Villar L A, Salazar M E, Restrepo A
Laboratorio de Micología, Corporación para Investigaciones Biológicas Hospital Pablo Tobón Uribe, Medellin, Colombia.
J Med Vet Mycol. 1988;26(5):269-76. doi: 10.1080/02681218880000381.
Incubation of Paracoccidioides brasiliensis conidia at 20-25 degrees C (RT) results in two types of colonies, mycelial (M) and yeast (YRT). A study of the latter colonies was undertaken. Conidia were plated in complex (BHI) and chemically-defined media (CDCM), with and without fetal calf serum (FCS). Incubation was carried out at 21 degrees C for 4 weeks. The mean number of YRT colonies was approximately 18.5% on BHI agar. Selected YRT colonies were transferred to liquid CDCM, incubated 7 days at 21 degrees C and transferred to solid media; YRT appearance was preserved in 95% of the colonies if media were FCS-supplemented; otherwise, most colonies reverted to the M form. When FCS was replaced by bovine albumin or by alpha-globulin, 63% and 68% respectively of the colonies obtained after plating YRT cells, became mycelial. Comparative morphologic studies of both YRT and yeasts grown at 37 degrees C suggested that there were no major differences between these two types of yeast cells when size and budding were taken into consideration. The results indicate that in this particular variant, dimorphism is not exclusively temperature-dependent.
将巴西副球孢子菌分生孢子在20 - 25摄氏度（室温）下培养会产生两种类型的菌落，即菌丝体（M）和酵母型（YRT）。对后一种菌落进行了研究。将分生孢子接种在复杂培养基（脑心浸液培养基，BHI）和化学成分明确的培养基（CDCM）中，添加或不添加胎牛血清（FCS）。在21摄氏度下培养4周。在BHI琼脂上，YRT菌落的平均数量约为18.5%。选择的YRT菌落转移至液体CDCM中，在21摄氏度下培养7天，然后转移至固体培养基；如果培养基添加了FCS，95%的菌落能保持YRT形态；否则，大多数菌落会变回M型。当用牛白蛋白或α球蛋白替代FCS时，接种YRT细胞后获得的菌落分别有63%和68%变成了菌丝体。对在37摄氏度下生长的YRT和酵母进行的比较形态学研究表明，考虑到大小和出芽情况，这两种酵母细胞之间没有重大差异。结果表明，在这个特定变体中，双态性并非完全依赖于温度。
