《生命科学》 2018, 30(3): 285-292
摘 要：摘 要：Sigma 因子分为两大类，分别为σ70 家族和σ54 家族。σ70 家族的基础sigma 因子，一般指导基因转录、应激反应、细胞发育以及辅助代谢，而σ54 家族参与细菌的氮和碳水化合物代谢、生物膜形成等。近年来研究发现，宿主体内的sigma 因子可通过调节基因表达来响应外界环境的改变、细胞发育信号以及指导生物代谢的合成；并且还发现原核生物有抗-sigma 因子和抗- 抗sigma 因子存在。一些微生物体内的sigma70因子能调控其抗生素、激素或某些代谢产物的产生，指导细胞耐酸、耐高渗或耐高温等胁迫条件，还能增强微生物的生长能力；sigma54 因子通常也能调节生物体代谢途径及氮源利用，参与生物固氮调控等。为了揭示sigma 因子在高效调控生物多功能方面的研究成果，现对sigma 因子及相关因子的结构特点、作用机制、生物多功能以及sigma 因子调控固氮功能等方面进行阐述。
Abstract: Abstract: Sigma factors are divided into two families: σ70 and σ54. The family σ70 generally guides the gene transcription， stress response， cell development and auxiliary metabolism. The family σ54 is involved in bacterial nitrogen and carbohydrate metabolism， biofilm formation. In recent years， the gene expression in response to the environmental changes， the cell development signal， and the synthesis of biological metabolism regulated by the sigma factors in the host have been found. Furthermore， there are anti-sigma and anti-anti sigma factors in prokaryotes. The sigma70 factor in some microbes regulates the production of antibiotics， hormones or metabolites， guides cells to respond to tolerate acid， hypertonic or high temperature stress conditions， and enhances the growth of microorganisms. The sigma54 factor can also regulate biological metabolic pathways and nitrogen source utilization， participate in biological nitrogen fixation regulation and so on. The mechanism， structure， bio-function， related factors of sigma factors and the regulation of nitrogen fixation by sigma factors will be elaborated in this review in order to reveal the research progress of sigma factors in the efficient regulation of bio-function.
