Regulation of microbial sunscreen biosynthesis

知识价值。一些微生物，特别是蓝藻，已知可以合成次生代谢物，这些代谢物具有防晒功能，可以保护它们免受紫外线辐射（UV）的损害。在蓝藻细菌中，已经描述了两种主要类型的化合物：丝胞胺，一种独特的生物碱，具有有趣的生物学特性，以及类真菌菌素氨基酸（MAAs），一种源自氨基酸的小水溶性化合物。在过去的几年里，我们成功地开发了蓝藻菌株Nostoc punctiformme ATCC 29133，以研究这种防晒霜的遗传和分子基础。在过去几年中，这一研究领域取得了很大的进展。在这个项目中，我们将探索防晒生物学的各个方面，涉及基因功能与细胞区隔化的关联，以及它们的调节和进化。这项工作将在分子、生理和环境水平的组织中提供现有知识之间的联系，最终实现对微生物防晒霜的综合理解，并为其潜在应用奠定基础。更广泛的影响。当紫外线通量增加引起关注时，防晒霜是自然界中许多生物（从浮游生物到珊瑚）适应生态生理学的重要因素。微生物防晒霜之所以引起人们的兴趣，不仅是因为它们代表了一类新的次级代谢物，而且还因为它们在生物技术目的上的潜在适用性。此外，这项研究将代表一个非常有吸引力的机会，以普及正在进行的努力，以扩展到STEM未被充分代表的少数族裔K-12学生和亚利桑那州的普通公众，在那里，防止紫外线照射一直是一个问题，我们认为，微生物防晒霜可能会提供一个了解科学世界的诱惑。

Intellectual Merit. Some microorganisms, notably cyanobacteria, are known to synthesize secondary metabolites that serve a sunscreen function to protect them from damaging effects of exposure to ultraviolet radiation (UV). In cyanobacteria, two main types of such compounds have been described: scytonemin, a unique alkaloid of interesting biological properties, and mycosporine-like amino acids (MAAs), a family of small water-soluble compounds derived from amino acids. In the past few years we have successfully developed the cyanobacterial strain, Nostoc punctiforme ATCC 29133, to study the genetic and molecular basis of such sunscreens. Great strides have been made during the past few years in this field of research. In this project we will be probing aspects of sunscreen biology that relate to the association of gene function with cell compartmentalization, to their regulation and their evolution. This work will provide links between existing knowledge at the molecular, physiological and environmental levels of organization, eventually enabling an integrated understanding of microbial sunscreens and setting the basis for their potential application. Broader Impacts. Sunscreens are important factors in the ecological physiology of adaptation of many organisms in Nature, from plankton to corals at a time when increased UV-fluxes are of concern. Microbial sunscreens have attracted interest not only because they represent novel classes of secondary metabolites, but also because of their potential applicability for biotechnological purposes. Additionally, this research will represent a very attractive opportunity to populate ongoing efforts in outreach to STEM underrepresented minority K-12 students and the general public in Arizona, where protection from UV exposure is a constant concern, and where, we think, microbial sunscreens may offer an enticement to get to know the world of science.