...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of bacteriology >A short-filament mutant of Anabaena sp. strain PCC 7120 that fragments in nitrogen-deficient medium.
【24h】

A short-filament mutant of Anabaena sp. strain PCC 7120 that fragments in nitrogen-deficient medium.

机译：鱼腥藻的短丝突变体。在缺氮培养基中破碎的PCC 7120菌株。

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

摘要

Strain 129 is a fragmentation mutant of the filamentous cyanobacterium Anabaena sp. strain PCC 7120. Growing with fixed nitrogen, this mutant forms filaments that are much shorter than wild-type filaments. Following starvation for fixed nitrogen, strain 129 becomes nearly unicellular and forms few heterocysts, although electron microscopy suggests that proheterocysts form while fragmentation occurs. Starvation for sulfate, phosphate, iron, and calcium does not cause this fragmentation. The affected gene in strain 129, fraC, was cloned by complementation and characterized. It encodes a unique 179-amino-acid protein rich in phenylalanine. Insertional inactivation of the chromosomal copy of fraC results in a phenotype identical to that of strain 129, while complementation using a truncated version of FraC results in only partial complementation of the original mutant. Heterocysts could be induced to form in N-replete cultures of strain 129, as in wild-type cells, by supplying extra copies of the hetR gene on a plasmid. Thus, FraC is required for the integrity of cell junctions in general but is apparently not directly involved in normal differentiation and nitrogen fixation.
机译：菌株129是丝状蓝细菌鱼腥藻属的片段断裂突变体。该突变体在固定氮下生长，形成的细丝比野生型细丝短得多。在缺乏固定氮的饥饿之后，菌株129几乎变成单细胞的，几乎没有形成异卵囊，尽管电子显微镜显示，原卵囊在形成碎片时形成。硫酸盐，磷酸盐，铁和钙的饥饿不会导致这种破碎。通过互补克隆并鉴定了菌株129中的受影响基因fraC。它编码富含苯丙氨酸的独特的179个氨基酸的蛋白质。 fraC的染色体拷贝的插入失活导致与菌株129相同的表型，而使用截短形式的FraC进行的互补只会导致原始突变体的部分互补。通过在质粒上提供额外的hetR基因拷贝，可以像在野生型细胞中一样，在N菌株129的完整培养物中诱导形成异质囊。因此，FraC通常是细胞连接完整性所必需的，但显然不直接参与正常分化和固氮。

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