Departamento de Microbiología y Proteómica, Instituto de Oftalmología "Fundación Conde de Valenciana", Mexico City, México.
Laboratorio de Microbiología Molecular, Universidad Autónoma de Querétaro, Santiago de Querétaro, México.
Mycoses. 2019 Jan;62(1):62-72. doi: 10.1111/myc.12849. Epub 2018 Oct 16.
In recent years, human keratitis caused by fungal plant pathogens has become more common. Biofilm is a structure that confers adaptations and virulence to fungi in keratitis. Neoscytalidium spp. are phytopathogenic and recently have been recognised as a human pathogen, using biofilm formation as a virulence factor.
The aim of this study was isolation, identification (at the species level) and characterisation of a new fungal keratitis agent.
PATIENTS/METHODS: The fungus was isolated from a 67-year-old male patient with a corneal ulcer. Biofilm formation and structure were evaluated by colorimetric methods and microscopy. To identify the fungus, morphological characteristics were examined and a phylogenetic analysis was performed.
We report the identification of a fungus, a member of the genus Neoscytalidium which is associated with human keratitis. Phylogenetic analysis and morphological observations on conidiogenous cells, which occur only in arthric chains in aerial mycelium and the coelomycetous synasexual morph is absent, identified a new species, Neoscytalidium oculus sp. nov. The fungus formed biofilm at a concentration of 1 × 10 conidia/mL, during 96 hours of incubation at 37°C, and also manifested haemolysis and melanin production. This is the first report in Latin America of a new species of Neoscytalidium from a clinical isolate has been identified.
近年来，由真菌植物病原体引起的人类角膜炎变得更为常见。生物膜是一种使真菌在角膜炎中获得适应和毒力的结构。枝孢属真菌是植物病原体，最近被认为是人类病原体，其生物膜形成是一种毒力因子。
本研究旨在分离、鉴定（种水平）并描述一种新的真菌性角膜炎病原体。
患者/方法：真菌从一名 67 岁男性角膜溃疡患者中分离得到。采用比色法和显微镜观察评估生物膜的形成和结构。为了鉴定真菌，我们检查了形态特征，并进行了系统发育分析。
我们报告了一种与人类角膜炎相关的枝孢属真菌的鉴定。基于分生孢子细胞的形态观察和系统发育分析，该真菌存在于仅在气生菌丝中形成的节孢子链中，不存在伞状分生孢子的有性型，鉴定为一个新种，即眼枝孢（Neoscytalidium oculus）。该真菌在 37°C 孵育 96 小时、浓度为 1×10 个分生孢子/mL 的条件下形成生物膜，同时还表现出溶血和黑色素产生。这是在拉丁美洲首次从临床分离株中鉴定出的一种新的枝孢属真菌。
