F901318 (olorofim) is a novel antifungal drug that is highly active against species. Belonging to a new class of antifungals called the orotomides, F901318 targets dihydroorotate dehydrogenase (DHODH) in the pyrimidine biosynthesis pathway. In this study, the antifungal effects of F901318 against were investigated. Live cell imaging revealed that, at a concentration of 0.1 μg/ml, F901318 completely inhibited germination, but conidia continued to expand by isotropic growth for>120 h. When this low F901318 concentration was applied to germlings or vegetative hyphae, their elongation was completely inhibited within 10 h. Staining with the fluorescent viability dye bis-(1,3-dibutylbarbituric acid) trimethine oxonol (DiBAC) showed that prolonged exposure to F901318 (>24 h) led to vegetative hyphal swelling and a decrease in hyphal viability through cell lysis. The time-dependent killing of F901318 was further confirmed by measuring the fungal biomass and growth rate in liquid culture. The ability of hyphal growth to recover in drug-free medium after 24 h of exposure to F901318 was strongly impaired compared to that of the untreated control. A longer treatment of 48 h further improved the antifungal effect of F901318. Together, the results of this study indicate that F901318 initially has a fungistatic effect on isolates by inhibiting germination and growth, but prolonged exposure is fungicidal through hyphal swelling followed by cell lysis.

Infections caused by bacteria represent great motif of concern in health area. Therefore, there is a huge demand for more efficient antimicrobial agents. Antimicrobial polymers have attracted special attention as promising materials to prevent infectious diseases. In this study, a new polymeric system exhibiting antimicrobial activity against a range of Gram-positive and Gram-negative bacterial strains at micromolar concentrations (e.g., 0.8 µM) was developed. Controlled linear and star-shaped copolymers, comprising hydrophobic poly(butyl acrylate) (PBA) and cationic poly(3-acrylamidopropyl)trimethylammonium chloride) (PAMPTMA) segments, were obtained by SARA ATRP at 30 °C. The antibacterial activity of the polymers was studied by varying systematically the molecular weight, hydrophilic/hydrophobic balance and architecture. The molecular weight was found to exert the greatest influence on the antimicrobial activity of the polymers, with minimum inhibitory concentration values decreasing with increasing molecular weight. Live/dead membrane integrity assays and scanning electron microscopy analysis confirmed the bactericidal character of the synthesized PAMPTMA-(b)co-PBA polymers.

The growth and development of most fungi take place on a two-dimensional surface or within a three-dimensional matrix. The fungal sense of touch is therefore critical for fungi in the interpretation of their environment and often signals the switch to a new developmental state. Contact sensing, or thigmo-based responses, include thigmo differentiation, such as the induction of invasion structures by plant pathogens in response to topography; thigmonasty, where contact with a motile prey rapidly triggers its capture; and thigmotropism, where the direction of hyphal growth is guided by physical features in the environment. Like plants and some bacteria, fungi grow as walled cells. Despite the well-demonstrated importance of thigmo responses in numerous stages of fungal growth and development, it is not known how fungal cells sense contact through the relatively rigid structure of the cell wall. However, while sensing mechanisms at the molecular level are not entirely understood, the downstream signaling pathways that are activated by contact sensing are being elucidated. In the majority of cases, the response to contact is complemented by chemical cues and both are required, either sequentially or simultaneously, to elicit normal developmental responses. The importance of a sense of touch in the lifestyles and development of diverse fungi is highlighted in this review, and the candidate molecular mechanisms that may be involved in fungal contact sensing are discussed.

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