Bioluminescence: Molecular Mechanisms and Biochemical Control in Microorganisms

生物发光：微生物的分子机制和生化控制

• 批准号: 9306879
• 负责人: John Hastings
• 金额: $ 20.4万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-07-15 至 1996-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9306879&HistoricalAwards=false
• 关键词: Bioluminescence; Molecular; Mechanisms; Biochemical; Control

The objective of this research is to understand the molecular and biochemical mechanisms of bioluminescence in bacteria and dinoflagellates, including the genes coding for the proteins involved and their evolutionary origins. In dinoflagellates, the luciferin, a tetrapyrrole probably derived from chlorophyll, is oxidized enzymatically to produce light. The mechanism of this reaction, the enzymatic intermediates, and the identity of the emitter, will be studied using proteins produced by recombinant techniques from cloned genes and synthetic substrate(s). The structures, sequences and organization of these genes will be determined, and their evolutionary origins will be investigated. In bacteria, luciferase is a flavoprotein monooxygenase which catalyzes the oxidation of aliphatic aldehydes to the corresponding acids. Luciferase-bound intermediates along with accessory "emitter" proteins will be characterized using photophysical and enzymological techniques to investigate the nature of the primary excited state and how it is formed. Possible alternative functions of luciferase, such as protection against cellular damage by oxygen radicals, will also be studied using bacteria which grow in 100% oxygen and were isolated from a human wound. %%% Although the emission of visible light by living organisms is a rare, curiosity of nature, it is also a unique tool for exploring unusual biological energetic processes. The objective of the research is to understand the molecular and biochemical mechanisms of bioluminescence, and to examine the control and evolutionary origin of the genes involved. We will principally use simple marine unicellular organisms in this study; bacteria and dinoflagellates. The bacteria emit blue-green light. These cells often live in association with higher organisms in the gut tract or in specialized light emitting organs. Dinoflagellates have a very different bioluminescence system which seems to have evolved independently, and makes use of a substance related to chlorophyll. The dinoflagellates are responsible for the blooms (called red tides) in the ocean, where they produce potent neurotoxins which accumulate in the shellfish that ingest them, thus making the shellfish poisonous for man. The phosphorescence of the ocean seen at night is also due to dinoflagellate bioluminescence. Our studies are learn about the biochemistry for this peculiar light emission reaction.

这项研究的目的是了解细菌和甲藻生物发光的分子和生化机制，包括编码相关蛋白质的基因及其进化起源。 在甲藻中，荧光素（一种可能源自叶绿素的四吡咯）被酶氧化以产生光。 将使用通过重组技术从克隆基因和合成底物产生的蛋白质来研究该反应的机制、酶促中间体以及发射器的身份。 这些基因的结构、序列和组织将被确定，并研究它们的进化起源。 在细菌中，荧光素酶是一种黄素蛋白单加氧酶，可催化脂肪醛氧化成相应的酸。 将使用光物理和酶学技术来表征荧光素酶结合的中间体以及辅助“发射体”蛋白，以研究初级激发态的性质及其形成方式。 荧光素酶可能的替代功能，例如防止氧自由基造成的细胞损伤，也将使用在 100% 氧气中生长并从人体伤口中分离出来的细菌进行研究。 %%% 虽然生物体发射可见光是一种罕见的、大自然的好奇心，但它也是探索不寻常的生物能量过程的独特工具。 该研究的目的是了解生物发光的分子和生化机制，并检查相关基因的控制和进化起源。 在这项研究中，我们将主要使用简单的海洋单细胞生物；细菌和甲藻。 细菌发出蓝绿光。这些细胞通常与肠道或专门的发光器官中的高等生物一起生活。 甲藻具有非常不同的生物发光系统，该系统似乎是独立进化的，并利用与叶绿素相关的物质。 甲藻是海洋中藻华（称为赤潮）的罪魁祸首，它们产生强效神经毒素，这些毒素在摄入它们的贝类中积累，从而使贝类对人类有毒。 夜间看到的海洋磷光也是由于甲藻生物发光所致。 我们的研究是了解这种特殊的发光反应的生物化学。