綠膿桿菌磷酸根轉移系統之HptB變異體蛋白質結構研究與分析

Structural Studies of the C75A HptB Mutant in two Component System from Pseudomonas aeruginosa

林立婷(Li-Ting Lin)

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

The HptB protein studied in this thesis is a critical histidine phosphoryl transfer protein playing a role in the hybrid two-component system (TCS) in Pseudomonas aeruginosa. The primary signaling transduction pathway of TCS is through producing a continuous phosphorylation to activate the downstream response regulator protein which could regulate the expression of genes to adjust its antibiotic susceptibility, virulence, and formation of biofilm. In this study, the molecular structure of a stable mutant HptB:C75A was determined by X-ray crystallography at 1.65 Å resolution and also analyzed by NMR spectroscopy. The global structure of HptB:C75A was composed of five helices. Meanwhile, 1H–15N HSQC spectrum of HptB mutant are assigned near completion by using 3D hetero-nuclear NMR experiments. Comparison of HptB:C75A and other Hpt proteins on the electrostatic potential surfaces revealed difference around the conserved active site. The electrostatic potential surface around active site of HptB mutant is more positively charged than those of other Hpt proteins. This might explain the different specificity of Hpt module toward different response regulator. Further studies on the interaction of HptB and the response regulator will be performed by ITC and NMR technique.

關鍵字

綠膿桿菌 ； 磷酸傳遞 ； 結構

並列摘要

無資料

並列關鍵字

HptB ； structure

參考文獻

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