綠膿桿菌訊息傳遞系統之反應調控者PA3346的純化方法及其和HptB作用的研究分析

The purification of response regulator PA3346 and its interaction with HptB in the two-component systems from PAO1

陳詩湄(Shih-May Chen)

指導教授 ： 張壽麟

國立清華大學/生命科學院/生物資訊與結構生物研究所/碩士(2009年)

摘要

Pseudomonas aeruginosa (PAO1) are Gram-negative bacteria and can survive in versatile habitats. The two-component systems (2CSs) help the bacteria to adapt changing environmental conditions. The 2CSs are responsible for regulating the synthesis of virulence factors, controling antibiotic susceptibility, the translocation of metabolites and ions, and biofilm formation. A 2CS often has a sensor histidine kinase and a response regulator. When bacteria detect stimulants in the environment, a series of signal transduction will be switched on. Protein members participate in the signal pathway including sensor, Hpt and response regulator proteins. In this study, we focus on the hybrid 2CS which exists in the PAO1. We cloned and purified the response regulator PA3346 proteins, and utlized the circular dichroism (CD) spectroscopy to estimate the secondary structure of the PA3346 protein. Furthermore, the isothermal titration calorimetry (ITC) experiment was performed to investigate the interaction between HptB and PA3346. Finally, the internet-based tool for structure modeling, SWISS-MODEL, was used to model the 3D structure of PA3346. Our results showed that the PA3346 is a protein with almostα-helix structure. Future experiments will be required to elucidate the detailed mode of interaction between PA3346 and HptB.

關鍵字

綠膿桿菌 ； 訊息傳遞

並列摘要

無資料

並列關鍵字

PA3346 ； two-component systems

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