Strategy for Increasing Yield in Aerobic Fermentations

当玻璃体杆菌的血红蛋白基因（vgb）存在于携带嗜热脂肪芽孢杆菌α -淀粉酶基因的重组大肠杆菌中时，该酶的产生受到刺激。该项目的主要目的是获得有关这种刺激机制的基本信息。vgb表达的产物，玻璃体震荡菌血红蛋白（VtHb）的作用将通过定点诱变来产生无活性和改变的蛋白质。然后将对这些无活性和改变的蛋白质进行测试，以观察刺激效果的变化。VtHb在缺氧条件下增加，可能在这些条件下通过促进呼吸发挥作用。其他计划中的实验包括将基本发现扩展到-淀粉酶以外的其他产品，以及其他细菌系统。

9309759 Webster When the hemoglobin gene (vgb) from the bacterium, Vitreoscilla, is present in recombinant E. coli carrying the gene for alpha- amylase from Bacillus stearothermophilus, the production of this enzyme is stimulated. The main objective of this project is to obtain basic information about the mechanism of this stimulation. The role of the product of vgb expression, Vitreoscilla hemoglobin (VtHb), will be examined using site-directed mutagenesis to produce inactive and altered proteins. These inactive and altered proteins will then be tested for a change in the stimulatory effect. VtHb increases under hypoxic conditions and presumably functions by facilitating respiration under these conditions. Other planned experiments include extending the basic findings to other products besides alpha-amylase, and to other bacterial systems.