Origin and evolution of biomineralization and magnetotaxis
Microbes that synthesize minerals, a process known as microbial biomineralization, contributed substantially to the evolution of current planetary environments through numerous important geochemical processes. Despite its geological significance, the origin and evolution of microbial biomineralization remain poorly understood. Using a combination of molecular tools including genomics and metagenomics, we have investigated and characterized the magnetosome gene clusters (MGCs, a group of genes involved in magnetosome biomineralization and arrangement) from both cultivated and uncultivated magnetotactic bacteria (MTB). The results of my study will shed light on the origin and evolution of microbial biomineralization and magnetotaxis. Novel MGCs that identified by omics-based approaches will also be useful in generating new, synthetic magnetic nanoparticles.
Microbial control over global iron cycling
A number of microorganisms biomineralize intracellular or extracellular iron minerals and play essential roles in global biogeochemical cycling of iron. One of the most interesting examples of these types of organisms are the MTB, a widespread and polyphyletic group of prokaryotes that are able to uptake iron from environments and form intracellular nano-sized iron minerals of magnetite (Fe3O4) and/or greigite (Fe3S4), known as magnetosomes. We have investigated the diversity and biogeography of MTB communities from freshwater to saline habitats in diverse environments, and evaluated their roles in the present-day global iron cycling and the deposition of iron formation through the geological history.
Mechanisms of intracellular biomineralization in bacteria
Bacteria can sequester metals and other ions intracellularly in various forms ranging from poorly ordered deposits to well-ordered mineral crystals. The magnetosomes in MTB represent an ideal system for studying the mechanisms of intracellular biomineralization in bacteria. We have performed combined approaches of transmission electron microscopy, magnetic measurements and metagenomics to investigate the ultrastructure, biology and magnetosome formation of environmental MTB communities. These comprehensive analyses shed light on the biomineralization mechanisms and physiology of the poorly understood yet ecologically important MTB communities.
林巍，博士，研究员，中国科学院地质与地球物理研究所，主要从事地质微生物和微生物矿化研究。以趋磁微生物为主要研究对象，在生物趋磁性的起源和演化、古地磁场起源、微生物多样性和地理分布、微生物矿化的起源和机制等方面开展了较系统的研究。已发表学术论文40余篇，其中以第一作者在National Science Review、PNAS、The ISME Journal、Environmental Microbiology、Applied and Environmental Microbiology、Molecular Microbiology等知名刊物上发表论文20余篇，2篇第一作者论文被选为期刊封面文章；在施普林格 (Springer) 出版社出版英文专著一本；担任第一特邀主编在国际期刊Frontiers in Microbiology组织"Intracellular Biomineralization in Bacteria"主题专辑；并获得国家发明专利一项。现任国际SCI收录刊物Microbiological Research编委 (Editorial Board) 和 Frontiers in Microbiology的Guest Associate Editor，分别担任中国矿物岩石地球化学学会第九届环境矿物学专业委员会委员和中国微生物学会地质微生物学专业委员会委员。