Travels in a world of small science*

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• 作者：Zelitch ; Israel
• 关键词：Robert H. Burris ; carbon dioxide assimilation ; catalase ; glycolate ; glyoxylate ; James G. Horsfall ; Severo Ochoa ; photorespiration
• 刊名：Photosynthesis Research
• 出版年：2001
• 出版时间：2001
• 年：2001
• 卷：67
• 期：3
• 页码：157-176
• 全文大小：564 KB

文摘

As a boy, I read Sinclair Lewis's Arrowsmith and dreamed of doing research of potential benefit to society. I describe the paths of my scientific career that followed. Several distinguished scientists served as my mentors and I present their profiles. Much of my career was in a small department at a small institution where independent researchers collaborated informally. I describe the unique method of carrying on research there. My curiosity about glycolate metabolism led to unraveling the enzymatic mechanism of the glycolate oxidase reaction and showing the importance of H$\_$2O$\_$2 as a byproduct. I discovered enzymes catalyzing the reduction of glyoxylate and hydroxypyruvate. I found α-hydroxysulfonates were useful competitive inhibitors of glycolate oxidase. In a moment of revelation, I realized that glycolate metabolism was an essential part of photorespiration, a process that lowers net photosynthesis in C$\_3$ plants. I added inhibitors of glycolate oxidase to leaves and showed: (1) glycolate was synthesized only in light as an early product of photosynthetic CO$\_$2 assimilation, (2) the rate of glycolate oxidation consumed a sizable fraction of net photosynthesis in C$\_3$ but not in C$\_4$ plants, and (3) that glycolate metabolism increased greatly at higher temperatures. For a while I studied the control of stomatal opening in leaves, and this led to the finding that potassium ions are a key solute in guard cells. I describe experiments that show that when photorespiration rates are high, as occurs at higher temperatures, genetically increasing leaf catalase activity reduces photorespiration and increases net photosythetic CO$\_$2 assimilation.