糖交联放松促进了Helicobacter pylori的螺旋形状和胃殖民
Laura K Sycuro1, Zachary Pincus, Kimberley D Gutierrez
1Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, WA 98195, USA.
Cell
|June 1, 2010
概括
细菌螺旋状细胞形状,对于Helicobacter pylori来说至关重要
科学领域:
- 微生物学 微生物学
- 细胞生物学 细胞生物学
- 细菌病原体的产生
背景情况:
- 细菌螺旋状细胞形状的机制和功能意义尚未得到充分理解.
- 螺旋形态在Helicobacter pylori可能有助于其生存和复制在胃粘液层内.
- 酸甘油 (murein) sacculus通过交叉连接的甘油链,为细菌细胞提供结构完整性.
研究的目的:
- 为了确定参与生成Helicobacter pylori螺旋状细胞形状的基因.
- 阐明这些基因在细胞形态和胃殖民中的功能作用.
- 了解酸甘氨酸交叉连接对细菌形状决定的贡献.
主要方法:
- 基因查以识别变异细胞形状改变的突变者.
- 分析野生类型和突变菌株的二醇糖结构和交叉链接.
- 使用显微镜对细菌细胞形状进行定量形态分析.
主要成果:
- 四个基因 (csd1-3和ccmA) 被确定为螺旋细胞形成的重要基因.
- 缺少任何单一鉴定基因的突变者表现出曲的棒形状和增加的甘氨酸交联.
- 定量分析证实了每个蛋白质对形成形状的途径的独特贡献.
- 确定的途径是有效的胃殖民所必需的,独立于机动性.
结论:
- 多种蛋白质的协调作用,包括甘氨酸内酶和CcmA,调节甘氨酸的交叉链接.
- 这些蛋白质放松糖糖的交联,使螺旋细胞曲和扭曲成为可能.
- 这种形成形状的途径对于Helicobacter pylori在胃中定居至关重要.
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