嗜酸硫杆菌双组分信号转导系统多样性分析

为探索嗜酸硫杆菌(Acidithiobacillus)对极端矿山环境条件感知和反应分子机制的差异,利用生物信息学方法鉴定和分析了两株嗜酸氧化亚铁硫杆菌、一株喜温嗜酸硫杆菌和一株耐冷嗜酸硫杆菌的双组分信号转导系统(TCS)结构多样性特征.结果表明,4株嗜酸硫杆菌拥有27~38个TCS蛋白,聚类分析显示有16组配对的TCS族、4组孤儿组氨酸蛋白激酶(HK)和9组孤儿反应调节蛋白(RR),与其进化分支有较好的相关性;其中9个配对和5个不配对的TCS 蛋白族为嗜酸硫杆菌菌株所共有,其余特有TCS均在一个或几个菌株中缺失.嗜酸硫杆菌菌株共有的TCS功能涉及氮素固定及代谢调节、柠檬酸/苹果酸代谢调节等,特有TCS功能涉及如趋化性调控、重金属响应、铜抗性调控等,这可能有助于菌株在极端矿山环境中生存.

Diversity analysis of two-component signal transduction systems in the genusAcidithiobacillus

To investigate the difference in the molecular mechanism of the genus Acidithiobacillus responding to extreme mine environment, two A. ferrooxidans strains, one A. caldus strain and one A. ferrivorans strain were analyzed in the diversity of two-component signal transduction systems (TCS) by using the bioinformatics method. The results showed that 27~38 TCS proteins were respectively identified from the four Acidithiobacillus strains. These TCS proteins were clustered into 16 paired groups, four groups of orphan histidine protein kinases, and nine groups of orphan response regulator proteins, demonstrating significant correlationship with their evolutionary branches. Among TCS proteins, nine groups of paired TCSs and five groups of non-paired TCSs were shared by the four strains of Acidithiobacillus, while the other TCSs were absent at least in one strain. Common TCS proteins of the four strains played basic biological roles including nitrogen fixation and citrate/malate metabolism regulation. Specific TCS proteins got involved in chemotaxis regulation, heavy metal response, and copper resistance regulation, which might contribute to survival of bacterial strains under the extreme mine environment.