Mares D, Fasulo M P
Institute of Botany, University of Ferrara, Italy.
Cytobios. 1990;61(245):89-95.
Protoanemonin (PrA) is an antimicrobial agent whose mechanism of action has not been clearly described. Some evidence exists which indicates that the compound inhibits growth by interacting with microtubules (MTs). In order to confirm this hypothesis, an ultrastructural study was undertaken in vitro on Epidermophyton floccosum and Trichophyton mentagrophytes, two dermatophytes which proved to be sensitive to the drug. A concentration of 1.25 x 10(-4) M (half-MIC dose) for 48 h, caused a series of ultrastructural alterations which were detected by scanning and transmission electron microscopy. Wave-like hyphae with distorted apical tips were frequently observed. Wall formation was variously affected as revealed by the deposition of incomplete septa and the accumulation of lomasome-like infoldings. An extrusion of extraparietal material binding adjacent filaments of the mycelia together was also produced. The nucleoplasm was characteristically crossed by MT-like structures. The possibility exists that PrA exerts its antifungal activity by MT interaction.
原白头翁素（PrA）是一种抗菌剂，其作用机制尚未明确描述。有证据表明该化合物通过与微管（MTs）相互作用来抑制生长。为了证实这一假设，对须发癣菌和须癣毛癣菌进行了体外超微结构研究，这两种皮肤癣菌对该药物敏感。1.25×10⁻⁴M的浓度（半数最小抑菌浓度剂量）作用48小时，引起了一系列超微结构改变，通过扫描电子显微镜和透射电子显微镜检测到。经常观察到顶端扭曲的波浪状菌丝。如不完全隔膜的沉积和类边体样褶皱的积累所示，细胞壁形成受到不同程度的影响。还产生了一种将相邻菌丝体细丝结合在一起的壁外物质挤出。核质中典型地出现了类似微管的结构。原白头翁素可能通过与微管相互作用发挥其抗真菌活性。
