Microbial Diversity and Extreme Environments

Research Background

The great majority of life on Earth is microscopic in size, and it is only visible through the microscope. Microbes are everywhere and they inhabit any environment, from very cold (below 0°C) to very hot (above 100°C) places, from very acidic to very alkaline sites, or high saline concentration, high pressure, or any other environment that might not look normal to humans. Microorganisms thriving under extreme conditions are the extremophiles.

This variable selection of systems is reflected by the huge diversity exiting in the microbial world. Currently, the level of microbial diversity on Earth is a topic of debate. While many microorganisms can easily be dispersed across the planet, the so called extreme environments present a selective factor for the living beings to develop in them. Thus, extreme environments can be considered as ideal model systems for studying ecological properties of microorganisms, their physiology, adaptative properties and many other characteristics related to microbial communities and specific microbial cells.

Due to the small size of microbes, working with them is not an easy task. Microscopic examination is required to see them. Classical microbiological studies required the ability to growth the microorganisms in the laboratory to be able to study their properties, such as growth conditions, nutrient sources, metabolic products, and so on. We now know that most microorganisms in the environment can not be brought into cultivation. So we have to design novel strategies to investigate their diversity, function, and potential applications. In order to understand our Planet, we are interested in the who, what, when, where, why and how questions about microbial life. The way to do it brings up an exciting experience to discover step by step the diverse microbial world.

It is too difficult (just to avoid to say impossible) to duplicate an organism’s host environment/ecosystem in a laboratory. However, some microbial processes or properties can be analyzed in the laboratory using isolated microorganisms. This apparent contradiction suggests a need for a variety of methodologies to be applied either in the laboratory or in the field.

With the advent of modern molecular techniques, we can understand the microbial environment in much greater detail. It is possible to use the information hold in the nucelic acids of microorganisms to detect those present in an environment. Thus, molecular methods based on DNA and RNA represent a very useful set of techniques to analyze microbial communities in situ. But nucleic acids can be used to both detect a microorganism and to look at its functional genes, and we can do similar research on microbial communities through metagenomic approaches. Of course, the amount of data to be processed increases exponentially with the number of different microorganisms in a sample and bioinformatic tools become an essential part of the research process. Detection of microorganisms and their functional genes are also complemented with an evaluation and analysis of the processes being carried out by those microbial communities in the environment.

Microorganisms are never alone. They work in communities, often composed by a large number of different types of cells. The study of microbial communities and their interaction with the environment are key aspects to understand the role and function of microorganisms in nature, and consequently the implications of microbial life at local and global scales in our planet.

Microorganisms thriving under extreme conditions generally present specific adaptations which allow them to develop in unique environments. The properties of their biomolecules are of interest in biotechnology due to their high stability which can be used in potential applications to industry or processes of commercial interest. The search for unique microorganisms and molecules also require the use of a variety of techniques.

Our group is keen in searching for novel methodologies and the application of a wide variety of strategies to answer specific questions. Methods involving a wide range of molecular techniques, the cultivation of microorganisms, biochemistry, physiology, ecology, biotechnology, genomics, bioinformatics, among others are some of the procedures commonly applied in our research. We pretend to further study microbial life from a multidisciplinary perspective and we will be glad to collaborate with other groups and individuals interested in related topics. For a list of our publications and projects, please, visit the corresponding page.