Carvalho Vívian Gonçalves, Terceti Mateus Souza, Dias Amanda Latercia Tranches, Paula Claudete Rodrigues, Lyon Juliana Pereira, de Siqueira Antônio Martins, Franco Marília Caixeta
Departamento de Ciências Biológicas, Universidade Federal de Alfenas, Alfenas, MG, Brazil.
Rev Inst Med Trop Sao Paulo. 2007 Jul-Aug;49(4):207-10. doi: 10.1590/s0036-46652007000400002.
Cryptococcus neoformans is an encapsulated yeast, etiological agent of cryptococcosis. The species is commonly associated with pigeon droppings and plant materials. The aim of the present work was to verify the presence of the yeast in pigeon droppings, and to identify the isolates obtained in serotypes and mating types (MAT). Ten samples of pigeon droppings were collected in the rural area of the city of Alfenas, Brazil. Samples were inoculated in agar Niger medium for fungal isolation and 22 isolates with characteristics of C. neoformans were obtained. The serotypes and MAT were determined by multiplex PCR using specific primers. Serotypes were also determined by using the Kit Crypto Check. Among the 22 samples evaluated, eight were identified as C. neoformans by classic identification tests. These samples were characterized as serotype A by the Kit Crypto check and as serotype A MAT alpha by the multiplex PCR. The present study reinforces the evidence that pigeon droppings are a reservoir for C. neoformans and confirms the prevalence of C. neoformans var. grubii (A alpha) among environmental isolates. It also demonstrates that multiplex PCR is an acceptable alternative for serotype analysis because it reduces the costs for each reaction and analyses serotype and MAT simultaneously.
新型隐球菌是一种有荚膜的酵母,是隐球菌病的病原体。该物种通常与鸽粪和植物材料有关。本研究的目的是验证鸽粪中该酵母的存在,并鉴定所获得分离株的血清型和交配型(MAT)。在巴西阿尔费纳斯市农村地区收集了10份鸽粪样本。将样本接种于尼日尔琼脂培养基中进行真菌分离,获得了22株具有新型隐球菌特征的分离株。使用特异性引物通过多重PCR确定血清型和MAT。血清型也通过使用Cryptotest试剂盒来确定。在评估的22个样本中,有八个通过经典鉴定试验被鉴定为新型隐球菌。这些样本通过Cryptotest试剂盒鉴定为A血清型,通过多重PCR鉴定为A血清型MATα。本研究进一步证明鸽粪是新型隐球菌的储存宿主,并证实了新型隐球菌变种格鲁比(Aα)在环境分离株中的流行情况。它还表明多重PCR是血清型分析的一种可接受的替代方法,因为它降低了每次反应的成本,并同时分析血清型和MAT。