EAPSI: How Geomagnetic Field Strength Influences Magnetoreception and biodiversity within Magnetotactic Bacteria

趋磁细菌（MTB）是一种单细胞、对氧敏感的生物，它们能合成富含铁的磁小体颗粒。磁小体在形态上是不同的，反映了结核分枝杆菌独特的生态。因此，当磁小体被保存在地质记录中时，它们可以作为环境变化和微生物多样性的代用物，而环境变化和微生物多样性反过来又可能对气候敏感。该项目将测试MTB用于定位的磁场强度是否会调节它们的系统发育和磁小体的形成。因此，本次EAPSI将研究地磁场强度如何影响现代环境中的生物多样性和生物功能，从而提高磁小体作为缺氧环境和深时间微生物多样性代表的严密性。该研究人员将与中国科学院的潘永新博士合作。潘博士是结核分枝杆菌微生物学领域的全球领导者，获得他的设备和专业知识对这个项目的成功至关重要。磁化石（磁小体化石）有可能编码微生物多样性、环境条件和外部环境力之间的联系。EAPSI项目的目标是测试MTB中地磁场强度、系统发育和磁小体生物矿化之间是否存在可测量的关系。研究人员将测试地磁场的外力是否以及如何影响水生生态系统的生物多样性。此外，该项目将展示最小和最敏感的生物，微生物，如何随时间对地磁场的变化做出反应。PI将与中国科学院的潘永新博士合作，在规定的磁场强度下培养结核分枝杆菌的现场和实验室样本。然后，她将使用基因组分析，透射电子显微镜（TEM）和矿物磁性测量来表征这些生物体，以确定在可变磁场强度下培养的MTB在系统发育和磁小体生物矿化方面的差异（通过观察形貌，晶体结构，组成和磁小体的磁性粒度/域状态）。该奖项通过东亚和太平洋暑期学院项目颁发，支持一名美国研究生进行暑期研究；它是由国家科学基金和中国科技部共同资助的。

Magnetotactic bacteria (MTB) are single celled, oxygen-sensitive organisms that synthesize iron-rich particles called magnetosomes. Magnetosomes are morphologically distinct and reflect the unique ecology of MTB. Therefore, when magnetosomes are preserved in the geological record they can be used as proxies for environmental change and microbial diversity, that in turn may be sensitive to climate. This project will test if magnetic field strength, which MTB use for orientation, modulates their phylogeny and magnetosome formation. Thus, this EAPSI will investigate how geomagnetic field strength affects biodiversity and biological function in modern environments, thereby improving the rigor of magnetosomes as proxies for oxygen-poor environments and microbial diversity in deep time. The researcher will collaborate with Dr. Yongxin Pan at the Chinese Academy of Sciences, Beijing, China. Dr. Pan is a global leader in MTB microbiology and access to his facilities and expertise will be indispensable for the success of this project. Magnetofossils (fossilized magnetosomes) have the potential to encode linkages between microbial diversity, ambient environmental conditions, and external environmental forces. The goal of this EAPSI project is to test if there is a measurable relationship between the strength of the geomagnetic field, phylogeny, and magnetosome biomineralization in MTB. The researcher will test if and how the external force of the geomagnetic field affects biodiversity in aquatic ecosystems. Furthermore, this project will demonstrate how the smallest and most sensitive organisms, microbes, respond to changes in geomagnetic field throughout time. The PI will work with Dr. Yongxin Pan, at the Chinese Academy of Sciences in Beijing, China, to culture field and laboratory samples of MTB in prescribed magnetic field intensities. She will then characterize these organisms using genomic analyses, transmission electron microscopy (TEM), and mineral magnetic measurements to determine how MTB cultured in variable magnetic field strengths differ phylogenetically and in magnetosome biomineralization (by observing morphology, crystallographic structure, composition, and magnetic grain size/domain state of magnetosomes).This award is through the East Asia and Pacific Summer Institutes program and supports summer research by a U.S. graduate student; it is jointly funded by the National Science Foundation and the Chinese Ministry of Science and Technology.