Members of the C. neoformans/C. gattiii species complex are an important cause of serious humans infections, including meningoencephalitis. We describe here a 45 kDa extracellular cellulase purified from culture supernatants of C. neoformans var. neoformans. The N-terminal sequence obtained from the purified protein was used to isolate a clone containing the full-length coding sequence from a C. neoformans var. neoformans (strain B-3501A) cDNA library. Bioinformatics analysis indicated that this gene is present, with variable homology, in all sequenced genomes of the C. neoformans/C. gattii species complex. The cDNA clone was used to produce a recombinant 45 kDa protein in E. coli that displayed the ability to convert carboxymethyl cellulose and was therefore designated as NG-Case (standing for Neoformans Gattii Cellulase). To explore its potential use as a vaccine candidate, the recombinant protein was used to immunize mice and was found capable of inducing T helper type 1 responses and delayed-type hypersensitivity reactions, but not immune protection against a highly virulent C. neoformans var grubii strain. These data may be useful to better understand the mechanisms underlying the ability C. neoformans/C. gattii to colonize plant habitats and to interact with the human host during infection.

中文翻译：

---

隐球菌病原体分泌的免疫原性纤维素酶的表征

该成员隐球菌/ C. gattiii种复杂严重的人类感染，包括脑膜脑炎的一个重要原因。我们在这里描述了一种从新孢子虫变种的培养上清液中纯化的45 kDa细胞外纤维素酶。新形式。从纯化的蛋白质获得的N-末端序列被用于从新孢梭菌中分离出包含全长编码序列的克隆。新型隐球菌（菌株B-3501A）cDNA文库。生物信息学分析表明，该基因以可变的同源性存在于新隐梭菌/加迪梭菌的所有测序基因组中物种复杂。将cDNA克隆用于产生在重组45kDa的蛋白质的大肠杆菌所显示的能力转换羧甲基纤维素，因此被指定为NG-套（静置Ñ eoformans ģ attii Ç ellulase）。为了探索其作为候选疫苗的潜在用途，该重组蛋白被用于免疫小鼠，并被发现能够诱导1型T辅助反应和迟发型超敏反应，但不能抵抗针对高毒力的新变形梭菌var grubii株的免疫保护。。这些数据可能有助于更好地了解新孢梭菌/ C能力的潜在机制。加蒂 在植物栖息地定居并在感染过程中与人类宿主互动。