• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Infection and immunity >Expression, cloning, and characterization of a Candida albicans gene, ALA1, that confers adherence properties upon Saccharomyces cerevisiae for extracellular matrix proteins.
【24h】

Expression, cloning, and characterization of a Candida albicans gene, ALA1, that confers adherence properties upon Saccharomyces cerevisiae for extracellular matrix proteins.

机译：白色念珠菌基因ALA1的表达，克隆和表征，赋予酿酒酵母细胞外基质蛋白依附性。

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Adherence of Candida albicans to host tissues is a necessary step for maintenance of its commensal status and is likely a necessary step in the pathogenesis of candidiasis. The extracellular matrix (ECM) proteins are some of the host tissue and plasma proteins to which C. albicans adheres through adhesins located on the fungal cell surface. To isolate genes encoding ECM adhesins, an assay was developed based on the ability of yeast cells to adhere to magnetic beads coated with the ECM protein fibronectin, type IV collagen, or laminin. A C. albicans genomic library was constructed by cloning XbaI-partially-digested and size-selected fragments into pAUR112, an Escherichia coli-yeast low-copy-number shuttle vector. The C. albicans library was transformed into Saccharomyces cerevisiae YPH 499, and clones capable of adherence were selected by using ECM protein-coated magnetic beads. A plasmid containing an approximately 8-kb insert was isolated from 29 adherent clones. These clones exhibited adherence to all ECM protein-coated magnetic beads and to human buccal epithelial cells. The ALA1 gene (for agglutinin-like adhesin) was localized by subcloning it into a 5-kb XbaI fragment which retained the adherence phenotype in both orientations. The complete DNA sequence of the 5-kb insert was determined, and an open reading frame (ORF) encoding 1,419 amino acid residues was identified. Deletions from the 5' and 3' ends extending into the DNA sequence encoding the 1,419-amino-acid ORF product inactivated the adherence phenotype, suggesting that it is the coding region of the ALA1 gene. A database search identified ALA1 to be similar to the C. albicans ALS1 (for agglutinin-like sequence 1) protein and the S. cerevisiae agglutinin protein (AG alpha1), although the homology at the primary amino acid sequence level is limited to the first half of each of these proteins. ALA1 contains a central domain of six tandem repeats of 36 amino acids. We discuss the significance of various predicted ALA1 structural motifs and their relationships to function in the adherence process.
机译：白色念珠菌对宿主组织的粘附是维持其共生状态的必要步骤，并且可能是念珠菌病发病机理中的必要步骤。细胞外基质（ECM）蛋白是白色念珠菌通过位于真菌细胞表面的粘附素粘附的某些宿主组织和血浆蛋白。为了分离编码ECM粘附素的基因，基于酵母细胞粘附涂有ECM蛋白纤连蛋白，IV型胶原蛋白或层粘连蛋白的磁珠的能力，开发了一种检测方法。通过将部分消化的XbaI片段和大小选择的片段克隆到大肠杆菌-酵母低拷贝数穿梭载体pAUR112中，构建了白色念珠菌基因组文库。将白色念珠菌文库转化为酿酒酵母YPH 499，并使用ECM蛋白包被的磁珠选择了能够粘附的克隆。从29个粘附克隆中分离出一个含有约8kb插入片段的质粒。这些克隆表现出对所有ECM蛋白包被的磁珠和人颊上皮细胞的粘附。通过将ALA1基因（用于凝集素样粘附素）亚克隆到一个5kb XbaI片段中，该片段在两个方向上均保持粘附表型。确定了5-kb插入物的完整DNA序列，并鉴定了编码1,419个氨基酸残基的开放阅读框（ORF）。从5'和3'末端的缺失延伸到编码1,419个氨基酸的ORF产物的DNA序列中，使粘附表型失活，表明它是ALA1基因的编码区。数据库搜索确定ALA1与白色念珠菌ALS1（针对凝集素样序列1）蛋白和酿酒酵母凝集素蛋白（AG alpha1）相似，尽管一级氨基酸序列水平的同源性仅限于第一个这些蛋白质各占一半。 ALA1包含一个由36个氨基酸组成的6个串联重复序列的中央结构域。我们讨论了各种预测的ALA1结构基序的重要性及其在粘附过程中的功能关系。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号