Lab. of Environmental Microbiology (LOEM) 

Prof. Jung and friends studing microbial ecology

Environmental Microbiology

We live in a world entirely covered by Microbes which have 5.0×1030 cells on our planet, and it is 108 greater than the number of stars in the observable universe. The microbes make up an unseen world, unseen at least by the naked eye. We explore this world, the creatures that inhabit it, and the things they do. So, we discover that processes carried out by microbes in the unseen world affect our visible world. These processes include virtually every chemical reaction in the biosphere that makes up the elemental cycles of carbon, nitrogen, and other elements necessary for life. The processes also involve interactions between organisms, both among microbes and between microbes and large organisms. And also, it interacts with climate changes.

 

We are studying Microbial Ecology because microbes mediate many processes essential to the operation of the biosphere. But there are other reasons for studying microbial ecology.


•      Microbes cause diseases of macroscopic organisms, including humans

•      Microbes help to make our food and other useful products

•      Microbes degrade and detoxify pollutants

•      Microbes are models for exploring principles in ecology and evolution

•      Microbes living today are models for early life on Earth and perhaps life on other planets

•      Microbes mediate biogeochemical processes that affect global climate

•      Microbes are everywhere, doing nearly everything

Our Research

The main interest of our research is the global material cycles, especially the Nitrogen cycle related to nitrification and denitrification. Nitrogen is essential for life, as it is a component of key biomolecules like nucleic acids and proteins. And it comprises the majority of Earth’s atmosphere, around 80%. Nitrification is a vital process of the global biogeochemical nitrogen cycle and plays a significant role in fertilizer loss in industrial agriculture, eutrophication, and the production of greenhouse gas N2O. On the other hand, nitrification is essential for efficient sewage treatment. Recently, major new nitrifiers, including ammonia-oxidizing bacteria (AOB), ammonia-oxidizing archaea (AOA), and complete nitrifiers (Comammox), were discovered, and it has made significant contributions to re-calculate the global nitrogen budget. Therefore, the nitrogen cycle study has become more complex and critical than before. Various ammonia oxidizers play a significant role in the environmental system, but their correct abundance with physiological mysteries still raises concerns.


Therefore, our research mainly focuses on analyzing physiological and genomic properties mediated by AOA, AOB, Comammox, and nitrite-oxidizing bacteria with the production of the greenhouse gas N2O and their kinetics by a multi-omics approach using microbial ecology, biogeochemistry, molecular biology, and bioinformatics. We are studying not only the N-cycle but also other essential processes of material cycles, such as Carbon, Surfer, and various metals.


Interdomainal relationship. 


Furthermore, we are hunting for microorganisms helpful for human life, such as Lactic Acid Bacteria (LAB) and Fermentation microbes from various environmental sources. The microbiome is the community of microorganisms (such as fungi, bacteria, and viruses) that exist in a particular environment. We are also studying microbial communication with hosts in the gut of life to determine the function of microbes. 

Ongoing Projects