MOLECULAR AND CELL BIOLOGY OF FUNGAL PATHOGENS

真菌病原体的分子和细胞生物学

• 批准号: 3091993
• 负责人: Ward E Bullock
• 金额: $ 69.35万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-01-01 至 1994-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3091993
• 关键词: Fungi; cell biology; communicable disease diagnosis; immunodeficiency; molecular pathology; pathologic process; recombinant proteins

In this program project we will conduct basic studies on medically important fungi at the molecular and cellular level to: 1) enhance understanding of fungal pathogenesis; 2) develop biochemical markers of infection by fungi; 3) explore human phagocyte surface receptor interactions with ligands of Histoplasma capsulatum (Hc) and the subsequent signaling of intraphagocyte biochemical events; 4) further characterize the gene structure and organization of Pneumocystis carinii which we and others recently demonstrated to be a member of the fungi by small subunit ribosomal RNA comparative analysis. Proj. 1 will produce and characterize nucleic acid probes to analyze the gene(s) and other cognate proteins responsible for encoding a plasma membrane proton ion pump in Hc yeasts that maintains a reasonably constant internal pH and may enhance survival within the acidic milieu of host macrophage phagolysosomes. Proj. 2 will examine the fate of Histoplasma yeasts and microconidia in human monocyte/macrophages and alveolar macrophages. The ligands within yeasts and conidia that are recognized by the LFA-1,CR3,p150,95 receptors of macrophages will be identified and purified. Mechanisms of signal transduction initiated by yeast binding to these receptors will be compared to those induced by binding of C3bi-coated erythrocytes to CR3. Proj. 3 will study the role of elastinolytic proteinase in the virulence of invasive Aspergillus species by isolating and cloning the gene for Aspergillus elastase (AE). Cloned AE gene will be used to produce recombinant AE for use in diagnostic testing and virulence studies; the chromosomal location of the gene will be determined, and AE gene probes will be evaluated for diagnosis by in situ hybridization. Proj. 4 will pursue observations that pathogenic species of Aspergillus and Cryptococcus produce large amounts of the polyol, D-mannitol. Capillary gas-chromatography will be used to determine if this metabolite can be employed as a quantitative, diagnostic marker of invasive infection by these fungi in experimental animals and patients. Proj. 5 will extend our knowledge of the fungal nature of P. carinii by employing cloned DNA fragments to characterize gene structure and organization. Genes encoding ribosomal RNAs and the calmodulin gene will be primary cloning targets. Clones of rRNA genes, chromosome markers and repetitive elements will be used as hybridization probes to examine genomic variation among isolates of P. carinii from rat and human hosts.

在这个项目中，我们将进行医学基础研究 重要的真菌在分子和细胞水平上：1）增强 了解真菌发病机制； 2) 开发生化标志物 真菌感染； 3）探索人类吞噬细胞表面受体 与荚膜组织胞浆菌 (Hc) 配体的相互作用以及随后的 吞噬细胞内生化事件的信号传导； 4）进一步表征 我们和其他人的卡氏肺孢子虫的基因结构和组织 最近通过小亚基证明是真菌的一员 核糖体RNA比较分析。 项目。 1 将产生并表征 用于分析基因和其他同源蛋白质的核酸探针 负责编码 Hc 酵母中的质膜质子离子泵 维持相当恒定的内部 pH 值并可以提高生存率 在宿主巨噬细胞吞噬溶酶体的酸性环境中。 项目。 2 会 检查人类组织胞浆菌和小分生孢子的命运 单核细胞/巨噬细胞和肺泡巨噬细胞。 酵母内的配体 和被 LFA-1、CR3、p150、95 受体识别的分生孢子 巨噬细胞将被识别和纯化。 信号机制 将比较由酵母与这些受体结合引发的转导 那些由 C3bi 包被的红细胞与 CR3 结合诱导的。 项目。 3 将研究弹性蛋白分解酶在毒力中的作用 通过分离和克隆基因来识别入侵曲霉属物种 曲霉弹性蛋白酶（AE）。 克隆的AE基因将用于生产 用于诊断测试和毒力研究的重组 AE；这 将确定基因的染色体位置，并进行AE基因探针 将通过原位杂交进行诊断评估。 项目。 4 会 进行曲霉属和隐球菌属致病菌的观察 产生大量的多元醇，D-甘露醇。 毛细管 气相色谱法将用于确定该代谢物是否可以 用作侵袭性感染的定量诊断标志物 这些真菌存在于实验动物和患者体内。 项目。 5 将延长我们的 通过使用克隆 DNA 了解 P. carinii 的真菌性质 片段来表征基因结构和组织。 基因编码 核糖体 RNA 和钙调蛋白基因将是主要克隆目标。 rRNA基因、染色体标记和重复元件的克隆将被 用作杂交探针来检查分离株之间的基因组变异 来自大鼠和人类宿主的 P. carinii。