%或0.5%酵母培养基中的更多。在357培养基或1%酵母培养基中培养2天的SBm培养物，其双联体细胞数量比接种物增加了10倍。在1%蛋白胨中培养2天后，SBm培养物中双联体细胞的百分比几乎与接种物相同。使用免疫荧光和扫描电子显微镜（SEM）检查双联体细胞的细胞形态。这些发现表明，富集培养基促进双联体细胞的生长。此外，这些双联体可能被证明是研究微量元素生物学作用的有用模型系统。
