Molecular identification of Pseudozyma aphidis (Henninger & Windisch) Boekhout: first record from a Brazilian mangrove swamp

ABSTRACT (Molecular identification of Pseudozyma aphidis (Henninger & Windisch) Boekhout: first record from a Brazilian mangrove swamp). Pseudozyma aphidis (Henninger & Windisch) Boekhout is an anamorph yeast-like basidiomycete commonly found as saprotroph in vegetable debris, such as leaves and flowers. However, there are also reports that this species is pathogenic in humans, usually occurring in patients with some type of immunosuppression, which predisposes to opportunistic infections. Specimens of P. aphidis were collected from water samples and Rhizophora mangle L. leaves at different salinities along the Perequê River, located in a mangrove swamp area at Parque Estadual da Ilha do Cardoso, Cananéia municipality, São Paulo State, Brazil. Aliquots of these samples were spread in Petri dishes. The samples baited with cataphylls of Allium cepa L. were incubated for seven days at 21 ºC. After incubation, the baits were observed under microscope and the specimens were isolated and purified. The identification of the specimens was made through the phylogenetic analysis of the ITS rDNA region. This is the first record of P. aphidis in São Paulo State.

摘要（蚜虫假丝酵母（Pseudozyma aphidis (Henninger & Windisch) Boekhout）的分子鉴定：巴西红树林沼泽的首次记录）。蚜虫假丝酵母是一类类酵母型担子菌的无性型类群，通常以腐生方式存活于植物残体（如叶片、花朵）中。不过亦有研究报道该物种可引发人类致病感染，此类感染多发生于存在各类免疫抑制（immunosuppression）状况的患者，这类人群易于继发机会性感染（opportunistic infections）。
研究样本采自巴西圣保罗州卡内阿尼亚市卡多索岛州立公园（Parque Estadual da Ilha do Cardoso）红树林沼泽区域的佩雷凯河沿岸不同盐度梯度的水样及红海榄（Rhizophora mangle L.）叶片。将上述样本的等分试样涂布于培养皿（Petri dishes）中，以洋葱（Allium cepa L.）的鳞叶（cataphylls）为诱饵进行富集培养，于21℃条件下孵育7天。孵育结束后，在显微镜下观察诱饵样本，分离并纯化得到目标菌株。通过对核糖体DNA内转录间隔区（ITS rDNA）序列的系统发育分析（phylogenetic analysis）完成菌株标本的鉴定。本研究为圣保罗州境内首次记录到蚜虫假丝酵母的存在。