Genetic Engineering of Oxygen Affinity of Bacterial Hemoglobin: Effects on Hemoglobin Structure, Respiration, and Other Cellular Processes

[9910356] webster玻璃体振荡菌产生的血红蛋白表现出异常高的氧解离率。虽然VHb在其天然宿主中的功能尚不清楚，但有证据表明，它通过将氧气输送到末端氧化酶来促进缺氧条件下的呼吸。本研究将分析VHb突变体的生物物理特性和氧结合特性。从需氧细菌玻璃体振荡菌中获得的血红蛋白（VHb）的晶体结构为本研究提供了便利。这些研究将有助于评估每个位点导向突变是否发生了预测的结构变化，以及氧结合亲和力的变化如何改变微生物系统的呼吸活动和氧代谢。VHb在原生生物中的功能也将通过vgb（基因）敲除突变（消除VHb）来评估，以确定VHb在生长、呼吸和ATP合成中的作用，特别是在缺氧条件下。

9910356WebsterVitreoscilla produces hemoglobin that displays an unusually high rate of oxygen dissociation. Although the function of VHb in its natural host is not known, evidence suggests that it facilitates respiration under hypoxic conditions by funneling oxygen to the terminal oxidases. Biophysical characteristics and oxygen binding properties of selected mutants of VHb will be analyzed. The crystal structure of hemoglobin (VHb) obtained from the aerobic bacterium Vitreoscilla is available thus facilitating this research. These studies will help assess whether predicted structural changes from each of the site-directed mutations have occurred and how changes in the oxygen binding affinity alter respiratory activity and oxygen metabolism of microbial systems. VHb function in the native organism will be evaluated also using a vgb (gene) knockout mutation (to eliminate VHb) to determine the role of VHb on growth, respiration and ATP synthesis, especially under hypoxic conditions.